A Dissertation
entitled
One Man’s Threat is Another Man’s Challenge: Applying the Biopsychosocial Model of Threat and Challenge to a Placebo Paradigm by
Fawn C. Caplandies
Submitted to the Graduate Faculty as partial fulfillment of the requirements for the
Doctor of Philosophy Degree in
Experimental Psychology
______Dr. Andrew L. Geers, Committee Chair
______Dr. Jason Rose, Committee Member
______Dr. Jason Levine, Committee Member
______Dr. Mathew Tull, Committee Member
______Dr. Patricia Case, Committee Member
______Dr. Amanda Bryant-Friedrich, Dean College of Graduate Studies
The University of Toledo
July 2018
Copyright 2018, Fawn C. Caplandies
This document is copyrighted material. Under copyright law, no parts of this document may be reproduced without the expressed permission of the author. An Abstract of
One Man’s Threat is Another Man’s Challenge: Applying the Biopsychosocial Model of Threat and Challenge to a Placebo Paradigm
by
Fawn C. Caplandies
Submitted to the Graduate Faculty as partial fulfillment of the requirements for the Doctor of Philosophy Degree in Experimental Psychology
The University of Toledo August 2018
The Biopsychosocial Model of Threat and Challenge (BPS; Blascovich & Tomaka, 1996) informs research on stress and coping. The present research proposes a new application of this conceptual model: To explain occurrences of placebo and nocebo effects. It is argued here that the processes outlined in the BPS model, concerning how people cope and respond to stress, can be employed to explain how placebo and nocebo effects arise in some cases. Following a review of the BPS model and the placebo effect literature, a pilot experiment is described. In this pilot research, distinct physiological changes, in line with the predictions of the BPS model for coping with stress are exhibited among participants receiving positive placebo expectations about a treatment, compared to controls. That is, treatment expectation participants displayed greater physiological resilience to stress when they were informed they had a new resource (e.g., the treatment expectation) to deal with a situation in which the actual resources available did not change. The main experiment builds on this pilot work. In this experiment, both perceptions of resources and demands were manipulated. This experiment was designed to extend beyond the Pilot Study to demonstrate evidence for a BPS explanation of
iii placebo effects and nocebo effects in the same paradigm. Results depicted that task engagement did not significantly differ from baseline through the performance task. In addition, participant’s completion of the performance task did not lead to significant differences between conditions. Within the BPS Model, participants provided with a resource and demand manipulation did not significantly demonstrate physiological indicators of challenge or threat. Implications and explanations of these findings, as well as directions for future research are discussed.
Keywords: placebo, nocebo, threat, challenge, stress, coping, biopsychosocial model
iv
This dissertation is dedicated to my parents, Tom & Yvonne Caplandies, for unrelenting
support, guidance, endless draft reading, and always reminding me not to worry during
major milestones because “cannibalism is against the law…”
v Table of Contents
Abstract ...... iii
Table of Contents ...... vi
List of Tables ...... xi
List of Figures ...... xii
List of Abbreviations ...... xiii
1 Introduction ...... 1
1.1 Project Overview ...... 1
1.2 Stress and Coping Theory ...... 1
1.3 Connecting the Stress and Coping Theory to the Biopsychosocial Model ...... 4
1.4 Biopsychosocial Model of Threat and Challenge ...... 6
1.4.1 Task Engagement ...... 6
1.4.2 Resources and Situational Demands ...... 7
1.4.3 Threat and Challenge ...... 8
1.4.4 Biopsychosocial Model Measurement ...... 9
1.4.5 Domains of Biopsychosocial Model Application ...... 11
1.4.6 Biopsychosocial Model and Placebo Effects ...... 13
1.5 Placebo Effects...... 14
1.5.1 Placebo Treatment Expectation Manipulation of Resources ...... 18
1.6 Nocebo Effects ...... 19
1.6.1 Nocebo Treatment Expectation Manipulation of Situational
Demand ...... 20
1.7 Simultaneous Manipulation of Resources and Demands ...... 21
vi 1.8 Aim of Placebo, Nocebo, and Simultaneous Treatment Expectation
Manipulation ...... 22
2 Pilot Study ...... 23
2.1 Overview ...... 23
2.2 Main Hypotheses ...... 24
2.2.1 Task Engagement ...... 24
2.2.2 Threat and Challenge Responding ...... 24
2.2.3 Alternate Uses Test Performance ...... 26
2.3 Method ...... 27
2.3.1 Participants and Design...... 27
2.3.2 Measures and Procedure ...... 27
2.3.3 Health History and Demographics ...... 27
2.3.4 Cardiovascular Measures ...... 28
2.3.5 Mind Clearing Resource Manipulation ...... 28
2.3.6 Alternate Uses Test ...... 29
2.3.7 Procedure ...... 30
2.4 Results ...... 31
2.4.1 Physiological Data Acquisition...... 32
2.4.2 Analysis of Task Engagement ...... 32
2.4.3 Analysis of Threat and Challenge ...... 34
2.4.4 Alternate Uses Test Performance ...... 36
2.5 Discussion ...... 37
3 Current Research ...... 39
vii 3.1 Overview ...... 38
3.2 Main Hypotheses ...... 40
3.2.1 Task Engagement ...... 40
3.2.2 High Resource and Low Demand ...... 41
3.2.3 Low Resource and High Demand ...... 42
3.2.4 High Resource High Demand ...... 42
3.3 Alternate Uses Test ...... 43
3.4 Method ...... 44
3.4.1 Participants and Design...... 44
3.4.2 Materials and Measures ...... 44
3.4.2.1 Health History Questionnaire and Demographics ...... 44
3.4.2.2 Cardiovascular Measures ...... 45
3.4.2.3 Alternate Uses Test ...... 45
3.4.2.4 tDCS Resource Manipulation ...... 45
3.4.2.5 Placebo Demand Manipulation ...... 47
3.4.2.6 Supplementary Questions ...... 48
3.4.2.7 Manipulation Check Item ...... 48
3.4.3 Procedure ...... 49
4 Results ...... 51
4.1 Overview ...... 51
4.2 Manipulation Check Analysis ...... 51
4.3 Physiological Data Acquisition...... 53
4.3.1 Analysis of Task Engagement ...... 54
viii 4.3.2 Analysis of Threat and Challenge ...... 57
4.4 Alternate Uses Test Performance ...... 61
4.5 Analysis of Supplementary Questions ...... 63
4.5.1 Individual Differences ...... 65
4.5.2 Excluded Participants...... 69
5 Discussion ...... 70
5.1 Overview ...... 70
5.2 Manipulation Check Data ...... 71
5.3 Task Engagement Hypothesis ...... 72
5.4 Physiological Baseline Threat and Challenge Hypothesis ...... 72
5.4.1 Physiological High Resource and Low Demand Hypothesis ...... 72
5.4.2 Physiological Low Resource and High Demand Hypothesis ...... 74
5.4.3 Physiological High Resource and High Demand Hypothesis...... 74
5.5 Alternate Uses Test Hypothesis ...... 75
5.6 Supplementary Questions ...... 76
5.7 Individual Differences Moderators and Mediators ...... 77
5.7.1 Moderation ...... 77
5.7.2 Mediation ...... 79
5.8 Discussion of Non-Significant Results ...... 80
5.8.1 Resource and Demand Manipulations ...... 81
5.8.2 tDCS Resource Addition...... 82
5.8.3 Performance Domains ...... 84
5.8.4 Motivation Issues ...... 85
ix 5.8.5 Sample Characteristics ...... 87
5.9 Other Placebo Paradigms ...... 88
5.10 Challenge and Threat as Continuous or Dichotomous ...... 89
5.11 Meaningful Real-World Application ...... 90
5.12 Conclusion ...... 90
References ...... 92
Appendices ...... 105
A. Personal Health History ...... 105
B. Alternate Uses Test ...... 106
C. Supplementary Questions ...... 107
D. Funnel Debriefing ...... 115
E. Consent Form ...... 116
F. Evaluation of Challenge Script for Dissertation ...... 118
x List of Tables
Table 1: Manipulation Check Question by Experimental Condition ...... 53
Table 2: Task Engagement Correlations ...... 55
Table 3: Mean Task Engagement for HR, PEP, and Combined ...... 57
Table 4: Correlations between Alternative Uses Task Period Measures...... 58
Table 5: Mean Threat/Challenge for TPR, CO and Combined ...... 61
Table 6: Mean Alternate Uses Test Performance ...... 63
Table 7: Mean Ratings of Whether Participants were Anxious during tDCS ...... 64
Table 8: Mean ratings of Performance State Self-Esteem ...... 65
Table 9: Ten Item Personality Measure Conscientiousness ...... 67
Table 10: Ten Item Personality Measure Openness to Experience ...... 68
xi List of Figures
Figure 1: Overview of the Biopsychosocial Model (Seery, 2011) ...... 5
Figure 2: Pilot Study Challenge Responding by Condition ...... 36
Figure 3: Task Engagement by Experimental Condition ...... 56
Figure 4: Challenge Responding as depicted by Condition ...... 60
Figure 5: Number of Alternate Uses Stated by Condition (Fluency) ...... 62
Figure 6: Challenge Responding by Openness to Experience ...... 69
xii List of Abbreviations
BP…….……….Blood Pressure BPS Model…....Biopsychosocial Model
CO…………….Cardiac Output
ECG……….…..Electrocardiograph
HR…………….Heart Rate
ICG…………....Impedance Cardiography
MAP……….….Mean Arterial Pressure
PAC…………...Pituitary-Adrenal-Cortical PEP……………Post Ejection Period
SAM…………..Sympathetic-Adrenal-Medullary SCT…………...Stress and Coping Theory SV…………….Stroke Volume tDCS………….Transcranial Direct Current Stimulation TPR…………...Total Peripheral Resistance
VC…………….Ventricular Contractibility
xiii Chapter One
Introduction
1.1 Project Overview
The Biopsychosocial Model of Threat and Challenge (BPS; Blascovich &
Tomaka, 1996) informs research on stress and coping. The present research proposes a new application of this conceptual model: To explain occurrences of placebo and nocebo effects. It is argued here that the processes outlined in the BPS model, concerning how people cope and respond to stress, can be employed to explain how in some cases placebo and nocebo effects arise.
The present paper begins with an overview of Stress and Coping Theory and the
BPS model as this model serves as the basis for the proposed study. From here, discussion shifts to a brief overview of placebo and nocebo effects to provide the reader with a background of the phenomena under investigation. The phenomena of placebo and nocebo effects are then synthesized with the Threat and Challenge BPS Model. Pilot
Study research, testing the integration between placebo effects and the BPS model, is described and explained. Finally, an experiment made from this integration is analyzed and discussed.
1.2 Stress and Coping Theory
Psychological literature has often focused on how people manage stress (Ray,
Lindop, & Gibson, 1982). Individuals experience stress when internal perceptions or external pressures are perceived as exceeding one’s ability to cope (Seery, 2013). Stress can have both positive and negative psychological consequences. Stress can be beneficial when it is temporary and lasts only for a limited amount of time; stressful experiences in
1 the short-term lead to increased productivity given the right circumstances (Seery, 2013).
Conversely, experiencing stress without adequate coping resources can be detrimental and interfere with healthy functioning, as an inability to cope can lead to mental and physical deteriorations (Lovallo, 2015). Stress can be persistent (constant) or temporary where the effects of many short bursts of stress can build up over time. Persistent stress, and the buildup of temporary stress, can be detrimental as it yields physical and psychological harm. Stress is associated with increased fat intake, little exercise, and smoking (Ng & Jeffery, 2003). Further, chronic stress is associated with immune suppression, cold development, heart disease, and cancer (Cohen, Frank, Doyle, Skoner,
Rabin, & Gwaltney, 1998; Baum & Posluszny, 1999; Pandya, 1998; Stahl & Hauger,
1994; Tennant, 2000). As such, alleviation of stress through coping is vital to healthy human functioning. Coping refers to the way individuals respond to stress. More specifically, coping can be defined as the various cognitive and behavioral strategies individuals employ to manage external and/or internal demands that are considered taxing (Folkman, Lazarus, Dunkel-Schtter, DeLongis, & Gruen, 1986). Typical components of the coping process include cognitively judging an event to be stressful, feeling overwhelmed, and causing one to behave in response to the stressful event
(Snyder, 1999).
To fully understand the present focus on coping, one of the major coping theories is explained: Lazarus and Folkman’s Stress and Coping Theory (SCT; 1984). SCT examines cognitive appraisal and coping. SCT accounts for the association between stressful person-environment encounters as well as the long and short-term consequences mediated by cognitive appraisal and coping (Folkman et al., 1986).
2 SCT relies heavily upon cognitive appraisal, a process by which an individual determines the relevance of one’s environmental encounters to one’s welfare. Cognitive appraisal consists of both primary and secondary appraisals. These two forms of appraisal can occur simultaneously and are not meant to occur sequentially. During primary appraisal, the individual determines if s/he has anything to lose in this situation (e.g. harm). Within primary appraisal individuals assess if stressors present a threat. Secondary appraisal extends past answering initial questions, such as “will I be harmed?” During secondary appraisal, individuals determine if there is any way in which harm to one’s well-being can be evaded, or if one could be benefitted instead. This is where coping enters the SCT.
Coping strategies involve adapting to a situation by seeking more information or holding back from acting thoughtlessly (Folkman et al., 1986). Both primary and secondary appraisals determine if the stressful person-environment encounter is relevant to one’s well-being and if one has the resources to surpass the stressor. When this occurs, the person-environment relationship is determined to be challenging or threatening.
Threat here could result in “harm or loss,” while challenge is viewed positively, possibly leading to success or other benefits (Folkman et al., 1986). As anticipation builds, primary and secondary appraisals can occur a priori to stressful situations (Takoma,
Blascovich, Kelsey, & Leitten, 1993). Appraisals of threat are associated more with negative emotions than challenge appraisals (Fischer, Shaver, & Carnochan, 1990;
Folkman and Lazarus, 1985; Kobasa, 1982).
In summary, stress and the subsequent coping mechanisms engaged to deal with this stress have been a focus of much theory and research. Coping involves the cognitive
3 or behavioral strategies used to handle challenging internal and/or external demands.
Lazarus and Folkman’s SCT (1984) employs cognitive appraisals and coping to help explain the consequences of stressful person-environment encounters. Threat and challenge are cognitive appraisals by which the person-environment relationship is evaluated.
1.3 Connecting the Stress and Coping Theory to the Biopsychosocial Model
A more recent model in the literature that developed from Lazarus and Folkman’s
Stress and Coping Theory (SCT; 1984) is Blascovich’s Biopsychosocial Model (BPS
Model; 1996). The BPS Model begins from the SCT perspective by distinguishing between two key reactions to stress: challenge and threat. The BPS model also views challenge as more affectively positive and threat as more affectively negative. In discriminating between the two, the creators of the BPS Model use the term “evaluation,” rather than “appraisal” to describe affective processes (i.e., feelings of threat or challenge; Seery, 2011). Appraisals are the intervening processes, involving primary and secondary appraisals, for SCT whereas challenge and threat evaluations are the output event for the BPS Model. This model is presented in Figure 1.
Seery and colleagues (2011) extend the SCT (Lazarus & Folkman, 1984) in several key ways. First, the BPS Model (Blascovich & Tomaka, 1996), challenge and threat evaluations are the key end product of the primary and secondary appraisal processes. A difference between theories lies in when one perceives feelings of threat or challenge: SCT focuses on feelings occurring alongside appraisal and the BPS Model focuses on feelings occurring after appraisal. Second, the BPS Model and SCT focus on different outcomes. SCT predictions are focused on psychological and behavioral
4 outcomes. The BPS model emphasizes physiological reactions. Within the BPS model, psychological states of challenge and threat are thought to result in predictable patterns of physiological reactions. Finally, divergent challenge and threat reactions only occur in the BPS Model when a motivated performance situation is self-relevant. In comparison,
Lazarus argues that the threat/challenge perception influences whether a circumstance is judged as self-relevant (Seery, 2011).
Figure 1. Overview of the Biopsychosocial Model (Seery, 2011).
5 1.4 Biopsychosocial Model of Threat and Challenge
The BPS model has proven valuable in guiding research and has been evaluated in multiple domains including social stigma, athletic performance, information processing, and social comparisons (Blascovich, Mendes, Hunter, Lickel, & Kowai-Bell,
2001; Blascovich, Seery, Mudridge, Norris, & Weisbuch, 2004; Hunter, 2001; Mendes,
Blascovich, Major, & Seery, 2001). The BPS Model makes predictions regarding coping processes through specific physiological measures of impedance cardiography that are indicative of coping (Fonseca, Blascovich, & Garcia-Marques, 2014). These measurements are key, as the model does not merely rely on self-report which can often stem from other, non-coping related processes (e.g., demand characteristics; Orne, 1962).
Rather, raw physiological changes in the body can inform researchers whether someone is coping effectively or not. Specifically, this model can determine the effectiveness of coping when the stressful situation is important to the affected person. Next, I describe the BPS model in detail.
1.4.1 Task Engagement
The BPS Model (Blascovich & Tomaka, 1996) focuses on challenge and threat coping reactions for self-relevant tasks, tasks in which performance motivation is increased. The general notion that the activation of pivotal psychological and physiological processes begins with self-relevance is consistent with a wide array of prominent theories in psychology (e.g., Fiske & Neuberg, 1990; Heider, 1958; Kunda,
1990; Petty & Cacioppo, 1986). Motivated performance situations refer to self-relevant tasks or other performances in which an individual is engaged and invested (Blascovich,
Mendes, Hunter, & Lickel, 2000; Elliot, 2008), such as performance on a test at school,
6 responding to a medical diagnosis, or adapting to a new treatment regimen. When a task is important participants believe that satisfactory or unsatisfactory performance means something about themselves (e.g., stress tests, dieting, weight loss, social skills;
Blascovich & Tomaka, 1996). Further, task relevance can be enhanced through evaluation by others. When individuals believe that their performance is being monitored by someone, such as a peer or experimenter, task engagement is strengthened (Blascovich et al., 2000). Increased engagement and investment signal motivation toward goal attainment when various situational demands are encountered. When positive performance is desired the body prepares metabolically for demanding physical activity.
As such, changes in engagement can be directly attributed to changes in stressful stimuli.
1.4.2 Resources and Situational Demands
The BPS model suggests that when engaged in a self-relevant task, people respond differently based on perceived resources and situational demands (Seery, 2013).
