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Hormones and Social Affiliation: Menstrual Cycle Shifts in Progesterone Underlie Women's Attention to Signs of Social Support Saul Miller

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Hormones and Social Affiliation: Menstrual Cycle Shifts in Progesterone Underlie Women's Attention to Signs of Social Support Saul Miller Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2011 Hormones and Social Affiliation: Menstrual Cycle Shifts in Progesterone Underlie Women's Attention to Signs of Social Support Saul Miller Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] THE FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES HORMONES AND SOCIAL AFFILIATION: MENSTRUAL CYCLE SHIFTS