In terms of the BPS model, when an individual perceives their resources to exceed situational demands, he or she believes they can overcome the situation and would thus exhibit more of a challenge response. However, when situational demands exceed resources, a threat response is displayed. Research on the BPS model has mostly focused on external resources, such as competition, task performance, and external support
(Blascovich, Mendes, Tomaka, Salomon, & Seery, 2003). Nevertheless, the model also readily acknowledges that resources can be internal, including medical knowledge, skills and abilities; or external, including social support, instrumental provisions/assets, and access to medication (Blascovich et al., 2004). Situational demands refer to the physical or mental taxes caused by a situation, effort required to succeed, and of the perception of
7 increased danger and uncertainty (Blascovich et al., 2004). Challenge and threat reactions are determined by whether a person’s coping resources are perceived as greater than or less than the resources needed to cope with stress, respectively. Thus, according to the model, self-relevant tasks can lead to either threat- or challenge-style responses depending on the balance of perceived coping resources and situational demands.
1.4.3 Threat and Challenge
In Blascovich and Tomaka’s (1996) BPS model, challenge and threat can be conceptualized as the poles of a bidirectional continuum. For example, if an individual perceives their resources as exceeding the demands of a situation, that individual would psychophysiologically experience more affectively positive challenge responding. As a result, the individual would experience less affectively negative threat responding.
Challenge evaluations encompass positive reactions and lead to increase task engagement, which can sometimes improve performance. That is, challenge may increase the willingness to expend mental and behavioral effort on self-relevant tasks and can consequently result in greater levels of task engagement and performance outcomes if the tasks are sensitive to effort expenditures (Chalabaev, Major, Cury & Sarrazin, 2009; Seta,
Seta, & Donaldson, 1991; 1992). Further, threat responses yield different psychological and behavioral consequences than challenge responses and yield more negative outcomes that do not increase task performance. For example, students who consider themselves unprepared for an exam may feel threatened and anxious. These students would then perform worse on the exam. Students who feel prepared, on the other hand, would do better as a product of feeling more confident and challenged.
8 1.4.4 Biopsychosocial Model Measurement
The BPS model focuses on how the human physiological system is altered by psychological interpretation of the task. Through this model, researchers can concretely investigate how psychological perceptions generate changes to environmental stimuli. In prior research on the BPS model, physiological responses have been validated as measures of challenge and threat (Blascovich & Tomaka, 1996). Self-report measures provide perspective from the person and can supplement physiological recordings and have been used successfully in prior studies (e.g., self-reported life stressors, task stressors, and affect). However, due to the variables, such as demand characteristics and response biases, as well as the documented problems individuals can have when inaccurately reporting on their internal motives (Nisbett & Wilson, 1977), the BPS model also concerns physiological recordings which capture additional information for researchers than just self-report alone.
As depicted in Figure 1, threat and challenge responses are hypothesized to result in distinct physiological responses (Blascovich & Tomaka, 1996). Physiological changes can be measured in performance situations when the body is preparing for metabolically demanding physical activity (which may or may not follow). The physiological challenge pattern within this model depicts increased activity in the sympathetic-adrenal-medullary
(SAM) axis. Dienstbier (1989) asserted that SAM activation is a bodily reaction to motivated performance situations in the short term only (a few mins). SAM activity is in contrast with pituitary-adrenal-cortical activation (PAC), which accounts for cortisol release and break down for over an hour (Seery, 2013; Dienstbier, 1989). When challenged, one gains confidence and actively pursues a desired goal. The cardiovascular
9 pattern exhibited by challenge differs from threat and is akin to responses seen in physical exercise (Seery, 2013). Challenge is marked by a decrease in total peripheral resistance (TPR; compares net values of constriction and dilation of arterial pressure;
Blascovich et al., 2004) and an increase in cardiac output (CO; measurements record the total number of liters of blood the heart pumps per min; Seery, 2013) similar to that which occurs in aerobic exercise.
In contrast, the cardiovascular pattern of threat readies the body for action and physical inhibition simultaneously (e.g., not moving to avoid detection as an animal might do if a threat were near). A threatened individual must be alert as the cardiovascular pattern results in continued goal pursuit progress, but also in physiological readiness to abandon goal pursuit at any moment (Seery, 2013). An increase in ventricular contractibility (VC; a measurement of the contracting force of the left ventricle; Seery, 2013) and heart rate (HR) signal task engagement for both challenge and threat. Finally, blood pressure remains relatively stable during challenge conditions
(Blascovich & Mendes, 2000).
The physiological markers of threat differ from that of challenge. When both the
SAM axis and the PAC axis increase in activity, more threat is found. Threat is accounted for by min changes in both CO and TPR as PAC activity dampens SAM responses, inhibiting movement (Seery, 2013). Large changes in blood pressure are recorded when one experiences threat (Blascovich & Mendes, 2000). Measures of HR, VC, CO, TPR and BP all converge to distinguish between threat/challenge and determine task engagement. Challenge is marked by low TPR and high CO, whereas threat is marked by high TPR and low CO. Task engagement is high if VC and HR are increased.
10 1.4.5 Domains of Biopsychosocial Model Application
Although it is important to understand how physiological markers are recorded and interpreted, discussion of BPS model recording domains are equally important. For example, researchers examined athletic performance in terms of challenge and threat using the BPS model (Blascovich et al., 2004). Athletes gave a speech on a sport-relevant or sport-irrelevant topic while cardiovascular measures were recorded. Situational demands remained constant and resources were manipulated. Consistent with the BPS model, sport-relevant speeches resulted in physiological responses associated with task engagement. Importantly, the speeches also produced physiological responses of challenge and challenge responses predicted better athletic performance during the season than sport-irrelevant speeches.
Threat and challenge responding has also been examined in other domains, including social interactions between White and Black men (Mendes, Blascovich, Lickel,
& Hunter, 2002). White or Black race confederates stated they were advantaged or disadvantaged socioeconomically during a social interaction with participants who were not Black. Physiological measures of threat and challenge were recorded, and task engagement was confirmed through increases in HR reactivity across conditions.
Participants experienced more threat when conversing with a Black, disadvantaged confederate. Participants also experienced more challenge when interacting with a White, advantaged confederate. Behavioral measures of cooperative task performance were also measured. Consistent with the BPS model, challenged participants did better on the cooperative performance task when paired with a White partner rather than a Black partner.
11 Pertinent to the present research is a recent study on the BPS model by Seery,
Weisbuch and Blascovich (2009). This study is very relevant as the paradigm used serves as the basis for the Pilot Study discussed in this dissertation. Seery and colleagues drew together the concept of message framing (for reviews see Updegraff & Rothman, 2013;
Gallagher & Updegraff, 2012) with the physiological markers used to assess threat and challenge. At the start of the study, baseline cardiovascular measures were recorded.
These measures included a Minnesota Impedance Cardiograph and a Cortronics Blood
Pressure Monitor which was continuously inflated. After baseline measures were recorded, participants were given instructions on the Remote Associates Test (RAT;
McFarlin & Blascovich, 1984) and a message framing manipulation. The RAT is a standard cognitive performance task which was described as a “reasoning ability” test.
The RAT consists of naming a word in an allotted amount of time that connects three other words together. For example, “widow, bite, and monkey” were all correctly connected by the word “spider” (Mednick, Mednick & Mednick 1964). Seery and colleagues presented twelve sets of these words to participants in fifteen second intervals for a total of 3 mins. The cardiovascular measures used at baseline were recorded throughout the task.
Prior to the main RAT performance, the researchers employed a message framing manipulation. For the framing manipulation, gain condition participants were told, “in order to encourage your best performance, we are offering a $5 incentive. You will begin with no money, but you will win $.50 for each item that you answer correctly” (Seery, et al., 2009, pp. 310). In contrast, participants in the loss condition were instructed “…you will begin with $5, but you will lose $.50 for each item that you skip or answer
12 incorrectly” (Seery et. al, 2009, pp. 310). Finally, in addition to the gain and loss frame conditions, this study also contained a control condition in which participants were given no incentive for performance.
Results demonstrated that the framing conditions differed from the control in that participants had larger increases in HR and larger decreases in pre-ejection period from baseline. This signals high task engagement in the framing conditions regardless of whether the gain or loss frame of the monetary incentive was employed. These results also indicated that the framing participants were engaged in the task, a necessary component of the BPS Model (Blascovich & Tomaka, 1996). Importantly, the cardiovascular measures of threat and challenge were found to be sensitive to the framing manipulation. Specifically, this study found that the gain frame resulted in higher CO and lower TPR (i.e., markers of challenge) than the loss frame. This indicates participants provided with a positively framed message evaluated the task as more challenging, whereas those provided with a loss frame evaluated the task as more threatening. The results indicate that how task instructions are framed can be a critical determinant of whether individuals respond with a threat or challenge. Gain (positive) frames appear to lead to more challenge responses, whereas loss (negative) frames appear to lead to more threat responses.
1.4.6 Biopsychosocial Model and Placebo Effects
The BPS model is traditionally studied and applied to performance and social contexts. These contexts, as described above, include sport performance, interactions between White and Black men, and conversations with confederates (Blascovich et al.,
13 2004; Mendes et al., 2002). However, as the model is broad and was devised to cover a wide array of situations, it has potential to shed light on issues in numerous other arenas.
Critically, prior research reveals that simply believing oneself is undergoing a treatment can bring about a multitude of psychological and physiological changes, collectively called placebo effects. It is suggested here that our understanding of when placebo effects manifest and of the processes underlying them in health care contexts can be increased by integrating the placebo effect concept with the BPS model. Specifically, it may be possible to use the BPS model to understand psychological responses to treatment administration that, in turn, alter physiology. The main goal of the present work is to provide preliminary data on this issue.
1.5 Placebo Effects
Placebo effects are defined as psychological or physiological changes in response to receiving a substance or undergoing a procedure that cannot be attributed to the actual treatment itself (Stewart-Williams & Podd, 2004). Placebos are inactive treatments that produce positive results due to purely psychological variables. Historically, placebo effects were defined as the result of inert treatment administration. Based on a growing body of research, placebo effects now encompass the positive expectations and interpretations of an individual surrounding a provided treatment (Benedetti, 2009).
Placebo effects thus become one’s positive perceptions and evaluations surrounding treatments, especially in a health care setting (Benedetti, 2009).
Placebo effects can be isolated in experiments where responses to treatment efficacy messages (e.g., this pill will reduce your pain) are compared to responses of a control group who did not receive the efficacy message. Without comparison to a control
14 group, observed benefits are not clearly placebo effects, but could also result from spontaneous remission, history effects, and regression to the mean (Geers & Caplandies, in press). A placebo response refers to a specific change that occurs to an individual’s symptoms or condition because of the administration of a placebo (Price, Finniss, &
Benedetti, 2008). Placebo effects are often found on subjective measures of mood, pain, depression, headache, and sleep quality (For a review, see Geers, Brinol, Brown, & Petty, in preparation). Behavioral measures including pain tolerance, completion of puzzle tasks, reduced sleep latency, accuracy on search tasks, weight lifting by competitive lifters, and motor performance in Parkinson patients have been found to yield placebo effects (e.g., Geers et al., in preparation; Shiv, Carmon, & Ariely, 2005; Wellman &
Geers, 2009). Measures of cognitive processing have also captured placebo effects, including measures of reaction time, recall, recognition, Stroop interference, and implicit learning (e.g., Gama, Slama, Caspar, Gevers, & Cleeremans, 2013; Geers, Wellman,
Fowler, Rasinski, & Helfer, 2011; Colagiuri, Livesev, & Harris, 2011; Wright, Mauro da
Costa Hernandez, Sundar, Dinsmore, & Kardes, 2013). Recent research has also connected neurobiological pathways and placebo effects. For example, brain imaging studies have shown that placebos analgesics activate the same neural networks and endogenous opioid pathways as pharmacological treatments for pain (For reviews, see
Atlas et al., 2009; Benedetti, 2009; Enck, Bingel, Schedlowski & Rief, 2013). Placebo treatments have also been found to modify nociceptive mechanisms in the spinal cord
(For reviews, see Eippert, Finsterbusch, Bingel, & Buchel, 2009; Goffaux, Redmond,
Rainville, & Marchand, 2007; Matre Casey & Knardahl, 2006). Placebo effects are
15 highly applicable to health and medical outcomes and emerge across a variety of diverse domains.
Although placebo effects occur in a multitude of symptom and performance domains, placebo research has focused considerable attention on pain and stress. This focus appears to be the result of strong placebo effects in these domains as well as the potential benefits for reducing pain and stress in clinical situations. Example placebo– pain paradigms include heat-induced pain, electric shock, submerging one’s hand in ice cold water for two mins, listening to aversive noises through headphones, ischemic pain tasks, ingestion of supposed pain-reducing pills, and perceived direct cranial stimulation
(Caplandies, Collaguri, Helfer, & Geers, 2017; Colloca & Benedetti, 2009; Geers, Helfer,
Kosbab, Weiland, & Landry 2005; Geers, Wellman, Fowler, Helfer, & France, 2010;
Geers, Wellman, Helfer, Fowler, & France 2008; Price, Milling, Kirsch, Duff,
Mongomery, & Nicholls, 1999; Rose, Geers, Rasinski, & Fowler 2012; Rainville, Feine,
Bushnell, & Duncan, 1992; Wager el al., 2004). Placebo effects using these paradigms are typically assessed by cardiovascular measures, fMRI recordings, and online ratings of pain, discomfort, or stress.
Important for the present study, substantial prior research indicates that providing treatment expectations to individuals significantly reduces stress and pain when compared to individuals who do not receive a treatment expectation (for a review, see
Colloca & Grillon, 2014; Price et al., 1999). Expectations are our beliefs about the probabilities associated with a future state of affairs (Olson, Roese, & Zanna, 1996).
According to Response Expectancy Theory (Kirsch, 1999), placebo effects are directly caused by the belief that one’s treatment experience can be confirmed by a specific
16 outcome. Expectations are thought to serve the function of preparing individuals for future outcomes. Generally speaking, perceptions of receiving a treatment yield psychological and physiological responses in line with an expectation—the placebo effect.
With placebo treatments, people have an expectation about the efficacy of the treatment (i.e., whether the treatment will work) and engage in search processes looking for evidence confirming their expectation (i.e., searching for evidence that a treatment is working). Treatment expectations thus become the main way in which individuals can assess efficacy (for related arguments, see Aarts & Dijksterhuis, 2000; Shah &
Kruglanski, 2003). Expectancy-confirmation search can result in changes in sensation detection, symptom appraisals, symptom attributions, and memory for symptoms (Brody
& Brody, 2000; Geers, Weiland, Kosbab, Landry, & Helfer, 2005; Kirsch & Sapirstein,
1998; Ross & Olson, 1981). For example, Geers et al. (2012) found that placebo expectations increase the perception of expectation-congruent symptoms and reduces the perception of expectation-incongruent symptoms. Other potentially overlapping pathways linking treatment expectations to placebo effects include anxiety reduction and increases in positive/reward processing (Geers & Rose, 2011; Atlas, Wager, Dahl, & Smith, 2009;
Benedetti, 2008). For example, positive treatment expectations may cause individuals to selectively attend to signs of improvement, feel less anxious, and experience a more positive feeling state.
Although there has been a shift toward using neurobiological measures to assess placebo effects (for a review, see Benedetti, Mayberg, Wager, Stohler, & Zubieta, 2005)
Placebo research relies on subjective responses and measures. A benefit of the BPS
17 model is that non-subjective cardiovascular measures are predicted to depict distinct psychological and physiological outcomes. Marrying these subjective and non-subjective measurements together, one’s perception of a positively valenced placebo treatment can be altered and influence physiological responding along the threat/challenge continuum toward more challenge. As a result, the BPS model can be used to understand how placebo effects manifest from coping processes.
1.5.1 Placebo Treatment Expectation Manipulation of Resources
As depicted in the diagram of the BPS model in Figure 1, one can either progress towards challenge or threat based on the perception of resources and situational demands
(Blascovich & Mendes, 2000). Placebo provision may alter one’s perception of resources and therefore change which psychophysiological pathway of the BPS model is taken. It is suggested here that a treatment expectation (the cause of placebo effects) could increase perceived resources and thereby help an individual to cope more effectively (a challenge response). Advantageous coping responses could then be considered the end result of a process whereby the perception of resources alters coping responses that lead to positive outcomes (i.e., a placebo effect). That is, perception of a treatment may alter the momentary evaluation of resources. This perception could shift individuals toward challenge responses, as outlined in the BPS model. Importantly, in studies testing for placebo effects, the addition of a placebo treatment would only alter resource perception, not the actual resources themselves. For example, providing a placebo treatment
(resource) could cause one’s perception of resources to be more beneficial. A patient who received a placebo pill (resource) for pain would be predicted by the model to be more challenged than a patient who was not provided a placebo pill (no resource) for pain.
18 It must be noted that the threat/challenge model predictions were not expected to account for all placebo effects. Rather, this is a complex phenomenon that is likely multi- determined depending on the situation or context. The focus here is on how the coping processes described in the threat/challenge model can explain some of the variance in stressor and performance placebo situations. However, this model may not be able to account for responses in other situations when treatment responses were due to conditioning, or when the treatment event involves no stress.
1.6 Nocebo Effects
Nocebo effects can be defined as negatively-valenced placebo effects stemming from unpleasant treatment outcome anticipation (Geers & Caplandies, in press; Kennedy,
1961). Defining nocebos as negatively-valenced placebo effects allows for placebo and nocebo effects to be conceptualized as two distinct ends of a bidirectional continuum where one is considered to be more positive and the other more negative. On one end, positive instructions can enhance responses to inert treatments, whereas negative instructions can lead to worsening symptoms on the opposite end of the continuum.
Nocebo effects have been found on self-report, physiological and neurobiological measures (Colloca & Benedetti, 2016). Prior research on nocebo effects involves nausea and fatigue in chemotherapy patients, motor performance in patients with Parkinson’s disease, inert sleep treatment side effects, unpleasant symptoms from wind turbines, and pain in patients and healthy volunteers (Benedetti, 2014; Colloca, Flaten, & Meissner.,
2013; Crichton & Petrie, 2015). Nocebo effects may manifest from a variety of medical treatment-related information provided to patients. For example, nocebo effects may arise from the mere presentation of information regarding potential adverse treatment effects
19 when patients are exposed to drug side effect information, direct-to consumer medical advertising, and informed consent protocols (Doering & Rief, 2013; Myers, Cairns, &
Singer, 1987; Faasse, Grey, Jordan, Garland & Petrie, 2015).
1.6.1 Nocebo Treatment Expectation Manipulation of Situational Demand
In addition to using the BPS model to explain placebo effects, the present research aims to address how the BPS model could be used to explain nocebo effects. The logic for linking the BPS model to nocebo effects is similar to that linking this model to placebo effects. That is, nocebo responses could stem from perceptions of low resources and high situational demands, labeled in the BPS model as a threat response.
Recall that situational demands refer to the physical or mental taxes caused by a situation, effort required to succeed, and include the perception of increased danger and uncertainty (Blascovich et al., 2004). It is suggested here that features of different treatment events are factors that influence the demand of a situation (making it more or less demanding). For example, a patient who is told a procedure will be painful
(increased situational demand) would experience a greater threat than a patient who was not told a procedure will be painful.
If nocebo effects can be predicted using the BPS model, an important step toward nocebo effect reduction could occur. For example, perceiving that a treatment may be taxing through increasing demand (e.g., this drug will make you feel nauseous) provides the perception of threat. Evidence suggests that strongly emphasizing treatment benefits over side effect warnings may weaken nocebo expectations (Heisig, Shedden-Mora,
Hidalgo, & Nestoriuc, 2015). Emphasizing treatment benefits could be considered a resource provided to patients to shift them away from threat and towards more challenge.
20 1.7 Simultaneous Manipulation of Resources and Demands
As described above, the primary aim of the present research is to assess the viability of the BPS model to explain both placebo and nocebo effects. In addition to this aim, the project is designed to address a second, more subsidiary aim. The second aim concerns an unresolved issue with the BPS model: how resources and demand perceptions interrelate. That is, at present, little to no research has orthogonally manipulated perception of demands and resources. Rather, in the BPS literature, only one of these variables is manipulated with the other held constant. It may be the case that manipulating both situational demands and resources could help account for differences in coping. For instance, in the domain of medical treatment responses, it seems likely that both resource and demand perceptions are altered by contextual features. As an example, consider a patient who has undergone gastric bypass surgery and must adhere to a strict diet to avoid severe illness. The requirement to eat well would create a high situational demand. However, this patient would also have high resources to cope with the need to eat well because gastric bypass patients endure three months of pre-operative compliance training. During this time, patients are provided all the resources needed to succeed. This situation would correspond to individuals having both high demand and high resources. It could be, however, that in other cases these resources are not made available. As such, it could be that there are high demand and low resources. In this way, we could identify cases in which resources and demand create a 2 (resource: high vs. low) x 2 (demand: high vs. low) matrix. It is possible that scenarios where resources and situational demands both diverge may yield different BPS model coping responses to treatment than previously predicted non-equivalence (standard model predictions). As such,
21 understanding the different ways stress and coping processes manifest, can result in the best possible treatment across a variety of medical situations.
1.8 Aim of Placebo, Nocebo, and Simultaneous Treatment Expectation
Manipulation
First, present research aims to address how placebo treatment expectations and nocebo treatment expectations work to better understand resources and situational demands within the BPS model. Evidence for different strengths of a placebo response through threat and challenge responding, where more challenge is considered a stronger placebo response (Pilot Study and Main Study) and more threat is considered a stronger nocebo response was assessed (Main Study). By manipulating both resources and demands (Main Study), present work is designed to capture placebo and nocebo effects in the same paradigm which has not been done before.
Second, prior work within the BPS model has not addressed coping responses when perceived resources and situational demands are equivalent (i.e. either both high or both low). Although the BPS model does not directly address this issue, the model does predict that when resources are perceived as exceeding situational demands, a challenge response occurs. Conversely, more of a threat response is predicted by the model when situational demands are perceived to outweigh resources. Following this logic, it is predicted that both high resources and high demands should yield a challenge response akin to a placebo effect, albeit not as much challenge as high resources and low demands.
It is further predicted that both low resources and low demand could result in a neutral, control like response where responses would fall in the midpoint of both the threat/challenge and placebo/nocebo continuums.
22 Chapter Two
Pilot Study
2.1 Overview
A pilot study was conducted to examine the possibility that the BPS model could help account for placebo effects in performance situations. According to the BPS model, individuals experience more of a challenge response if they view themselves as having enough resources to handle the task, or a threat response if they do not. If a treatment expectation is conceptualized as an asset, akin to perception of greater resources, then integration of the placebo literature with the challenge threat model is useful. In line with the Seery et al. (2009) study described earlier, the present Pilot Study examined how the wording of a placebo expectation (gain or loss-framed) about the difficulty of a performance task determined whether an individual experiences a challenge or threat response to the task. This was tested in the present study using a performance paradigm successfully employed in research inducing stress (alternate uses test; Guilford, 1967). In the Pilot Study, participants were fitted with physiological measures of impedance cardiography and completed a brief mind clearing exercise before completing a difficult word task. Prior to the word task, participants were randomly assigned to one of three conditions in which participants were provided an expectation that the mind clearing task would help them to perform better on the word task (gain frame), not perform as poorly on the word task (loss frame), or that the mind clearing was a part of normal physiological baseline recordings (control condition). Here, the gain frame and loss frame conditions are considered to be placebo expectations. In both expectation conditions,
23 participants are provided a resource beyond that of the control condition which was expected to increase challenge responding.
2.2 Main Hypotheses
2.2.1 Task Engagement
According to the BPS model, threat and challenge cannot be adequately assessed if task engagement is not present, thus in testing for physiological differences in threat and challenge, participants were first assessed for evidence of task engagement. Two predictions regarding task engagement were hypothesized. First, increased engagement and investment signal motivation toward goal attainment when faced with various situational demands. When positive performance is desired, physiologically, the body becomes more engaged. Changes in engagement can be directly attributed to changes in stressful stimuli (e.g. treatment expectations) and are predicted therefore to not be present during physiological recordings prior to treatment at baseline. Second, it was expected that all participants would be equally engaged during the alternate uses test. No condition main effect or interaction was anticipated, as all groups were expected to display task engagement.
H1a: Using physiological measures assessing task engagement, participants would not display changes in task engagement during the baseline recording period.
H1b: Using physiological measures assessing task engagement, participants would not differ from one another in task engagement during the alternate uses test.
2.2.2 Threat/Challenge Responding
First, it is theorized here that in placebo paradigms, the administration of the placebo manipulation is akin to providing an individual a resource to cope with a stressor.
24 That is, the expectation of a treatment (placebo or active) can be conceptualized as a resource that allows one to make a challenge rather than threat evaluation. As such, control participants (no expectation) were compared with treatment expectation participants. It is expected that control participants (those not given the treatment expectation) would display more of a threat pattern of physiological reactions than expectation participants. If these results were found, it would provide preliminary evidence that placebo effects in performance situations can be the result of differences in challenge and threat evaluations.
Second, in the present study, a framing manipulation was also used to alter how participants perceive the placebo expectation. Seery et al. (2009) found that gain
(positive) frames can result in challenge responses. Following this finding, a gain frame expectancy (e.g., you will perform better) was hypothesized to lead to more of a challenge response and better performance on the alternate uses test, whereas the control condition (no expectation) was expected to lead to more of a threat response and worse performance on the alternate uses test. The expected results were for a linear trend, with the gain-framed expectation group on one end and the control group on the other. The addition of the framing manipulation was valuable as it would provide evidence of a case when placebo expectations can lead to placebo effects (gain frame) or not (loss frame).
Thus, it would offer evidence of a theoretically-derived moderating variable of placebo effects from the BPS Model framework.
H2a: Using physiological measures assessing threat and challenge responding, participants in the treatment expectation conditions would display more challenge responding than participants in the control condition.
25 H2b: Using physiological measures assessing threat and challenge responding, participants in the gain framed expectation condition would show the most physiological challenge, followed by the loss framed expectation condition, and participants in the control condition would show the least amount of challenge responding.
2.2.3 Alternate Uses Test Performance
When tasks are self-relevant, and individuals are highly engaged, differences in physiological outcomes can lead to increased performance, given the task is sufficiently sensitive to effort expenditures (Seta et al., 1992). Importantly, task performance success is not built into the model and increased performance is not a sole indicator of challenge responding. As such, task performance success can be considered a benefit of feeling challenged but not a direct indicator of physiological changes in line with coping.
Specifically, challenge evaluations encompass positive reactions which can lead to superior task performance in some situations whilst one is being monitored (Chalabaev et al., 2009). Threat reactions tend to yield negative outcomes that do not increase task performance. It is expected that, if this task is suitably sensitive to changes in effort, participants in the treatment expectation conditions should do better on the alternate uses performance test than participants in the control condition as treatment expectation participants are predicted to be more physiologically challenged.
H3a: Participants in the treatment expectation conditions would score higher on the alternate uses test than participants in the control condition.
26 2.3 Method
2.3.1 Participants and Design
One hundred and sixteen University of Toledo undergraduates were recruited from the Department of Psychology human participant pool for partial course credit in return for their participation and had usable physiological data. As can be the case with physiological data collection, some additional points of data were lost during recording for specific participants. As a result, some analyses involving physiological data have a reduced sample size. The sample includes 64 self-identified female and 52 self-identified male participants. Participants ethnically identified as 85 Caucasian, 16 African
American, 4 Asian, 1 Hispanic, 1 Native American, 6 as other, and 3 chose not to disclose. All procedures were approved in advance by the Institutional Review Board of the University of Toledo.
The Pilot Study consisted of a three level between-subjects design (control, gain framed expectation, and loss framed expectation). Physiological measures of threat and challenge were recorded throughout the participant’s experience in the lab. After receiving the treatment expectation manipulation, all participants completed an alternate uses performance test.
2.3.2 Measures and Procedure
Measures relevant to the current project are described below.
2.3.3 Health History and Demographics
At the beginning of the experiment, participants were asked to answer a series of personal health history questions (Appendix A). The questions included height and weight, use of prescription medications, and recent injury. Additional questions assessed
27 whether the participant had a cardiac illness, took cardiac or allergy medication, or any other medication that could affect alertness. Participants who circled yes for any of these questions were dismissed from the study. Standard demographic questions including date of birth, ethnicity and GPA were included on the health history questionnaire as well.
2.3.4 Cardiovascular Measures
Assessment of threat and challenge recordings required the use of an impedance cardiograph (ZKG), electrocardiograph (ECG), blood pressure monitor, non-invasive spot electrodes, and a BioPac machine. BioPac is a data acquisition and analysis system utilized for research across science domains involving living beings. As described previously, five physiological measures including HR, VC, CO, TPR, and BP were used to distinguish between threat and challenge (Blascovich et al., 2004). These five measures allowed for analysis of task engagement, challenge, and threat by using recording strategies following accepted guidelines and typical practice in the field
(Sherwood, Allen. Fahrenberg, Kelsey, Lovallo, & van Doornen 1990).
2.3.5 Mind Clearing Resource Manipulation
In the Pilot Study, perceived resources were manipulated using a bogus mind clearing expectation. Participants were assigned to one of three conditions (control, gain framed expectation, and loss framed expectation).
Participants in the gain framed expectation condition were told:
You have now completed the mental resting period. We asked you to spend this
time in a calm state like this first because mental relaxation methods such as this
have been found to enhance cognitive functioning and mental flexibility—
something that will help you on the upcoming task. This pre-task relaxation,
28 called Mind Clearing, is very effective in reducing mental distractions. While
lowering blood pressure, Mind Clearing boosts creativity, increases memory and
improves attention. Physiologically, this task actually lowers the levels of blood
lactate (reducing anxiety), boosts your energy level and increases serotonin
production (improving mood and behavior). Finally, Mind Clearing sharpens
the mind by improving focus and expands the mind through relaxation. Having
cleared your mind, given all the clear benefits of the task, will help you to do
better on the difficult cognitive task later in the study.
Whereas participants in the loss framed expectation condition were told all the previous benefits described above, the final sentenced was reframed negatively:
Having cleared your mind, given all the clear benefits of the task, will help you to
not do as poorly on the difficult cognitive task later in the study.
Participants in the control condition were only told:
You are now done with the baseline period. This was necessary to assess your
physiological readings during a resting state.
Importantly, the mind clearing resource manipulation consisted of an improvement expectation in which no benefits could be actually evoked during the 10 min period of rest. This is because the manipulation occurred after the rest period. Thus, any differences found during analysis can be considered to be placebo effects resulting from the perception of changed resources and not actual resource acquisition.
2.3.6 Alternate Uses Test
Guilford’s (1976) alternate uses test asks participants to self-generate as many possible uses for a common household object in one min (e.g. a brick, chair, and
29 newspaper). For example, a “book” can be used to read or as a door stop. Participants were prompted by the computer to begin stating alternative uses for each item for one min each. Participants listed uses aloud to not disrupt physiological recordings while typing and to increase the motivation to perform well. Listing uses aloud while the experimenter records the responses by hand provides the perception that the experimenter is judging participants. To further increase motivation to perform well, participants were told:
You will be taking part in a cognitive performance task that is currently under
development by the University of Toledo in collaboration with the University of
Toronto. The research focuses on how performance on cognitive aptitude tasks
predicts future outcomes. As such, in this experiment, you will be asked to engage
in a challenging cognitive performance task that will assess your aptitude.
Performance on this task has been found to predict key indicators of student
success at UT, including student GPA, graduation status, and starting career
salaries after graduation. For us to study this task, it is very important that you
give it your best effort.
Participants were then reminded of the mind clearing instruction information by condition and asked to begin. If participants stopped listing alternative uses, the experimenter urged participants to continue.
2.3.7 Procedure
Upon arrival, participants entered a physiological laboratory and were asked to complete an informed consent document. After participants agreed to take part in the study, they completed the standard health history questionnaire described previously
30 (Appendix A). At this point, physiological recording measures were fitted to the participants. Small surface electrodes were applied non-invasively to participant’s upper neck, lower back, right wrist, left ankle, and temples. At this point, participants were told to relax and clear their mind during an initial 10 min resting period. Blood pressure was measured twice a min using a Dinamap blood pressure monitor. After the baseline period, but before the alternate uses test, participants were randomized to one of three conditions where sham treatment expectations were manipulated (control, gain framed expectation, loss framed expectation). Participants were then taught how to complete the task.
Participants then completed the alternate uses test for 3 mins. Cardiovascular sensors would then be removed, participants were thanked for their participation and debriefed using funnel debriefing (Appendix D). Funnel debriefing is used to assess participants’ suspicion of the expectation manipulation, what they thought the study was about, and prior knowledge of the study.
2.4 Results
A set of fixed effect, omnibus, one-way ANOVA, ANCOVAs, and repeated measure ANOVA with three levels were the primary means of analysis for these data.
These ANOVAs and ANCOVAs were followed up with planned contrasts when needed to test the specific hypotheses. The planned contrasts were analyzed for a placebo response. As predicted by the BPS model, a placebo effect should be present in the treatment expectation conditions. As such, planned comparisons first tested the control condition against the treatment expectation conditions, then compared the strength of placebo response between conditions. All tests are set as two-tailed, alpha < .05.
31 2.4.1 Physiological Data Acquisition
The physiological data were examined and cleaned. BioPac software was used to conduct an Impedance Cardiography (ICG) analysis for each participant. First, a dZ-dt classifier was run. Here, the dZ-dt channel and ECG channel was selected. Next, a representative cycle was highlighted within the dZ-dt data. An entire single cycle was selected as necessary for use in template matching. A single cycle was consistently selected from the last 10 seconds of baseline recording across participants. The ICG analysis was then conducted. Within this, channels were designated for raw Z, dZ-dt, d²Z-dt², and arterial blood pressure (mean 80mmHg). From this analysis, an excel file was generated for each participant.
Data was transferred into SPSS and computed into min one through min ten of baseline, as well as, min one through three of the alternate uses test variables. Before creating these variables, cycles were excluded based on the following filter: CO ≤ 8 &
PEP ≤ .42 & LVET ≤ .42 & SV ≤ 130 & SV ≥ 20. The range 20 to 130 was used for SV, as it is the maximum range. For CO, the exercise maximum range of 36 was used as CO can be up to four times the highest normal range (i.e., 8) when exercising.
Cardiovascular reactivity of all measures was computed by subtracting the measurement taken at baseline from the measurement taken during the alternate uses.
These change scores were used in all further analyses as people vary greatly on their set point on physiological indices.
2.4.2 Analysis of Task Engagement
In testing for physiological differences in threat and challenge, participants were first assessed for evidence of task engagement. As HR and PEP are both measures of task
32 engagement, these measures were combined into a single index of task engagement by following the procedures of Seery et al. (2009). Because HR and PEP are assessing for similar cardiac responses, the measures are combined. Specifically, HR and PEP reflect the same underlying SAM versus HPA activation. To do so, HR and PEP baseline and task scores were converted into z-scores for each participant. Next, PEP scores were reverse scored so that on both measures higher scores equate to greater task engagement.
To analyze task engagement, the summary engagement score from baseline and the alternate uses test were subjected to a repeated measure ANOVA. First, it was hypothesized that participants would not display changes from one another in task engagement during the baseline recording period. This hypothesis was supported.
Specifically, as was anticipated, engagement did not differ by condition during baseline,
F(2,111) = .05, p = .951. Planned comparisons yielded no significant difference between the control and treatment expectation conditions, p = .894, 95% CI [-.475, .543], the control and gain framed expectation conditions p = .796, 95% CI [-.652, .501], nor between the control and loss framed expectation conditions p = .982, 95% CI [-.584,
.598]. The observed power was .448 for condition.
Second, it was predicted that participants would not differ from one another in task engagement during the alternate uses test. This hypothesis was supported.
Specifically, engagement did not differ by condition during the task as was anticipated,
F(2,113) = .722, p = .488. Planed comparisons yielded no significant difference between the control and treatment expectation conditions, p = .723, 95% CI [-.688, .479], control and gain framed expectation conditions p = .798, 95% CI [-.745, .574], or between the control and loss framed expectation conditions p = .390, 95% CI [-.381, .970].
33 2.4.3 Analysis of Threat and Challenge
A one-way ANCOVA was conducted to analyze markers of threat and challenge:
TPR and CO. TPR was calculated by dividing mean arterial pressure (MAP) by CO. CO was calculated by HR x SV. Cardiovascular changes in TPR, and CO distinguish between stress vulnerability and resilience. Together, a challenge response is reflected in reduced
TPR, and substantially increased CO akin to physiological and emotional confidence.
TPR and CO are combined to test for collective resilience (Mathewson et al., 2015).
Because changes in CO and TPR are both indicators of SAM versus HPA activation,
TPR and CO was converted into z-scores and summed. This created a challenge/threat index as previously used by Seery et al. (2009). Prior to summing, TPR scores were reversed scored so that TPR and CO responses share the same directionality: lower scores equal greater challenge and less threat.
To ensure that our treatment expectation manipulation post baseline can be attributed to any changes in threat/ challenge responding during the task, an ANOVA was conducted to test if there was a baseline threat/challenge difference by condition.
Importantly, the test was not significant, indicating that participants were equivalent physiologically on this measure during baseline F(2, 82) = .355, p = .702.
To analyze the threat/challenge index during the task, scores on this measure were subjected to a one-way ANCOVA and planned contrasts. First, it was predicted that there would be a significant difference by condition in the amount of challenge responding recorded. Consistent with the first hypothesis, there was a significant effect of condition on threat/challenge responding during the task after controlling for baseline threat/challenge index and alternate uses task engagement, F(2, 75) = 6.45, p = .003
34 (Figure 2). Second, it was predicted that participants in the treatment expectation conditions would display more challenge responding than participants in the control condition. Planned contrasts did not reveal support for the second hypothesis as there was not a significant difference between the control and placebo expectation conditions, p =
.677, 95% CI [-.494, .756]. Third, it was predicted that participants in the gain framed expectation condition would show the most physiological challenge, followed by the loss framed expectation condition, and participants in the control condition would show the least amount of challenge responding. The third hypothesis was partially supported.
Planned contrasts revealed a significant difference between conditions where the gain framed expectation condition did show a significant difference from the control, p = .036,
95% CI [-1.488, -.052] whereas the loss framed condition did not differ from the control p = .165, 95% CI [-.214, 1.229]. Another planned comparison yielded a significant difference between the gain framed expectation and loss framed conditions, p = .001,
95% CI [-1.992, -.564]. Means depict that the gain framed expectation condition (M = -
.617) yielded the most challenge compared to the loss framed expectation (M = .853) and control conditions (M = .044). The observed power was .06 for condition.
35 Mean Challenge Responding 1 0.8 0.6 0.4 0.2 0 -0.2 -0.4 -0.6 -0.8 Negative Treatment Control Positive Treatment Expectation Expectation
Figure 2. Pilot Study Challenge Responding by Condition.
2.4.4 Alternate Uses Test Performance
To analyze mean performance on the alternate uses, total alternative uses stated were subjected to a one-way ANOVA. It was expected that this ANOVA would yield a significant effect of condition where participants in the treatment expectation conditions would do better on the alternate uses test than participants in the control condition. The hypothesis was not supported. There was not a significant main effect of condition on the total number alternate uses stated F(2,116) = 1.028, p = .361. A planned contrast revealed that there was no difference between the control and treatment expectation conditions on the total number of uses stated, p = .807, 95% CI [-.1.807, .2.317], no significant difference between the control and positive expectation condition p = .633, 95% CI [-1.801, 2.951] or between the control and loss framed expectation condition p = .365, 95% CI [-3.447, 1.276].
The observed power was .061 for condition.
36 2.5 Discussion
The purpose of the Pilot Study was to examine the possibility that the BPS model could help account for placebo effects in performance situations. The results revealed that, as anticipated, engagement did not differ by condition during baseline and the task.
Further, participants were equivalent physiologically during baseline and thus did not differ in terms of challenge responding. Results also revealed a significant effect of condition on threat/challenge responding during the task after controlling for baseline threat/challenge index and alternate uses task engagement. Importantly, participants in the gain framed expectation condition displayed significantly more challenge responding than participants in the loss framed expectation and control conditions. Finally, there was no significant effect of performance on the alternate uses test.
As described in the introduction, one plausible explanation for this pattern of results is that the positive placebo treatment expectation is producing differences in challenge responding. That is, a positive placebo expectation is physiologically changing how participants cope with the stress of a task. More definitive evidence for such processes was tested in the Main Study (described later).
Overall, the results of this study are suggestive of the fact that the BPS model could help account for placebo effects. However, there are some notable limitations to this study. First, there was not an overarching placebo effect where participants in both the positive and loss framed conditions displayed more challenge responding. Because the loss framed expectation group did not significantly differ from the control, this suggests that there are different strength placebo effects. Although the loss framed expectation was a placebo, only the stronger positive expectation yielded a placebo
37 effect. This finding provides preliminary evidence for a placebo effect continuum as has been debated in the literature. The Main Study in this paper is designed to specifically test the placebo continuum by using placebo treatment expectations designed to push participants towards a placebo (challenge) or nocebo (threat) response.
Second, although differences in task performance were not found, prior research on the BPS model has found significant differences in challenge responding physiologically without reporting differences in task performance. Part of the benefit of combining placebo effects with the BPS model literature is that final task performance does not always have to be an indicator of successfully coping with stress. It could be that challenged participants feel better suited to cope with the stress of the task (as depicted physiologically) but the task is perceived as too difficult to yield differences. One way to address this is to manipulate the demand of the task. That is, how difficult the task is perceived to be. These issues were addressed in the Main Study (described below).
38 Chapter Three
Current Research
3.1 Overview
The current work aims to address two key points. First, a more detailed understanding of stress, where separate influences on resource and demand perceptions may lead to different threat/challenge outcomes via treatment expectations is to be examined. Placebo and nocebo effect responses to treatment administration is examined using the BPS model.
Generally, placebo expectations can be considered resources by which one has more assets to overcome situational demands—thus leading to greater feelings of success and distinct physiological markers of challenge. Specifically, it is suggested here that a placebo effect is most likely to be found when individuals are more effectively able to cope (challenge) because the perception of resources are high and situational demands are low. On the other hand, nocebos can be considered a situation where people perceptually have resources, but the demand of the situation is too high, resulting in distinct physiological markers of threat. Nocebo effects thus may be most likely to be captured when individuals are less effectively able to cope (threat) because the perception of resources are low and situational demands are high. Challenge and threat concepts of the
BPS model thus influence placebo effect and nocebo manifestations.
Second, the current work also aims to address the variation in placebo responses, and speak to relevant, unanswered questions of resource and demand equivalence within the BPS model literature. This unexplored interplay of high and low resources and situational demand equivalence (high resources and high demands or low resources and
39 low demands) may result in different threat and challenge coping patterns than standard
BPS model predictions where resources and situational demands are unequal.
In the present study, there was a 2 (Resource: high or low) x 2 (Demand: high or low) between-subjects design. This set up allows for the two aims of this paper to be addressed. Importantly, message framing is no longer used as a manipulation as a different placebo expectation was used in order to capture placebo and nocebo effects.
3.2 Main Hypotheses
3.2.1 Task Engagement
Task Engagement predictions mirror the predictions and findings described in the
Pilot Study. First, increased engagement and investment signal motivation toward goal attainment when faced with various situational demands. When positive performance is desired, physiologically, the body becomes more engaged. Changes in engagement can be directly attributed to changes in stressful stimuli (e.g. treatment expectations) and are predicted therefore to not be present during physiological recordings prior to treatment at baseline. Second, it was expected that all participants would be equally engaged during the alternate uses test. No condition main effect or interaction was anticipated, as all groups were expected to display task engagement.
H1a: Using physiological measures assessing task engagement, participants would not display changes in task engagement during the baseline recording period.
H1b: Using physiological measures assessing task engagement, participants would not differ from one another in task engagement during the alternate uses test.
40 3.2.2 High Resource and Low Demand
It is theorized here that in placebo paradigms, the administration of the placebo manipulation is akin to providing an individual a resource to cope with a stressor. That is, the expectation of a treatment (placebo or active) can be conceptualized as a resource that allows one to make a challenge rather than a threat evaluation. If these results were found, it would provide preliminary evidence that placebo effects in performance situations can be the result of differences in challenge and threat evaluations. Although exploratory, both low resources and low demand condition is thought to manifest in the midpoint of the nocebo-threat/placebo-challenge continuum. This condition is being used as the control condition as the comparison for the following predictions assessing for more or less challenge.
A more challenged individual is predicted by the BPS model to cope more effectively with situational pressures and display physiological responses in line with better coping. The BPS model predicts that effective coping, or challenge, is marked by high resources and low demand. That is, resources such as skills or expectations drive an individual to be prepared. As such, the situation is not as demanding when one has tools to succeed. Given these BPS model predictions and treatment expectations within the placebo literature, a high resource and low demand condition predicts clearly a placebo- challenge response along the nocebo-threat/placebo-challenge continuum.
H2a: Using physiological measures assessing threat and challenge, participants in the high resource and low demand condition would display the greatest amount of challenge responding akin to a placebo response.
41 3.2.3 Low Resource and High Demand
A more threatened individual is predicted by the BPS model to cope less effectively with situational pressures and display physiological responses in line with poorer coping. The BPS model predicts that ineffective coping, or threat is marked by low resources and high demand. That is, resources such as skills or expectations are not enough to prepare an individual. As such, the situation can be overwhelming and demanding when one does not have the tools to succeed. Perceiving that a treatment may be taxing through increasing demand (e.g., Once the test starts you will have ONLY 3 minutes to complete the test items) provides the perception of threat. As such, a low resource and high demand condition is predicted to exhibit less of a placebo-challenge response and more of a nocebo-threat pattern.
H2b: Using physiological measures assessing threat and challenge, participants in the low resource and high demand condition would display the greatest amount of threat responding akin to a nocebo response.
3.2.4 High Resource and High Demand
The current study aims to also disentangle the relationship between resources and demands when they are equal. That is when participants have both high (or low) resources and demands simultaneously. Past research addresses non-equivalent resources and demands but fails to recognize that the coping stress relationship may not always be that straightforward. Using a placebo paradigm, the present study orthogonally manipulates resources and demands to test an unconsidered, and more realistic, application of BPS predictions.
Following the logic of the BPS model where a challenge response occurs when
42 resources are perceived as exceeding situational demands, it is inferred that exploration of both high resources and high demand can be tentatively predicted to show more placebo-challenge than low resources and low demand, but not as much challenge as the standard BPS model predictions (high resources, low demand). Inclusion of the high resource and high demand condition addresses an unanswered question within the BPS model literature and adds to the placebo effect literature by helping to explain in what conditions more of a placebo or nocebo effect will occur.
H2c: Using physiological measures assessing threat and challenge, participants in the high resource and high demand condition can be tentatively predicted to show more challenge than low resources and low demand, but not as much as the standard challenge pattern (high resources, low demand) akin to a placebo response.
3.3 Alternate Uses Test
When tasks are self-relevant, and individuals are highly engaged, differences in physiological outcomes can lead to increased performance. To reiterate, task performance success is not built into the model and increased performance is not a sole indicator of challenge responding. As such, task performance success can be considered a benefit of feeling challenged but not a direct indicator of physiological changes in line with coping.
Threat reactions tend to yield negative outcomes that do not increase task performance. It is expected that participants expected to be challenged (high resource/low demand and high resource/high demand) should do better on the alternate uses performance test than participants expected to be threatened (low resources/high demand) or neutral (low resources/low demand).
43 H3a: Participants in the high resource/low demand condition should score highest on the alternate uses performance test, followed by the high resource/high demand condition, then participants in the low resources/high demand condition, and participants in the low resources/low demand condition should score the lowest.
3.4 Method
3.4.1 Participants and Design
Two hundred forty-eight (112 male, 136 female) University of Toledo undergraduate students 16 years of age or older were recruited from the Department of
Psychology human participant pool. Four participants were under the age of 18. After filtering for whether there were equipment malfunctions during data collection we were left with a final sample size of 165 (80 male, 85 female) for data analysis. Participants ranged in age from 16 to 30. One hundred twenty-eight were White, 31 were African
American, 5 were Hispanic, and 1 declined to answer. All procedures were approved in advance by the Institutional Review Board of the University of Toledo. All participants received partial course credit in return for their participation.
The present study consists of a 2 (Resource: high or low) x 2 (Demand: high or low) between-subjects design. Physiological measures of threat and challenge were recorded throughout the participant’s experience in the lab. After receiving the resource/ demand manipulation, all participants completed a stressful word test.
3.4.2 Materials and Measures
3.4.2.1 Health History Questionnaire and Demographics
At the beginning of the experiment, participants were asked to answer a series of personal health history questions (Appendix A). The questions are similar to those
44 described in the Pilot Study. In the Main Study, gender was changed to biological sex on the health history questionnaire. The question, “have you ever been diagnosed with dermatitis” was also added to screen for whether participants may have an allergic reaction to the temple electrode gel. No students indicated that they have or have had dermatitis. Students who indicated that they have a cardiac illness, take blood pressure medication, drank caffeine or exercised within four hours were not included in the study.
All measures used are identical to the Pilot Study except a tDCS resource and placebo demand manipulations are added.
3.4.2.2 Cardiovascular Measures
The cardiovascular measures used mirror those described in the Pilot Study.
3.4.2.3 Alternate Uses Test
The alternate uses test measure is the same as the test described in the Pilot Study with the addition of three more words “button, barrel, and chair”. These words were added to increase the demand of the task. In the Main Study, participants had 30 seconds to state as many alternate uses as possible per word, whereas in the Pilot Study, participants had 1 min per word. The total time participants had to complete the alternate uses test was maintained in the Main Study (3 min).
3.4.2.4 tDCS Resource Manipulation
All participants experienced sham tDCS (Caplandies et al., 2017). Although tDCS is an actual medical procedure, our version of tDCS did not involve actual stimulation.
Rather, electrodes on participant’s temples in the procedure were paired with white noise to enhance the idea that something is happening. tDCS expectations were used as a resource manipulation in this study as a means to convince participants that their
45 experience in the lab involves a stimulation know to alter performance. To further enhance the effectiveness of the resource manipulation, the experimenter applied, using a syringe made for gel application, a drop of tea tree shampoo to participant’s temple electrodes. The shampoo was concealed in a plain shampoo travel bottle labeled “Temple
Electrodes.”
High-resource was manipulated by telling participants
In this study, we are studying the effects of a non-invasive brain stimulation
technique that applies a mild direct electrical current via the scalp to enhance or
diminish neuronal excitability called transcranial direct current stimulation. We
are looking at an experimental procedure to examine the effects of direct current
stimulation on different types of cognitive performance that you will be exposed
to later in the study. During the past 10 minutes you just experienced the direct
current stimulation procedure. In order to achieve accurate temple electrode
readings during this non-invasive procedure, I had to apply a gel to your temple
electrodes. The gel was harmless and had a menthol smell to it. Some participants
have reported a slight tingling sensation. Previous research has found transcranial
direct current stimulation to enhance cognitive stimulation and mental flexibility.
Benefits of enhanced cognitive stimulation include reducing mental distractions,
lowering blood pressure, boosting creativity, increasing memory and improving
attention. Physiologically, this task actually lowers the levels of blood
lactate (reducing anxiety), boosts your energy level and increases serotonin
production (improving mood and behavior). Finally, transcranial direct current
stimulation has been found to sharpen the mind by improving focus and
46 expanding the mind. Transcranial direct current stimulation, given all the clear
benefits, will help you to do better on the cognitive test later in the study.
Low-resource participants were told
In this study, we are studying the effects of a non-invasive brain stimulation
technique called transcranial direct current stimulation. We are looking at an
experimental procedure to examine the effects of direct current stimulation on
different types of cognitive performance that you will be exposed to later in the
study. During the past 10 minutes you just experienced the direct current
stimulation procedure. In order to achieve accurate temple electrode readings, I
had to apply a gel to your temple electrodes. This gel was part of standard
physiological temple recordings. The gel was harmless and has a menthol smell to
it. Some participants have reported a slight tingling sensation.
3.4.2.5 Placebo Demand Manipulation
High and low situational demand was manipulated. Although all participants completed the same word test described previously, perceived difficulty of the test differed by condition. As such, participants in the high demand condition were told
Today you will be competing against other participants for a $25 gift card.
Specifically, participants will be entered into a raffle based on how many total
alternate uses stated. For every 5 alternate uses you will earn one raffle ticket. The
better you perform, the more chances you will have to win the gift card. In this
study, participants are allowed to complete all the test items in 3, 4, 5, or 6
minutes. You have been randomly assigned to complete all the test items in only 3
minutes. This means it will be more difficult for you to earn a lot of entries for the
47 drawing. Once the test starts you will have ONLY 3 minutes to complete the test
items and earn your entries into the raffle.
Low demand participants were told
Today you will be competing against other participants for a $25 gift card.
Specifically, participants will be entered into a raffle based on how many total
alternate uses stated. For every 5 alternate uses you will earn one raffle ticket. The
better you perform, the more chances you will have to win the gift card. In this
study, participants are allowed to complete all the test items in 1, 2, or 3 minutes.
You have been randomly assigned to complete all the test items in 3 minutes. This
means it will be easier for you to earn a lot of entries for the drawing. Once the
test starts, you will have 3 minutes to complete all the test items and earn your
entries into the raffle.
3.4.2.6 Supplementary Questions
Participants were asked to complete a series of dependent measures after the alternate uses test in order to supplement physiological and performance measures. These items include how demanding participants found the test to be, as well as, perceived difficulty, performance, resources to successfully perform the test, and if the participants treated the test as a challenge to overcome (Appendix C). These items are included as self-report measures to assess perceived threat and challenge.
3.4.2.7 Manipulation Check Item
To assess the effectiveness of the experimental resource manipulation and an expectation manipulation check to assess whether participants expected tDCS to enhance performance, the following question was asked: “At the beginning of the experiment, the
48 experimenter may have explained to you the purpose of transcranial direct current stimulation. Please verify if you were told the purpose of this stimulation by selecting the reason you remember from the options listed below:” (Appendix C). Participants were able to select between three options. High-resource participants should have selected the answer that the experimenter explained the tDCS was used “to enhance cognitive stimulation and do better on the word test.” Participants in the low-resource condition should have selected the answer that tDCS was used “as part of standard physiological recordings”. The third option presented was “the experimenter did not provide me with any explanation.”
3.4.3 Procedure
Upon arrival, participants entered a physiological laboratory and were asked to complete an informed consent document (Appendix E). This form states that the study involves a laboratory stressor task. The consent form also indicates that participants can discontinue their participation in the study at any time. After participants agreed to take part in the study, they completed the standard health history questionnaire described previously (Appendix A). At this point, physiological recording measures were fitted to the participants. Small surface electrodes were applied non-invasively to participant’s upper neck, lower back, right wrist, left ankle, and temples. The placebo temple gel was explained and applied to participant’s temple electrodes. At this point, participants were told they are receiving tDCS. Blood pressure was measured twice a min using a Dinamap blood pressure monitor.
Participants then rested during an initial 10 min baseline/sham tDCS period as per standard practice in the field. After the baseline period, participants were informed of the
49 purpose of the temple gel (resource manipulation). Participants would then be taught how to complete the alternate uses test and were informed of the test’s difficulty (demand manipulation). Participants then completed the alternate uses test for 180 seconds.
Afterwards, participants sat for a 5 min recovery period. Finally, participants answer questions about the alternate uses test and answered the manipulation check item
(Appendix C). Cardiovascular sensors were removed, participants were thanked for their participation and debriefed using funnel debriefing (Appendix D). Funnel debriefing was used to assess participants’ suspicion of the expectation manipulation, what they thought the study was about, and prior knowledge of the study.
50 Chapter Four
Results
4.1 Overview
An initial inspection of descriptive statistics was conducted. Next, two sets of correlations, one for all task engagement measures and another for all threat/challenge measures were conducted. Then, following the analyses described in the Pilot Study, a set of fixed effect, omnibus, 2x2 ANOVA, ANCOVAs, and a 2x2 repeated measure
ANOVA were employed as the primary means of analysis for the data. The ANOVAs and ANCOVAs were followed up with planned contrasts when needed to test the specific hypotheses. The first planned contrasts refers to H2a and was designed to test for a challenge response by comparing the low resource/low demand condition to the high resource/low demand condition. To test H2b, a second planned contrast examined how the low resource/low demand condition compares to the low resource/high demand condition. The third planned contrast, concerning H2c, tests to see if the high resource/high demand condition is showing more challenge than the low resource/low demand condition. The fourth contrast, also concerning H2c, tests to see if the high resource/high demand condition differs from the high resource/low demand condition All tests were set as two-tailed, alpha < .05.
4.2 Manipulation Check Analysis
A chi-square test of independence was conducted on the manipulation check question. A variable was created to test whether participants answered the manipulation question correct or not as based on condition where 0 was coded as incorrect and 1 as correct. The outcome of the chi- square test of independence revealed that answering the
51 manipulation check question correctly was significantly related to condition X² (3, N =
164) = 18.286, p < .001. Of the 41 participants in the low resource/ low demand condition, 22 (53.66%) answered the manipulation check question correctly; of the 40 participants in the high resource/ high demand condition, 36 (90%) answered the manipulation check question correctly; of the 45 participants in the low resource/high demand condition, 25 (55.55%) answered the manipulation check question correctly and
30 (78.95 %) of 38 participants answered the manipulation check question correctly in the high resource/ low demand condition. For percentages, see Table 1. Most excluded participants answered the manipulation check question correctly as well, X² (3, N = 78) =
10.540, p = .014.
These data indicate that there were unanticipated condition differences on the manipulation check, with participants in the low resource conditions answering incorrectly more than participants in the high resource conditions. Of those in the low resource conditions, 44.19% incorrectly selected that the purpose was to enhance cognitive stimulation and do better on the word test or that the experimenter did not provide any explanation. Comparatively, only 12.24 % of the high resource conditions incorrectly answered that the purpose was part of normal physiological recording or that the experimenter did not provide any explanation. This was surprising, as participants in all three conditions were expected to answer the manipulation check correctly.
52 Table 1. Manipulation Check Question by Experimental Condition.
Condition Low Low High High Resource/High Resource/Low Resource/High Resource/Low Demand Demand Demand Demand
Count Incorrect 20 19 4 8
Correct 25 22 36 30
% Within Condition Incorrect 44.44% 46.34% 10% 21.05%
Correct 55.56% 53.66% 90% 78.95%
Table 1: Percent and count of whether or not participants answered the following resource manipulation check question correctly: “At the beginning of the experiment, the experimenter may have explained to you the purpose of transcranial direct current stimulation. Please verify if you were told the purpose of this stimulation by selecting the reason you remember from the options listed below.”
4.3 Physiological Data Acquisition
The following procedures are identical to those described in the Pilot Study. Next, the physiological data were examined. BioPac software was used to conduct an
Impedance Cardiography analysis for each participant. First, a dZ-dt classifier was run.
Here, the dZ-dt channel and ECG channel was selected. Next, a representative cycle is highlighted within the dZ-dt data. An entire single cycle was selected as necessary for use in template matching. A single cycle was consistently selected from the last 10 seconds of baseline recording across participants. The ICG analysis was then conducted. Within this, channels were designated for raw Z, dZ-dt, d²Z-dt², and arterial blood pressure
(mean 80mmHg). From this analysis, an excel file was generated for each participant.
53 Data was then transferred into SPSS and computed into min one through min ten of baseline, as well as, min one through three of the word test variables and min one through five of recovery. Before creating these variables, cycles were excluded based on the following filter: CO ≤ 8 & PEP ≤ .42 & LVET ≤ .42 & SV ≤ 130 & SV ≥ 20. The range 20 to 130 was used for SV, as it is the maximum range. For CO, the exercise maximum range of 36 was used as CO can be up to four times the highest normal range
(i.e., 8) when exercising.
Cardiovascular reactivity of all measures were computed by subtracting the measurement taken at baseline from the measurement taken during the alternate uses.
These change scores were used in all further analyses as people vary greatly on their set point on physiological indices.
4.3.1 Analysis of Task Engagement
In testing for physiological differences in threat and challenge, participants were first assessed for evidence of task engagement using the analytic strategy described in the
Pilot Study. As HR and PEP are both measures of task engagement, these measures were combined into a single index of task engagement by following the procedures of Seery et al. (2009). To do so, HR and PEP baseline and task scores were converted into z-scores for each participant. Next, PEP scores were reverse scored so that on both measures higher scores equate to greater task engagement. PEP and HR are combined because they are capturing similar cardiac responses. To justify the use of this combined measure, correlations between baseline and task overall engagement scores, PEP and HR was conducted (see Table 2). There was a significant correlation at the .01 level between baseline engagement and baseline PEP, baseline engagement and baseline HR, alternate
54 uses task engagement and alternate uses PEP, as well as task engagement and alternate uses HR. This suggests PEP and HR scores are associated like we would expect.
Table 2. Task Engagement Correlations.
Baseline ALT Task Task Baseline Baseline Engagemen ALT PEP ALT HR Engage PEP HR t ment Baseline Task Pearson .705 .671 1 .040 .096 -.015 Engagement Correlation ** ** Sig. .612 .000 .220 .000 .845 N 165 165 165 165 165 165 ALT Task Pearson .552 .837 1 .040 .015 Engagement Correlation ** ** Sig. .614 .000 .852 .000 N 165 165 165 165 165 Baseline PEP Pearson 1 .067 -.053 .004 Correlation Sig. .396 .498 .951 N 165 165 165 165 ALT PEP Pearson 1 .066 .005 Correlation Sig. .403 .951 N 165 165 165 Baseline HR Pearson 1 -.026 Correlation Sig. .745 N 165 165 ALT HR Pearson 1 Correlation Sig. N 165 Table 2: Correlations between baseline task engagement and baseline PEP, baseline task engagement and baseline HR, alternate uses task engagement and alternate uses PEP, as well as task engagement and alternate uses HR.
To analyze task engagement, the summary engagement score from baseline and the alternate uses test were subjected to a between subjects repeated measure 2 Resource
(high or low) by 2 Demand (high or low) ANCOVA with height and weight used as covariates. It was expected that no significant effect of resource or demand would be found as all participants are expected to not display changes in task engagement during the baseline recording period. It was also expected that participants would not display
55 changes in task engagement during the alternate uses test. These hypotheses were supported. Engagement did not increase from baseline during the alternate uses test as was anticipated, Fs < 2.405, ps > .123 (see Figure 3). A post-hoc power analysis was conducted for resource (.136), demand (.058), and the interaction between resource and demand (.110). For task engagement, when controlling for participant sex, height and weight, there is still no significant effect of resource or demand Fs > 2.459, ps > .119.
Task Engagement 0.3
0.2
0.1
0
-0.1
-0.2
Levels of Task Engagement Task of Levels -0.3 Low Resource Low Resource High Resource High Resource High Demand Low Demand High Demand Low Demand
Condition
Figure 3. Task Engagement by Experimental Condition.
To follow-up on these analyses that used the combined HR and PEP dependent variable, we also analyzed HR and PEP independently. When analyzed separately, HR,
Fs < 2.220, ps > .140 and PEP, Fs < 1.765, ps > .186, yielded the same results as the combined engagement variable. For means, see Table 2.
56 Table 3. Mean Task Engagement for HR, PEP, and Combined.
HR PEP Combined M SD M SD M SD
Baseline
Low Resource High Demand -.062 .991 -.085 .347 .022 1.044
Low Demand .140 1.117 .060 .311 .201 1.117
High Resource High Demand .024 1.095 -.290 1.95 -.2197 1.724
Low Demand -.092 .835 -.082 .838 -.174 1.057
Alternate Uses Test
Low Resource High Demand .242 2.098 .096 .334 -.201 1.262
Low Demand -.071 .000 .045 .390 .302 2.148
High Resource High Demand -.071 .000 .063 .399 -.015 .398
Low Demand -.071 .000 -.204 1.311 -.027 .390
Table 3: Mean Task engagement by Condition for HR, PEP, and the Combined measure.
4.3.2 Analysis of Threat and Challenge
A one-way ANCOVA was conducted to analyze markers of threat and challenge:
TPR and CO. TPR was calculated by dividing mean arterial pressure (MAP) by CO. CO was calculated by HR x SV. Because changes in CO and TPR are both indicators of SAM versus HPA activation, TPR and CO was converted into z-scores and summed. This created a challenge/threat index as previously used by Seery et al. (2009). Prior to summing, CO scores were reversed scored so that TPR and CO responses share the same directionality: higher scores equal greater challenge and less threat. CO and TPR are combined because they are capturing similar cardiac responses. To justify the use of this
57 combined measure, a correlation between alternate uses task engagement, alternate uses threat/challenge responding, alternate uses CO, alternate uses TPR, was conducted (see
Table 4). There was a significant correlation at the .01 level for challenge responding with CO and TPR. Further, CO and TPR were correlated. These results indicate that CO and TPR scores are associated like we would expect.
Table 4. Correlations between Alternative Uses Task Period Measures.
ALT ALT Task Threat/Challe ALT CO ALT TPR Engagement nge Pearson 1 -.024 -.060 .013 ALT Task Correlation Engagement Sig. .758 .441 .864 N 165 165 165 165 Pearson .967 .967 1 ALT Correlation ** ** Threat/Challenge Sig. .000 .000 N 165 165 165 Pearson .870 1 Correlation ** ALT CO Sig. .000 N 165 165 Pearson 1 Correlation ALT TPR Sig. N 165 Table 4: Correlations between alternate uses task engagement, alternate uses threat/challenge responding, alternate uses CO, alternate uses TPR, **Correlation is significant at the 0.01 level (2-tailed). To ensure that the manipulations post baseline can be attributed to any changes in threat/challenge responding during the task, an ANCOVA was conducted to test if there was a baseline threat/challenge difference by resource or demand manipulations. It was predicted that this analysis would not be significant as participants are predicted to not display changes in threat/challenge during the baseline recording period. There was no significant effect of condition on threat/challenge responding at baseline F (3,161) =
.359, p = .783.
58 To analyze the threat/challenge index during the task, scores on this measure were subjected to a 2 Resource (high or low) x 2 Demand (high or low) ANCOVA and planned contrasts with height in inches and weight as covariates. Planned contrasts were expected to reveal a significant difference between resource and demand manipulations.
First, it was predicted that participants in the high resource and low demand condition would display the greatest amount of challenge responding akin to a placebo response.
Second, it was expected that participants in the low resource and high demand condition would display the greatest amount of threat responding akin to a nocebo response. Third, participants in the high resource and high demand condition can be tentatively predicted to show more challenge than low resources and low demand, but not as much as the standard challenge pattern (high resources, low demand) akin to a placebo response.
Finally, participants in the low resource and low demand condition were predicted to display neither a challenge nor a threat response and fall in the middle of the placebo/nocebo continuum.
Inconsistent with the hypothesis, there was no significant effect of resource, demand, or the interaction between resource and demand on threat/challenge responding after controlling for height in inches, weight and baseline engagement, Fs <.345, ps >
.558 (Figure 4). Four planned contrasts to test H2a, H2b, and H2c were conducted. These tests revealed no significant differences between conditions, ps > .116. Specifically, there was no significant effect of a placebo response for H2a between the low resource/low demand and high resource/ low demand conditions. There was no significant finding for a nocebo response for H2b when contrasting low resource/low demand and low resource/ high demand conditions. Third, the contrast to test if the high resource/high demand
59 condition showed more challenge than the low resource/low demand condition did not support the hypothesis. Finally, there was no significant effect of challenge responding between the high resource/high demand and high resource/low demand conditions.
Although not significant, means depict that the conditions lined up with predictions.
Specifically, the low resource/ high demand condition had the lowest challenge response
(M = -.116), followed by the low resource/ low demand condition (M = .005), the high resource/ high demand condition (M = .020), and the high resource/low demand condition yielded the most challenge responding (M = .032). A post-hoc power analysis was conducted for resource (.054), demand (.090), and the interaction between resource and demand (.055).
Challenge Responding by Condition
0.25 0.2 0.15 0.1 0.05 0 -0.05 -0.1
Challenge Responding Challenge -0.15 -0.2 Low Resource Low Resource High Resource High Resource -0.25 High Demand Low Demand High Demand Low Demand
Condition
Figure 4. Challenge Responding as Depicted by Condition.
To follow-up on the threat/challenge analyses that used the combined CO and
TPR dependent variable, we also analyzed CO and TPR independently. When analyzed
60 separately, CO, Fs < .132, ps > .717 and TPR, Fs < .527, ps > .469 were not significant.
Degrees of freedom for these analyses are 1, 157. For means, see Table 5. For CO and
TPR, no significant planned contrasts were found.
Table 5. Mean Threat/Challenge for TPR, CO and Combined.
TPR CO Combined
M SD M SD M SD
Low Resource
High Demand -.073 .926 -.043 1.055 -.116 1.912
Low Demand -.033 .940 .038 .884 .005 1.784
High Resource
High Demand .013 1.028 .007 1.036 .020 1.975
Low Demand .004 1.008 .027 .884 .032 1.843 Table 5: Mean Threat/Challenge for TPR, CO and Combined.
4.4 Alternate Uses Test Performance
To analyze mean performance on the alternate uses, total number of alternate uses stated (fluency) were subjected to a 2 Resource (high or low) x 2 Demand (high or low) one-way ANOVA. It was expected that this ANOVA would depict a significant effect of condition where participants in the high resource/low demand and high resource/high demand conditions should do better on the alternate uses performance test than participants in the low resources/high demand or low resources/low demand conditions.
This hypothesis was not supported. There was no significant main effect of resource or demand on the number of alternate use words stated, Fs < 2.089, ps > .150 (Figure 5).
Planned comparisons indicated that there was no significant difference across conditions ps >.15. Three additional ANOVAs were conducted for originality, flexibility, and elaboration of alternate uses stated following the procedures outlined by the tests creator,
61 J.P Gilford (1967). Originality was coded as 0, 1 or 2, where 0 was common, 1 for responses were stated less than 5 times total, and 2 for responses that were only stated once. Originality was not significant originality Fs < .160, ps > .690. Flexibility, the total number of categories participants responses fell under was not significant Fs < 2.78, ps >
.097. For example, categories for the word brick for one participant were coded as
“weight, to stop, weapon, and material.” Elaboration was coded for the amount of detail.
For example, "a brick" was coded as 0 whereas "a door stop to prevent a door slamming shut in a strong wind" was coded as 2 with one point awarded for explanation of door slamming, and a second awarded for further detail about the wind. The elaboration
ANOVA was not significant Fs < 3.444, ps > .065. A post-hoc power analysis was conducted for resource (.069), demand (.301), and the interaction between resource and demand (.142).
Alternate Uses Test 30 28 26 24
Uses Stated Uses 22 20 Num ber of Alternate ber Num of Low Resources Low Resources High Resources High Resources High Demand Low Demand High Demand Low Demand Condition
Figure 5. Number of Alternate Uses Stated by Condition (Fluency).
62 Table 6. Mean Alternate Uses Test Performance.
Fluency Originality Elaboration Flexibility M SD M SD M SD M SD Low
Resource High Demand 27.535 6.727 6.070 4.818 .976 1.506 23.419 5.758
Low Demand 25.091 5.964 5.568 3.355 .568 1.129 21.568 4.474
High
Resource High 26.180 6.464 5.846 4.252 1.053 2.013 22.615 5.720 Demand Low Demand 25.590 7.738 5.769 5.760 .615 .990 21.615 5.941
Table 6: Mean Alternate Uses Test Performance for Fluency, Originality, Elaboration, Flexibility. On all measures, higher scores equate to better performance.
4.5 Analysis of Supplementary Questions
At the end of the study, all participants were asked to complete a set of supplementary questions concerning participants experience and perception of tDCS and the word task. Other questions included the State Self Esteem, Perceived Stress, and the
General Self-Efficacy scales (Heatherton & Polivy, 1991; Cohen, Kamarck, &
Mermelstein, 1983; Schwarzer & Jerusalem, 1995). For exploratory purposes, all supplementary questions were submitted to separate 2 Resource x 2 Demand ANOVAs.
First, when analyzing supplementary questions concerning participants experience and perception, there was a significant main effect of demand for whether tDCS made participants feel anxious F (1,161) = 4.134, p = .044. Specifically, those in the low demand conditions were more anxious than those in the high demand conditions. This result is surprising and does not lend support to the effectiveness of the demand manipulation. For means, see Table 7.
63 Second, the overall State Self-Esteem Scale was not significant (Fs < 2.691, ps >
.130), however there was a significant interaction between resource and demand for the
Performance State Self-Esteem subscale F (1,161) = 4.776, p = .030. To clarify this interaction, the four main contrasts from the threat/challenge analyses were conducted as follow-up tests. Because the present analyses were exploratory, a Bonferroni-Holms post- test correction was performed (Holmes, 1979). None of the follow-up tests were significant. For means, see Table 8.
No other supplementary questions were significant and are not discussed here.
Table 7. Mean Ratings of Whether Participants Were Anxious during tDCS. Condition Mean Standard Deviation Low Resource/High 2.256 1.311 Demand Low Resource/Low 3.159 1.569 Demand High Resource/High 2.846 1.548 Demand High Resource/Low 2.949 1.891 Demand Table 7: Mean ratings of whether participants were made to feel anxious by the tDCS. On a scale from 1 extremely anxious to 7 not at all anxious.
64 Table 8. Mean Ratings of Performance State Self-Esteem. Condition Mean Standard Deviation Low Resource/High 27.465 4.626 Demand Low Resource/Low 26.659 4.580 Demand High Resource/High 25.846 4.945 Demand High Resource/Low 28.180 4.248 Demand Table 8: Mean ratings of Performance State Self Esteem on a scale from 7 to 35.
4.5.1 Individual Differences
The Ten-Item Personality Measure was administered to participants and the items were recoded into five subscales using the scoring process outlined by a scoring guide
(Gosling, Rentfrow, & Swann, 2003): Agreeableness, Extraversion, Conscientiousness,
Emotional Stability, and Openness to Experience. For the overall physiological measure of threat/challenge during the alternate uses test, resource, demand and each of the Ten-
Item Personality subscales variables were submitted to separate hierarchical logistic regression analyses. In these regression analyses, the resource manipulation and demand manipulation were included as predictors on the first step of the model and the second step included the interaction between resource and demand. For each regression, for example, agreeableness was also included in the first step. The second step included the interaction between agreeableness and resource, and the interaction between agreeableness and demand. The third step included the interaction between resource, demand and agreeableness. The structure of this regression was repeated for each of the
Ten-Item Personality subscales.
65 For agreeableness, in the final step of the model, there were no significant effects (ps
> .061). The next regression assessed extraversion. For extraversion, the final saturated model yielded no significant effects (ps > .164). For conscientiousness, step three produced a significant effect of conscientiousness b= -.367, t(155) = -2.28, p = .024
(Table 9). For every one point increase in challenge responding, there is a .367 decrease in conscientiousness. These findings suggest that participants who are less conscientious become more challenged during the word task. In the fourth regression for the emotional stability subscale, step three did not yield any significant effects (ps > .428). Finally, openness to experience produced a significant effect of resource b= -1.497, t(156) = -
3.002, p = .003, openness to experience b = -.331, t(156) = -2.551, p = .012, and the interaction between resource and openness to experience b= 1.527, t(156) = 3.080, p =
.002 (Table 10). For every one point increase the challenge responding during the word task, there is a 1.497 decrease in resource, a .331 decrease in openness to experience, and a 1.527 increase in the interaction between resource and openness to experience.
Challenge responding increase for participants given a low resource who were less open to experience. For those in the high resource conditions, challenge responding increased if participants were more open to experience.
66 Table 9. Ten Item Personality Measure Conscientiousness.
Step 1 Step 2 Step 3
B SE B Β B SE B β B SE B β
Resource .114 .292 .031 -1.371 1.367 -.368 -2.485 1.925 -.668
Demand -.094 .292 -.025 -1.579 1.361 -.425 -2.601 1.844 -.700
Conscientiousness -.457 -.559 -.203 .120 -.133 .211 -.300 .245 -.367 * *
Resource x Demand .228 .588 .052 2.361 2.659 .542
Resource x Conscientiousness .251 .241 .379 .457 .348 .690
Demand x Conscientiousness .252 .241 .380 .442 .334 .666
Resource x Demand x Conscientiousness -.397 .483 -.509
R2 .019 .033 .037
Table 9: Regression coefficients for the Ten Item Personality Measure Conscientiousness and the alternate uses period challenge responding. * Significant at the 0.05 level.
67 Table 10. Ten Item Personality Measure Openness to Experience.
Step 1 Step 2 Step 3
B SE B Β B SE B β B SE B β
Resource .061 .292 .016 -3.594 1.444 -.967 -5.565 1.854 -1.497 * * Demand -.115 .291 -.031 1.684 1.472 .454 -.759 2.063 -.205 Openness to Experience -.226 .133 -.134 -.410 .202 -.243 -.560 .219 -.331 * * Resource x Demand .131 .577 .030 4.795 2.833 1.100 Resource x Openness to Experience .697 .268 .987 1.078 .350 1.527 * * Demand x Openness to Experience -.359 .272 -.511 .109 .388 .155
Resource x Demand x Openness to Experience -.909 .540 -1.068
R2 .019 .063 .080
Table 10: Regression coefficients for the Ten Item Personality Measure Openness to Experience and the alternate uses period challenge responding. * Significant at the 0.05 level.
68
Openness to Experience Figure 6. Challenge Responding by Openness to Experience.
4.5.2 Excluded Participants
To verify that there were no differences in participants that were excluded from the main analyses, all analyses were conducted on the full sample (N = 248). Because some excluded participants were removed duo to missing physiological readings, the following analyses have a reduced sample size. Results revealed task engagement was not significant for the excluded participants, Fs < 2.758, ps > .099. Challenge responding was also not significant for excluded participants when controlling for height and weight, and baseline challenge responding, Fs < .137, ps > .712. Further, no significant difference was found for number of alternate uses stated Fs < 1.290, ps > .257. These results echo those of the Main Study. For all other analyses, there were no outstanding differences from the results previously reported.
69 Chapter Five
Discussion
5.1 Overview
This research aimed to examine whether the Biopsychosocial Model (BPS) of Threat and Challenge helps explain the occurrence of placebo effects by combining the literature on stress and coping with that of placebo effects. Upon arrival, participants entered a physiological laboratory, completed an informed consent and a standard health history questionnaire. Participants were then fitted with physiological recording measures and the placebo temple gel was explained and applied to participant’s temple electrodes. At this point, participants were told they are receiving tDCS and rested for an initial 10 min baseline/sham tDCS period. After the baseline period, participants were provided different information regarding the purpose of tDCS and the temple gel (resource manipulation). Participants were then taught how to complete the alternate uses test and were provided different information relating to the test’s difficulty (demand manipulation). Participants completed the alternate uses test for 180 seconds then sat for a 5 min recovery period. Inconsistent with the BPS model, during the alternate uses test there were no effects of either the demand or resource manipulations on the primary dependent variables of threat/challenge. Although these findings are discouraging, the results of task engagement and the mean trend for challenge responding did line up with hypotheses. Below, the findings are reviewed in greater detail through a discussion of mediation, moderation, the BPS Model and placebo effects, a real-world application of the BPS Model, an examination of the BPS Model as continuous or discrete, and other factors.
70 5.2 Manipulation Check Data
Participants were asked to verify the purpose of the tDCS to assess the effectiveness of the resource manipulation. Question options included “to enhance cognitive ability and do better on the test” (high resource), “as part of normal physiological recording” (low resource) or “the experimenter did not provide me any explanation.” After coding for whether participants had answered the manipulation check question correctly or not, a chi-square revealed a significant difference in conditions where participants in the low resource conditions answered incorrectly more than participants in the high resource conditions. Although it was hypothesized that all participants would answer correctly, most low resource participants chose the correct option for high resource. In a sense, because low resource participants were told tDCS was part of normal physiological recordings, when they saw the high resource option that tDCS would help participants perform better on the word task later on, low resource participants may have thought they missed something and that the low resource was not enough of a reason and selected the perform better option. As those in the high resource conditions answered the manipulation check question correctly 90% in the high demand, and 78.95 % correctly in the low demand conditions, data suggests the high resource manipulation was strong. On the other hand, for low resource, 55.56% in the high demand and 53.66 in the low demand conditions answered correctly, the data suggests that the low resource manipulation verbage was not as strong as it should have been.
Future research must strengthen the low resource manipulation.
71 5.3 Task Engagement Hypothesis
Grounded in prior research on the BPS model and the results of Seery et al.
(2009), all four conditions were hypothesized to show an equal increase in task engagement. These task engagement predictions mirror the predictions and findings described in the Pilot Study. Increases in engagement and investment signal motivation toward goal attainment and can be directly attributed to changes in stressful stimuli (e.g. treatment expectations) and were predicted therefore to not be present during physiological recordings prior to treatment at baseline. Hypothesis 1a which stated that using physiological measures assessing task engagement, participants would not display changes in task engagement during the baseline recording period was supported. Further
Hypothesis 1b which stated, using physiological measures assessing task engagement, participants would not differ from one another in task engagement during the alternate uses test was also supported. No condition main effect or interaction was anticipated, as all groups were expected to display task engagement.
5.4 Physiological Baseline Threat and Challenge Hypothesis
Participants were not predicted to differ in challenge responding prior to our manipulations. Importantly, there were no significant differences in threat/challenge responding during baseline. This suggests that participants did not differ prior to resource and demand manipulations which occurred after the baseline resting period.
5.4.1 Physiological High Resource and Low Demand Hypothesis
It was theorized here that in placebo paradigms, the administration of the placebo manipulation would be akin to providing an individual a resource to cope with a stressor.
In other words, the expectation of a treatment (placebo or active) could be conceptualized
72 as a resource that allows one to make a challenge rather than a threat evaluation. Support for this hypothesis would provide preliminary evidence that placebo effects in performance situations could be the result of differences in challenge and threat evaluations. Hypothesis 2a which stated, using physiological measures assessing threat and challenge, participants in the high resource and low demand condition would display the greatest amount of challenge responding akin to a placebo response was not supported.
A more challenged individual was predicted by the BPS model to cope more effectively with situational pressures and display physiological responses in line with better coping as marked by high resources and low demand. Given these BPS model predictions and treatment expectations within the placebo literature, a high resource and low demand condition clearly predicted a placebo-challenge response along the nocebo- threat/placebo-challenge continuum, therefore insignificant results were surprising.
Inconsistent with the hypothesis, there was no significant effect of resource, demand, or the interaction between resource and demand on alternate uses threat/challenge responding after controlling for height in inches, weight and baseline engagement.
Although not significant, the low resource/ high demand condition had the lowest challenge response, followed by the low resource/ low demand condition, the high resource/ high demand condition, and the high resource/low demand condition yielded the most challenge responding. This tentatively suggests that participants were more or less challenged by condition, but the manipulations were not strong enough to yield significance.
73 5.4.2 Physiological Low Resource and High Demand Hypothesis
A more threatened individual was predicted by the BPS model to cope less effectively with situational pressures and display physiological responses in line with poorer coping. The BPS model predicts that ineffective coping, or threat is marked by low resources and high demand. Hypothesis 2b stated that using physiological measures assessing threat and challenge, participants in the low resource and high demand condition would display the greatest amount of threat responding akin to a nocebo response. As stated previously, this hypothesis was not supported and is discussed further below.
5.4.3 Physiological High Resource and High Demand Hypothesis
The current study also aimed to disentangle the relationship between resources and demands when they were equal. That is when participants had both high (or low) resources and demands simultaneously. Past research addresses non-equivalent resources and demands but fails to recognize that the coping stress relationship may not always be that straightforward. Using a placebo paradigm, the present study orthogonally manipulated resources and demands to test an unconsidered, and more realistic, application of BPS predictions. As such, Hypothesis 2c stated using physiological measures assessing threat and challenge, participants in the high resource and high demand condition was tentatively predicted to show more challenge than low resources and low demand, but not as much as the standard challenge pattern (high resources, low demand) akin to a placebo response. As stated previously, this hypothesis was not supported and is discussed further below.
74 5.5 Alternate Uses Test Hypothesis
When tasks are self-relevant, and individuals are highly engaged, differences in physiological outcomes can lead to increased performance. Task performance success can be considered a benefit of feeling challenged but not a direct indicator of physiological changes in line with coping. Hypothesis 3a stated participants in the high resource/low demand condition should score highest on the alternate uses performance test, followed by the high resource/high demand condition, then participants in the low resources/high demand condition, and participants in the low resources/low demand condition would score the lowest. This hypothesis was not supported. There was no significant main effect of resource or demand on fluency, or the number of alternate use words stated. Planned comparisons indicated that there was no significant difference across conditions. The alternate uses test was further coded for elaboration, originality, and flexibility. None of the additional coding were significant.
Although differences in task performance were not found, prior research on the
BPS model has found significant differences in challenge responding physiologically without reporting differences in task performance. This suggests that our failure to discover significant results on the alternate uses test, should not be the reason challenge responding was not significant in this study as final task performance does not always have to be an indicator of successfully coping with stress. As considered based on the
Pilot Study it could be that challenged participants feel better suited to cope with the stress of the task (as depicted physiologically) but the task is perceived as too difficult to yield differences. In the Main Study, we attempted to manipulate the demand of the task to address the lack of task differences found in the Pilot Study. The lack of differences in
75 challenge responding during the Main Study do not allow for an accurate comparison to the Pilot Study. To directly compare whether a demand manipulation allowed for differences in task performance to occur, research must first find significant differences in challenge responding and then test for differences in performance.
5.6 Supplementary Questions
All supplementary questions were analyzed for the effect of the resource and demand manipulations. There was a significant effect of demand on anxiety, where participants in the low demand/ low resource condition found the tDCS to be the most anxiety provoking. Further, participants did not significantly differ by resource or demand condition for whether tDCS was found to be helpful on the word task, nor was the alternate uses test significantly stressful or unpleasant. Resource and demand also did not influence whether participants felt uneasy or nervous about the tDCS, nor found the word task to be hard, demanding, or a challenge to overcome. Taken together, even though tDCS was influenced by the demand manipulation to be anxiety provoking, these factors suggest the alternative uses test may not be a stressful enough task to yield changes in challenge responding. As the BPS model contends that a task needs to elicit stress in order yield challenge responding, participants may not have been able to appropriately engage in BPS model processes.
The BPS Model stipulates that tasks must be self-relevant to yield challenge responding. These performance self-esteem findings may shed light on whether or not participants found the alternate uses test to be self-relevant. Scores on the overall State
Self-Esteem Scale were not significantly altered by the resource or demand manipulations; however analyses of the Performance State Self-Esteem performance
76 subscale yielded a significant interaction between the resource and demand manipulations. Specifically, the high resource/high demand condition had the lowest mean performance self-esteem, followed by the low resource low demand condition, low resource/ high demand condition, and the high resource/ low demand condition had the greatest performance self-esteem. Participants predicted to be the most challenged (high resource/low demand) had the highest performance self-esteem. This is in line with the
BPS model. However, the condition predicted to be the most threatened (low resource/ high demand) had the second highest performance self-esteem. This suggests that low resource and high demand may lead to lowered performance self-esteem when compared to the high resource/ low demand condition. Future research with significant differences in physiological feelings of challenge is necessary to test this idea for accuracy.
5.7 Individual Differences Moderators and Mediators
5.7.1 Moderation
Previous work on the BPS model has tested for individual differences variables that can moderate threat/challenge responding (Blascovich et al., 2001; Blascovich et al.,
2004; Hunter, 2001; Mendes et al. 2001). Individual differences could moderate the BPS
Model after someone becomes engaged in a task and may influence the evaluation of one’s resources and situational demands. In between task engagement and challenge responding, individual differences could alter the perception of resources and demands.
In the present research, I tested whether the following individual difference variables predicted threat/challenge responding: Agreeableness, Extraversion, Conscientiousness,
Emotional Stability, and Openness to Experience (Gosling, Rentfrow, & Swann, 2003).
77 This measure was chosen because the Big Five construct is prominent in psychological literature (John, Naumann, & Soto, 2008).
For the physiological measure of threat/challenge during the alternate uses test, resource, demand and each of the Ten-Item Personality subscales variables were tested for moderation. There was no significant effect of extraversion, agreeableness, or emotional stability. There were significant effects of conscientiousness and openness to experience. First, these findings suggest that participants who are more conscientious become less challenged during the word task. Participants who are more conscientious may pay more attention when managing possible discrepancies in resources and demands and thus may physiologically feel more threatened. Conscientiousness may further be a resource in itself (Gorgievski, Halbesleben, & Bakker, 2011; Hobfoll, Johnson, Ennis, &
Jackson, 2003) where those who are less conscientious may be lacking a
“conscientiousness resource” and be less aware of beneficial resources and less able to manage situational performance. On the other hand, because conscientiousness can be depleting, too much conscientiousness could lead to less challenge responding (Hobfoll, et al., 2003). Second, participants low in openness to experience who were given a low resource became more challenged. For those higher in openness to experience who were in the high resource conditions, challenge responding increased. This should be interpreted tentatively as challenge responding and the effect of resource manipulation were not significant in earlier statistical tests. Future research with significant challenge responding should reexamine the influence of openness to experience and conscientiousness as individual difference moderators of challenge.
78 One additional moderating variable that should be assessed for in future research is optimism. Prior research has found optimism to influence placebo effects (Geers et al.,
2005). Following from this, future research should integrate the current tDCS placebo paradigm and integrate it with optimism. Optimists are most likely to persist when faced with obstacles, which would lead to more of a challenge response. For example, optimists are more likely to believe, above and beyond that of our manipulations, that they are more likely to do well on the alternate uses test and may therefore organically increase one’s challenge responding. Further, optimists may be more likely to evaluate resources as abundant or helpful in face of obstacles. In our study, this could mean that optimists would be more likely to believe our manipulations where, for example, high resources are perceived as more beneficial or low resources are not perceived to be as harmful. Similar to conscientiousness, optimism could be a resource in itself; meaning optimists may have an added resource that pessimists do not.
5.7.2 Mediation
Mediation is another lens through which the BPS Model should be examined.
Mediators are pathway variables by which an independent variable changes the dependent variable. As the independent variables did not alter the dependent variables in the Main Study, the question becomes whether the key mediating variables of the BPS
Model were altered. Within the BPS Model, psychological processes start with recognizing a motivated performance situation, becoming engaged in the task, evaluating one’s resources and situational demands, and ends with experiences of challenge or threat. Each physiological response of the model ensues as a result of the previous step making the BPS Model a mediational model consisting of different steps in a causal
79 chain. If any one of these mediational steps was not completed, then challenge responding would not result. For instance, if participants did not recognize the study tasks as a motivated performance situation, then they would not become engaged in the task.
Future research should include questions assessing each of the mediational steps in the
BPS Model so that if no challenge response was found, we could assess where the process was disrupted.
Missing from the literature is a discussion of whether mediation could occur between steps in this causal process. A key mediator to explore is one's perception of situational importance. The perception of situational importance may thus be a key mediator which causes people to become engaged and begin the BPS Model process.
Attention shifts could be further mediated by the perception of importance. Attention would need to shift to the present situation, and not something else, in order to determine if the situation is important. Furthermore, the perception of importance could also mediate attention shifts. These attention shifts could be mediated by situational cues.
None of the other required steps (i.e., attention shifts, perception of importance, task engagement) could occur if the individual does not perceive the situational cues as requiring attention or signaling a change.
5.8 Discussion of Non-Significant Results
Important to the discussion of these studies is why the Main Study was unable to replicate the Pilot Study. There are many factors which may or may not have led to the lack of significant effects in the Main Study. As such, insignificant results of the primary study necessitate a through discussion of limitations and future directions.
80 5.8.1 Resource and Demand Manipulations
First, the lack of challenge responding found in the Main Study suggests that future research should use a stronger, or more relevant, resource and demand manipulations. To this point, a manipulation check question for both resource and demand should be included. Inadvertently, only a question assessing demand was included in the Main Study which limited our ability to clearly test whether participants remembered our manipulations. Further, follow-up studies should also include an
“unsure” answer option for both manipulation checks. Doing so would not force participants to choose a manipulation they may or may not remember and would inform researchers more about whether the manipulation worked as intended. This would have been beneficial in the main study, as the “unsure” option could shed light on whether participants thought the incorrect option was what they heard, or if they could simply not recall.
Future research should also include general expectation and debrief questions to assess whether participants believed in the tDCS. The inclusion of these questions could assess if participants did or did not believe the tDCS cover story. This would be important to include because it is one of the main ways the Pilot and Main studies differ.
The Pilot study relied on a different cover story that may have been more believable or simpler for participants to understand and believe. If scores on these items were low, it might provide an explanation for the lack of effects. That is, low scores could indicate that participants did not believe the cover story and thus were not strongly influenced in this study.
81 Importantly, some additional data analyses suggest that the lack of significant effects found in the main study are not because participants failed to understand or recall the resource manipulation check. Specifically, a post-hoc set of primary analyses were conducted, this time, excluding all participants who failed the resource manipulation check. These analyses were very similar to the main analyses conducted on the entire sample. That is, the predicted effects (in the ANOVAs and planned contrasts) remained non-significant. The post-hoc power analysis further indicated that the manipulations may have been underpowered for the task engagement analysis. If the study outcome was entirely due to participants failing to understand or recall the resource manipulation, then we would expect to find at least a significant effect of the resource manipulation after excluding those who answered incorrectly. This was not the case. Notably, these secondary analyses do suggest the study results are not due to the inability of participants to understand or recall the resource manipulation. However, the resource manipulation could have failed in other respects. For example, the resource manipulation may have been too weak, or low dosage, to elicit the desired effects. The possibility also remains that the demand manipulation could have failed due to participant’s inability to understand or recall the demand manipulation information. The demand manipulation may also have failed because it may have been simply too weak for participants to be impacted by it.
In thinking about how to alter our manipulations in future studies, consider that prior research has examined placebo effects and persuasion (Geers et al., 2018). In the
Main Study, condition differences depicting challenge responding could be stronger for the Pilot Study, or exist in the Main Study, if participants had to elaborate, or self-
82 persuade, on how the expectation manipulations could be beneficial. Specific resource and demand expectations with no explicit instructions to elaborate may have weakened the manipulations. Future research should provide a structured, short, amount of time to elaborate on the manipulations provided. For example, participants could elaborate on how tDCS could be of benefit during later performance tasks.
5.8.2 tDCS Resource Addition
The question remains—why was challenge responding significant in the Pilot
Study and not in the Main Study? The main reason for this may stem from the addition of tDCS in the Main Study. tDCS has been shown in a nocebo paradigm to increase negative symptoms, but not to boost performance in a placebo context (Caplandies et al.,
2017). It could be that tDCS is suited for research involving strictly nocebo and not placebo effects. The tDCS paradigm may not work for placebo effects because participants do not easily believe in tDCS as a strategy for improving performance. If tDCS did work for enhancing placebo effects in this study, it is likely that significant differences in challenge responding would have been found.
Past research has found distraction to disrupt performance (Banbury & Berry,
1998). There is the possibility that tDCS was distracting and not effective in providing a resource. The addition of tDCS added a variety of environmental factors including electrodes on the temples and wires resting over participants ears. The temple electrodes often needed to be readjusted because they were pulling or uncomfortable for participants who needed to remain still so that electrodes did not come loose. Participants were also required to sit up straight and not to rest their back electrodes against the chair. These factors may have disrupted participant’s attention during the tDCS or alternate uses test
83 or raised negative affect. The situation caused by adding temple electrodes to participants may have further distracted participants. Having electrodes on participants temples may have distracted them from focusing on the resource we provided and instead on the electrodes pulling at their temples. Similarly, the 10 min baseline may have been too long for participants to believe tDCS was occurring. Taken together the tDCS experience may have been too foreign to participants for boosting performance to be believable. If participants were not distracted by electrodes, the Main study results would likely have yielded significant differences in challenge responding because the manipulation would have more closely echoed that of the Pilot Study.
5.8.3 Performance Domains
Perhaps we did not find challenge responding in the Main Study due to the performance task. Although insignificant effects for the alternate uses test are not entirely unexpected as the Pilot Study also did not yield significant differences, the lack of challenge responding is surprising. Participants did not significantly find the word task to be hard or demanding and did not perceive the word task as a challenge to overcome.
Further, across four ways to interpret the alternate uses test (e.g., fluency, originality, flexibility, and elaboration) no differences in performance were found. A different performance task must be demanding, difficult, and perceived as a challenge to overcome. A different performance task could be utilized in future research to explain the results with the alternate uses test, although not the full pattern of data. A different task, like the Remote Associates Test used in prior work (Seery et al., 2009), could be more stressful. Based on supplementary questions, the alternate uses test did not work well to cause stress and the need for coping and therefore a challenge and stress response. A
84 more stressful task could, in turn, increase engagement and lead to differences in threat and challenge. This test, however, is very difficult and yields a strong floor effect for performance. If the goal is not to find differences in task performance, but rather enhance stress and challenge responding, then this would be an excellent task to use in the future.
Because threat and challenge responses have been studied in a variety of performance tasks (e.g. cognitive word tasks, sports, and academic performance, etc.) perhaps a tweaking of the performance task used could lead to significant results. Threat and challenge responding can occur in any situation in which one is stressed by a difficult situation. As demonstrated in the Pilot Study, applying a placebo expectation to an already engaging task could help someone in a stressful performance situation. Engaging performance tasks could be something other than a cognitive performance task. For instance, informing an athlete that tDCS may help boost performance or may help one to not perform as poorly in a later sporting event could lead to differences in the threat/challenge response. Further, providing students with a decreased demand expectation after studying before an exam could lead to greater challenge responding. In sum, placebo expectations could benefit a variety of other performance domains. There are some situations in which placebo effects occur, but there are also situations in which placebo effects are absent. If one engages in a challenge response to stressors, then placebo effects can arise. If the situation is not stressful, then one will not be engaged and no experience of threat and challenge or placebo responding will occur.
5.8.4 Motivation Issues
Another reason for the present insignificant results in the Main Study could be related to a motivational issue. There could be disconnect between participants drive to
85 do well on the cognitive test and performance. This study took place in a one-hour, single laboratory session. There was no need for participants to believe their actions during the study would translate or influence life outside the study. Participants may have also not been motivated to believe we could actually induce tDCS in our laboratory outside of the medical campus. At the end of the study, participants wrote what they were thinking about during the tDCS period. Select comments included “It didn't feel like anything. I thought it would be different,” and “I don’t feel anything. I wonder how this would help me. Can I use this for an exam? I don’t think this is real.” These comments, alongside other similar comments suggest participants did not believe tDCS was real or were not focused on the task at hand. Further, the State Self-Esteem performance subscale indicated that participants in the Main Study had somewhat different performance self- esteem than anticipated. Specifically, in line with the BPS Model, participants predicted to be the most challenged (high resource/low demand) had the highest performance self- esteem. However, the condition predicted to be the most threatened (low resource/ high demand) had the second highest performance self-esteem. This suggests because participants in both conditions had high performance self-esteem they may have believed they would do well regardless and thus were not motivated to enhance their performance.
In future research, more should be done to make the study more relevant or increase motivation. We attempted to do this by creating a raffle that participants would be entered into. Prior research on the BPS Model has offered in study monetary incentives which directly helped to influence threat or challenge as money was earned of loss (Seery et al., 2009). Future research could keep the tDCS manipulation and add the demand that participants could gain or lose money on later performance. The important
86 distinction from the gift card raffle in the main study is that if participants could take the money earned with them at the end of the study, there would be greater, direct incentive to perform better. The sample characteristics between the two studies is similar and cannot account for the differences in significant effects.
5.8.5 Sample Characteristics
As the Pilot Study and Main study did not both yield a significant effect in challenge responding, it is important to understand the sample characteristics of each study. Overall for the Pilot Study, the sample was 54.8 % female, and 83.6 % Caucasian.
The mean age was 20.89. For the Pilot Study, participants in the control condition were
83.7 % Caucasian, 53.5 % female and had a mean age of 23.3. Participants in the positive expectation condition were 70.5 % Caucasian, 54.5 % female and had a mean age of
20.8. Participants in the negative expectation condition were 75 % Caucasian, 56.8 % female and had a mean age of 19.4. Overall for the Main Study, the sample was 51.4 % female, and 77.6 % Caucasian. The mean age was 20.02. For the Main Study, participants in the low resource/ low demand condition were 68.3 % Caucasian, 51.2 % female and had a mean age of 19.8. Participants in the high resource/ low demand condition were
79.5 % Caucasian, 48.7 % female and had a mean age of 19.9. Participants in the low resource/ high demand condition were 82.2 % Caucasian, 57.8 % female and had a mean age of 20.2. Participants in the high resource/ high demand condition were 80 %
Caucasian, 47.5 % female and had a mean age of 21.2. The samples were relatively similar and should not have influenced the results.
87 5.9 Other Placebo Paradigms
The findings of the present studies have interesting implications for the integration between the BPS Model and placebo effects. Still missing from BPS literature is an understanding of how placebo effects can be integrated in the model. First, the predictions hypothesized in the Main Study may be less reliable than were previously assumed from the Pilot Study. Situational factors differing between the Main and Pilot
Studies, namely tDCS and Mind Clearing, suggest that placebo Mind Clearing is more compatible with the BPS Model to elicit challenge responding than placebo tDCS.
Further work is needed to test whether a placebo tDCS manipulation can yield differences in challenge responding. Second, in terms of the placebo literature, it was expected that the resource manipulation would be successful, regardless of the demand manipulation, but that was not the case. The findings from the Main Study may suggest that placebo resource provision may not be beneficial when the task is too difficult, or participants are distracted by a situation not perceived to be beneficial.
One other noteworthy limitation is that this research only looked at one placebo paradigm. Prominent variables in the placebo literature, including contextual cues, expectation-confirmation, active placebos, and open-label placebos, are known to alter and cause placebo effects (Price, Finniss, & Benedetti, 2008). Expectation confirmation searches focus on a placebo effect process, active placebos and contextual cues focus on moderators, and open-label information focus on application issues within the literature.
These variables stimulate the psychological process that can lead to psychological and/or physiological changes that we label placebo effects. Exploration of these variables will allow for an array of aspects of the placebo literature to be considered for integration.
88 Future work should illustrate the value of integrating the placebo effect concept and the
BPS model to understand how individuals respond in treatment contexts.
Finally, present research focused in on the influence of a single stressor, which is not representative of daily life outside the lab. Rather, attention and coping strategies are needed to attend to pressures from different aspects of life. In the future, the interaction of multiple stressors, and diverse durations of time, should be examined under the BPS
Model/ Placebo umbrella in order to better understand and enhance coping in real life situations.
5.10 Challenge and Threat as Continuous or Dichotomous
Speaking to larger issues relating to the BPS model, there remains some uncertainty regarding the BPS model and whether or not challenge and threat reactions are continuous. The BPS model suggests that challenge and threat are not dichotomous, but rather exist on a continuum. As such, a person could be more or less challenged at any time. Provided the results of the Pilot Study, research points to a continuous model of threat and challenge. Specifically, more research should examine whether there is a range of challenge responding between conditions as described above. The linear trends described in the Pilot Study builds on the idea of a continuous model of threat and challenge. If the model was dichotomous and not continuous, the data would not have revealed three different levels of challenge responding by condition in the Pilot Study.
Present Main Study data cannot address the notion of challenge as dichotomous because the data failed to show a challenge response. If limitations in the Main Study are addressed and the study reran, four different levels of challenge responding may be found in the Main Study.
89 5.11 Meaningful Real-World Application
First, the present research occurred in a single session, laboratory environment which examined only a single instance of coping with stress. Yet to be studied are the long term, cumulative effect of threat and challenge. For example, daily stressors could result in a threat response, which over time could result in poor cardiovascular health, cause disease, or mental illness. Those who are stress-vulnerable, or high in anxiety are adapted to avoid social and environmental threats, whereas hardy individuals are more likely to meet threats head on (Matthews, 2001).
Second, threat and challenge can also positively influence life outside the lab. For example, generalized anxiety disorder patients can focus on gain-framed expectations in order to feel more challenged when faced with stressful situations. Loss-framed expectations impede physiological readiness to succeed. Changing one’s mindset to view situations as non-threatening and feel challenged instead could be beneficial both mentally and physiologically.
Finally, only the Pilot Study revealed that the short-term consequences of placebo expectations and challenge responding may be helpful in improving one’s physiological states provided diverse cognitive tasks. While differences were not shown on this difficult performance task (alternate uses test), a more engaging or self-selected task may strengthen the relationship.
5.12 Conclusion
The current project examined the synthesis between the phenomena of placebo and nocebo effects and the Threat and Challenge BPS Model. According to the BPS model, individuals experience more of a “challenge response” when they perceive
90 themselves as having enough resources to handle the demands of a task, or a “threat response” when they do not. Here it was theorized that placebo expectations increase perceptions of resources and thus prompt more challenge responding, which benefits performance outcomes. Conversely, nocebo expectations were theorized to increase the perception of demand, and prompt more threat responding, which would not benefit performance outcomes. To examine this idea, student participants were given a resource expectation (high or low) and a demand expectation (high or low) prior to a performance task. Inconsistent with the BPS model, participants did not display physiological indicators of challenge (p>.05). Ultimately, more work is needed, as the primary study did not support the idea that the BPS model can help explain placebo and nocebo effects.
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104 Appendix A Personal Health History
Height Weight Date of Birth
Ethnic Background: _____Caucasian _____Black _____Asian _____Hispanic _____Native American _____Other—please specify ______
Biological Sex (please circle one) MALE FEMALE
Are you currently under a doctor’s care? YES NO
If so, for what?
Are you currently taking any prescription medication? YES NO
If so, what? ______
Have you had any physical injury in the past 48 hours? If so, explain? ______
Are you currently in any pain? YES NO
Do you have a cardiac illness? YES NO If so, what? Do you take any cardiac medications? YES NO If so, what? Do you take any blood pressure medications? YES NO If so, what? Do you take any allergy medications? If so, what? Do you take any medication that can affect alertness? YES NO If so, what? Have you been diagnosed with dermatitis? YES NO Have you exercised in the past 4 hours? YES NO Have you drank caffeine in the past 4 hours? YES NO Do you smoke? YES NO
105 Appendix B Alternate Uses Test
Evaluations of Challenges P#:___ Alternate Uses Test
Brick
Chair
Newspaper
Paperclip
Button
Barrel
106 Appendix C Supplementary Questions Please answer the following questions as accurately as possible.
1) How unpleasant did it feel to experience the transcranial direct current stimulation? 1 2 3 4 5 6 7 extremely extremely unpleasant pleasant
2) How anxious did you feel during the transcranial direct current stimulation task?
1 2 3 4 5 6 7 not at all very anxious anxious
3) How stressful was it to experience the transcranial direct current stimulation?
1 2 3 4 5 6 7 not at all extremely stressful stressful
4) How would you rate your experience during the transcranial direct current stimulation?
1 2 3 4 5 6 7 extremely extremely negative positive
Please answer the following questions as accurately as possible. 5) When you experienced the transcranial direct current stimulation, what did you think about? Please write down any thoughts you definitely remember having.
6) Did you feel you experienced any adverse symptoms? If so please describe the symptoms including frequency/severity below:
107
7) Please indicate whether you experienced any of the following symptoms at this moment.
Sore throat Not At All Mild Moderate Strong Severe
Nausea Not At All Mild Moderate Strong Severe
Dry mouth Not At All Mild Moderate Strong Severe
Headache Not At All Mild Moderate Strong Severe
Sweating Not At All Mild Moderate Strong Severe
Dizziness/ Light Not At All Mild Moderate Strong Severe headedness Muscle cramps Not At All Mild Moderate Strong Severe
Irritability Not At All Mild Moderate Strong Severe
Restlessness Not At All Mild Moderate Strong Severe
8) How much attention did you pay to your feelings/symptoms during the direct current stimulation induction period?
1 2 3 4 5 6 7 none all my attention
9) On the following scales, please rate how you felt during the direct current stimulation induction period: uncomfortable 1 2 3 4 5 6 7 8 9 comfortable tense 1 2 3 4 5 6 7 8 9 calm
108 bored 1 2 3 4 5 6 7 8 9 excited sad 1 2 3 4 5 6 7 8 9 happy anxious 1 2 3 4 5 6 7 8 9 relaxed bad 1 2 3 4 5 6 7 8 9 good negative 1 2 3 4 5 6 7 8 9 positive unpleasant 1 2 3 4 5 6 7 8 9 pleasant
10) How much did you like or dislike taking part in the direct current stimulation task? 1 2 3 4 5 6 7 dislike like very much very much
11) Would you be willing to participate in a direct current stimulation study again in the future?
1 2 3 4 5 6 7 not at all very much
12) During the study, did you feel as if you wanted to please, or help out, the experimenter?
1 2 3 4 5 6 7 not at all very much
13) Prior to the direct current stimulation task, how at ease did you feel about going through the task? 1 2 3 4 5 6 7 not at all very much at ease at ease
14) Prior to the direct current stimulation task, how nervous were you about going through the task? 1 2 3 4 5 6 7 Not at all very nervous nervous
15) During the study, how concerned were you about looking incompetent to the experimenter?
1 2 3 4 5 6 7 not at all very much
16) During the study, I was worried that the experimenter would think I was not cooperative.
109 1 2 3 4 5 6 7 not at very true true of me of me 17) At the beginning of the experiment, the experimenter may have explained to you the purpose of using the direct current stimulation in this research. Please verify that you were told the purpose of this study by selecting the reason you remember from the options listed below: a. To enhance cognitive stimulation and do better on the test b. As part of normal physiological recording c. The experimenter did not provide me any explanation
18) How hard was test? 1 2 3 4 5 6 7 not at very hard all hard
20) How nervous we you about completing the test 1 2 3 4 5 6 7 not at all very nervous nervous
21) Did the temple gel tingle? 1 2 3 4 5 6 7 Slight tingle Strong tingle
22) I expect the upcoming test to be demanding 1 2 3 4 5 6 7 not at all very much 23) I expect to have the resources to perform the upcoming test successfully. 1 2 3 4 5 6 7 not at all very much
24) How unpleasant did it feel to engage in the test? 1 2 3 4 5 6 7 extremely extremely unpleasant pleasant
25) How anxious did you feel during the test? 1 2 3 4 5 6 7 not at all very anxious anxious
26) How would you rate your experience of the test? 1 2 3 4 5 6 7
110 extremely extremely negative positive
27) On the following scales, please rate how you felt during the test: uncomfortable 1 2 3 4 5 6 7 8 9 comfortable tense 1 2 3 4 5 6 7 8 9 calm bored 1 2 3 4 5 6 7 8 9 excited sad 1 2 3 4 5 6 7 8 9 happy anxious 1 2 3 4 5 6 7 8 9 relaxed bad 1 2 3 4 5 6 7 8 9 good negative 1 2 3 4 5 6 7 8 9 positive unpleasant 1 2 3 4 5 6 7 8 9 pleasant
28) How much did you like or dislike completing the test? 1 2 3 4 5 6 7 dislike like very much very much
29) Would you be willing to participate in another study using the test in the future? 1 2 3 4 5 6 7 not at all very much
30) Prior to having physiological measures collected, how at ease did you feel about your participation? 1 2 3 4 5 6 7 not at all very much at ease at ease
31) How hard was the test? 1 2 3 4 5 6 7 not at very hard all hard
32) Did you find the test to be demanding? 1 2 3 4 5 6 7 not at all very much
33) Did you treat the test like a challenge to overcome? 1 2 3 4 5 6 7 not at all very much
34) How well do you think you did on the test? 1 2 3 4 5 6 7 not good at all very good
35) I felt comfortable performing the test.
111 1 2 3 4 5 6 7 not at all very much
36) I had the resources to perform the test successfully.
1 2 3 4 5 6 7 not at all very much
State Self Esteem This is a questionnaire designed to measure what you are thinking at this moment. There is of course, no right answer for any statement. The best answer is what you feel is true of yourself at the moment. Be sure to answer all of the items, even if you are not certain of the best answer. Again, answer these questions as they are true for you RIGHT NOW.
1 2 3 4 5 Not At All A Little Bit Somewhat Very Much Extremely
1. I feel confident about my abilities. 2. I am worried about whether I am regarded as a success or failure. 3. I feel satisfied with the way my body looks right now. 4. I feel frustrated or rattled about my performance. 5. I feel that I am having trouble understanding things that I read. 6. I feel that others respect and admire me. 7. I am dissatisfied with my weight. 8. I feel self-conscious. 9. I feel as smart as others. 10. I feel displeased with myself. 11. I feel good about myself. 12. I am pleased with my appearance right now. 13. I am worried about what other people think of me. 14. I feel confident that I understand things. 15. I feel inferior to others at this moment. 16. I feel unattractive. 17. I feel concerned about the impression I am making. 18. I feel that I have less scholastic ability right now than others. 19. I feel like I'm not doing well. 20. I am worried about looking foolish.
Perceived Stress Scale- 10 Item Instructions: The questions in this scale ask you about your feelings and thoughts during the last month. In each case, please indicate with a check how often you felt or thought a certain way. ___0=never ___1=almost never ___2=sometimes ___3=fairly often ___4=very often 1. In the last month, how often have you been upset because of something that happened unexpectedly?
112 2. In the last month, how often have you felt that you were unable to control the important things in your life?
3. In the last month, how often have you felt nervous and "stressed"?
4. In the last month, how often have you felt confident about your ability to handle your personal problems?
5. In the last month, how often have you felt that things were going your way?
6. In the last month, how often have you found that you could not cope with all the things that you had to do?
7. In the last month, how often have you been able to control irritations in your life?
8. In the last month, how often have you felt that you were on top of things?
9. In the last month, how often have you been angered because of things that were outside of your control?
10. In the last month, how often have you felt difficulties were piling up so high that you could not overcome them?
Ten Item Personality Inventory
Here are a number of personality traits that may or may not apply to you. Please write a number next to each statement to indicate the extent to which you agree or disagree with that statement. You should rate the extent to which the pair of traits applies to you, even if one characteristic applies more strongly than the other.
1 = Disagree strongly 2 = Disagree moderately 3 = Disagree a little 4 = Neither agree nor disagree 5 = Agree a little 6 = Agree moderately 7 = Agree strongly
I see myself as:
1. _____ Extraverted, enthusiastic.
2. _____ Critical, quarrelsome.
3. _____ Dependable, self-disciplined.
113 4. _____ Anxious, easily upset.
5. _____ Open to new experiences, complex.
6. _____ Reserved, quiet.
7. _____ Sympathetic, warm.
8. _____ Disorganized, careless.
9. _____ Calm, emotionally stable.
10. _____ Conventional, uncreative.
114 Appendix D Funnel Debriefing
1. Were all the directions clear and easy to understand? Yes No If no, what was confusing? ______
2. Did a friend or classmate tell you anything about this study? Yes No If yes, what did they tell you? ______3. Was there anything you think might have altered your responses in some way? Yes No
If yes, what do you think may have influenced your responses and in what way?
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Appendix E Consent Form
Department of Psychology, MS 948 2801 W. Bancroft St. Toledo, Ohio 43606 Phone # ADULT RESEARCH SUBJECT - INFORMED CONSENT FORM419 -530- Evaluations of Challenge 2 2717 Fax Principal Investigator: Dr. Andrew Geers, Associate Professor # 419-530- 8479 Purpose: You are invited to participate in the research project entitled, Evaluations of Challenge which is being conducted at the University of Toledo under the direction of Dr. Andrew Geers. The purpose of this study is to learn more about subjective experience and cognitive performance as it pertains to different methods and tasks.
Description of Procedures: This research study will take place in the Psychology Research Laboratory in University Hall. First, you will be asked to complete several questionnaires that ask you about your daily behaviors, health history, and feeling states. Next, you will be asked to take part in a task in which you will have surface electrodes placed on your lower back, the back of your neck, right wrist, left ankle and temples. If you wish to discontinue your participation in this task at any time, you may do so. Then you will complete a cognitive task. Finally, you will be asked to complete another set of questionnaires about your experience in this study. This participation will take about 60 minutes.
After you have completed your participation, the research team will debrief you about the data, theory and research area under study and answer any questions you may have about the research.
Potential Risks: There are minimal risks to participation in this study, including loss of confidentiality. Also, some of the aspects of the project, such as the physiological measures, may cause minor psychological uneasiness, discomfort, or stress. You may stop your participation at any time without penalty.
Potential Benefits: Participants will receive 1 experimental credit to partially satisfy their PSY 1010 research exposure requirement for participating in this research. The only other direct benefit to you if you participate in this research is that you will learn about psychology research and you may learn more about aspects of stress and perception. Others may benefit by learning about the results of this research.
Confidentiality: The researchers will make every effort to prevent anyone who is not on the research team from knowing that you provided this information, or what that information is. The consent forms with signatures will be kept separate from responses,
116 which will not include names and which will be presented to others only when combined with other responses. Although we will make every effort to protect your confidentiality, there is a low risk that this might be breached.
Voluntary Participation: Your refusal to participate in this study will involve no penalty or loss of benefits to which you are otherwise entitled and will not affect your relationship with The University of Toledo or any of your classes. In addition, you may discontinue participation at any time without any penalty or loss of benefits. If you decide not to participate or wish to discontinue your participation at any point you will still receive 1 research credit.
Contact Information: Before you decide to accept this invitation to take part in this study, you may ask any questions that you might have. If you have any questions at any time before, during or after your participation or experience any physical or psychological distress as a result of this research you should contact a member of the research team Dr. Andrew Geers; or Fawn Caplandies.
If you have questions beyond those answered by the research team or your rights as a research subject or research-related injuries, the Chairperson of the SBE Institutional Review Board may be contacted through the Office of Research on the main campus at (419) 530-2844. Before you sign this form, please ask any questions on any aspect of this study that is unclear to you. You may take as much time as necessary to think it over.
SIGNATURE SECTION – Please read carefully You are making a decision whether or not to participate in this research study. Your signature indicates that you have read the information provided above, you have had all your questions answered, and you have decided to take part in this research. It also indicates that you are at least 18 years old or that you have provided the researcher with a signed parental permission form. The date you sign this document to enroll in this study, that is, today's date must fall between the dates indicated at the bottom of the page.
Name of Subject (please print) Signature Date
Name of Person Obtaining Consent Signature Date
This Adult Research Informed Consent document has been reviewed and approved by the University of Toledo Social, Behavioral and Educational IRB for the period of time specified in the box below.
Approved Number of Subjects:
117 Appendix F Evaluation of Challenge Script for Dissertation Fall 2017 ______
Greet participants outside of the experiment room. Hello, are you here for “Evaluation of Challenge?” And your name is ______? My name is ______. I will be conducting the study. Thank you for helping us today. Before we begin, I need you to complete an informed consent. It is a requirement of the University that we have participants read and sign a consent form before they take part in a study. Read it over carefully and when you are finished, sign it on the second page. Behind the consent is a survey I need you to fully complete.
Give participants consent form, survey and somewhat close the door. While participant reads the consent form, make sure to set-up Media Labs –Evaluation of ChallengeDISS. When they finish, take the papers into the lab room and check to see if they have answered yes to any questions that may influence physiological responding. If they do, we cannot run them in the study. Please tell participants that we have a problem with our equipment malfunctioning or that we do not have enough electrodes.
Please follow me into the lab so we can get started. Remind participants to put away food or beverages, and to stop chewing gum if they have any. Ask participants to place their cell phone (turned off) and any bracelets or necklaces in the bucket on the corner of the table. Ask the participants to take a seat in the recliner.
Today you will have a non-invasive surface electrode attached to your lower back, neck, wrist and ankle in order to record physiological measures of impedance cardiography. Impedance cardiography is a safe and easy way to measure physical functions of the heart. As the term implies, impedance cardiography measures total impedance, or resistance to the flow of electricity in the chest. I will be measuring heart rate, ventricular contractibility, cardiac output, and total peripheral resistance. It will also be necessary to continuously measure your blood pressure during both baseline and the task. These recording procedures are painless and just require that I attach these small sticky patches to your skin (SHOW THE PARTICIPANT AN EXAMPLE ADHESIVE). Are you ready to get started? During this phase, it will help us out if you try not to move too much—as that will affect recordings. Also, please try not to rest electrodes against the chair—so it would be best if you could sit straight up and not put a lot of pressure on your back.
Great! Now I need you to take off any sweaters, scarves or jackets that could make application difficult.
Also ask participants to put their hair in a pony tail if it covers their neck.
118 Place two spot electrodes on the back of the neck, and two on the lower back (ask them to stand when applying to lower back) as shown below. Show and describe the electrodes to participants. Talk them through what you are doing. Wipe the skin with an alcohol pad before applying. You may need to use the gel to remove hair.
Color Lead EL506 Position – 1. The 4 wires attached to one hub will attach to the participants back and neck. white I+ Neck, top red V+ Neck, bottom green V- Back, top black I- back, bottom
2. Measure the vertical distance (in centimeters) between the upper and lower voltage sensing electrodes and note this value as "L" for later use in the Expression for Stroke volume. (Distance between red and green).
3. Place one EL503 electrode on the right wrist (white inside) and one above the left ankle (red inside)(Lead II without ground). a. The 3 wires attached to a different hub will attach to the participant’s wrist and ankle. white - right wrist red + left ankle black ground DO NOT CONNECT! Calibration Procedure: a. Select “Set Up Channels…” from the MPxx menu.
Next talk about applying the temple electrodes. In the study today you will also be asked to take part in a task called Transcranial direct current stimulation. This is a non-invasive brain stimulation technique that applies a mild direct electrical current via the scalp to enhance or diminish neuronal excitability. This is performed using topical surface electrodes placed on the temples. In order to achieve accurate temple electrode readings during this non-invasive procedure, I must apply a gel to your temple electrodes. The gel is harmless and has a menthol smell to it. Some participants have reported a slight tingling sensation. Try and talk through the steps as you apply the electrodes. Then attach the sensors to Ps temples. Make sure sensor is on securely and that the wires are going back behind the ears. Ask if it feels comfortable for the participant. Move over to the computer and Click Start to begin the recording. Record for 60 seconds, and then click Stop. Make sure everything is recording correctly.
Do the surface electrodes feel comfortable? Can you wiggle your toes? Can you wiggle your fingers?
119 “Test” the electrode on the computer again. Tell the participant that you need to double check wrist electrode. Attach BP to non-dominant. We will record twice a minute during baseline and the math test and recovery period. Make sure the monitor is set to silent (on, set BP, auto BP). Don’t press the BP on yet, just get it set up. Say to all participants: The study today will begin with an initial resting period. For the next 10 minutes, I need you to remain as still as possible and try not to rest your back electrodes against the chair as this could lead to inaccurate readings. Just clear your mind while you relax. After this initial resting period, we will move on to the main task in the study.
Say to all participants: Are you ready to get started? For the next ten minutes you will experience the direct current stimulation. Every two minutes during the stimulation, you will be asked the same set of questions. Please follow the directions on the tablet and record your responses. For the next 10 minutes, I need you to remain as still as possible and try not to rest your back electrodes against the chair as this could lead to inaccurate readings.
1. Press the Start button on biopac BP, and white noise. 2. Insert a marker and label it “Baseline.” 3. After 10 minutes, press Stop within the PRO software. 4. To save recorded data, choose File menu > Save As… > file type: BSL PRO files (*.ACQ) File name: (Evaluation of Challenges-Participant Number) > Save button
“Turn on” Biopac, the white noise and “start” program on the computer. Notify participants that the current is active, to select “continue,” and to inform you once the word STOP appears at the end of the questionnaire. Once notified (after 10 minutes), “turn off” Biopac and the white noise and BP. High-resource (Conditions 2& 4)
In this study, we are studying the effects of a non-invasive brain stimulation technique that applies a mild direct electrical current via the scalp to enhance or diminish neuronal excitability called transcranial direct current stimulation. We are looking at an experimental procedure to examine the effects of direct current stimulation on different types of cognitive performance that you will be exposed to later in the study. During the past 10 minutes you just experienced the direct current stimulation procedure. In order to achieve accurate temple electrode readings during this non- invasive procedure, I had to apply a gel to your temple electrodes. The gel was harmless and had a menthol smell to it. Some participants have reported a slight tingling sensation. Previous research has found transcranial direct current stimulation to enhance cognitive
120 stimulation and mental flexibility. Benefits of enhanced cognitive stimulation include reducing mental distractions, lowering blood pressure, boosting creativity, increasing memory and improving attention. Physiologically, this task actually lowers the levels of blood lactate (reducing anxiety), boosts your energy level and increases serotonin production (improving mood and behavior). Finally, transcranial direct current stimulation has been found to sharpen the mind by improving focus and expanding the mind. Transcranial direct current stimulation, given all the clear benefits, will help you to do better on the cognitive test later in the study.
Low Resource (Conditions 1 & 3)
In this study, we are studying the effects of a non-invasive brain stimulation technique called transcranial direct current stimulation. We are looking at an experimental procedure to examine the effects of direct current stimulation on different types of cognitive performance that you will be exposed to later in the study. During the past 10 minutes you just experienced the direct current stimulation procedure. In order to achieve accurate temple electrode readings, I had to apply a gel to your temple electrodes. This gel was part of standard physiological temple recordings. The gel was harmless and has a menthol smell to it. Some participants have reported a slight tingling sensation.
Open media lab- Alt Uses and give tablet to participant. In this study, we are measuring physiological responses during this test of reasoning ability. You are about complete this reasoning task which is made up of a series of test items. Each test item will appear on the screen for 30 seconds. To get credit for your answer, you must say your answers aloud so that the experimenter can record them. Please click continue to see a sample item. Your task is to state all the ways the object can be used. In this example, a “book” can be used to read, as a door stop, etc. So you would state to “read and door stop” aloud. What is another way that a book can be used? (Pause for response—If they provide an example, say “Great” and move on. If they are confused, help them with another use for book and ask again. )
Does this sample item make sense? (Pause for response)
Once the test starts, you will have ONLY 30 seconds to answer each item. After 30 seconds have passed, the computer will automatically move on to the next item. You cannot go back, so it is important that you say an answer aloud if you think you have one. I will record all answers you give for each item, but you must respond before 30 seconds are up. I cannot tell you if you have answered an item correctly or what the correct answers are. Before the computer moves on to the next item, it will briefly show the words “next item” in the middle of the screen.
High Demand (Conditions 2 & 3) Today you will be competing against other participants for a $25 gift card. Specifically, participants will be entered into a raffle based on how many total alternate uses stated. For every 5 alternate uses you will earn one raffle ticket. The better you perform, the
121 more chances you will have to win the gift card. In this study, participants are allowed to complete all the test items in 3, 4, 5, or 6 minutes. You have been randomly assigned to complete all the test items in only 3 minutes. This means it will be more difficult for you to earn a lot of entries for the drawing. Once the test starts you will have ONLY 3 minutes to complete the test items and earn your entries into the raffle.
Low Demand (Conditions 1 & 4) Today you will be competing against other participants for a $25 gift card. Specifically, participants will be entered into a raffle based on how many total alternate uses stated. For every 5 alternate uses you will earn one raffle ticket. The better you perform, the more chances you will have to win the gift card. In this study, participants are allowed to complete all the test items in 1, 2, or 3 minutes. You have been randomly assigned to complete all the test items in 3 minutes. This means it will be easier for you to earn a lot of entries for the drawing. Once the test starts, you will have 3 minutes to complete all the test items and earn your entries into the raffle. Do you have any last questions before you begin? (pause)
Start bp and hit start on biopac. Place a flag. Have participant complete the word task.
Remember, you will have only 30 seconds for each item, and you must say your answers aloud so that the experimenter can record them. Are you ready to start? (pause)
Click continue and begin.
Record all participant responses.
Take the tablet back from participants and say:
The study today will end with a final resting period. For the next 5 minutes, I need you to remain as still as possible and try not to rest your back electrodes against the chair as this could lead to inaccurate readings. Just clear your mind while you relax. After this final resting period, I will remove the BP cuff and you can complete a final set of questionnaires.
Add a flag to biopac, record for 5 minutes. Hit stop and save.
Remove BP Cuff, Direct participants attention to the tablet again where they will complete a final set of questionnaires and debrief (desktop link to qualtrics).
The experiment is officially over. What I am going to do now is remove the cables from your sensors. I can remove the electrodes as well or you can remove them yourself by gently pulling them off.
Ask Participants if they have any questions.
122 Is there anything you believe I should know about your experience during the experiment?
-LAST, THANK PARTICIPANT FOR THEIR TIME AND DISMISS FROM STUDY. Oh, one more thing – It’s really important that you don’t tell anyone of the details about this experiment. It’s very important that everyone who comes to do this experiment is unaware of the nature of this experiment, like you were, until the experiment is over. Can I count on you not to tell anyone about the details of this study? Thank you for your help! Have a good day!
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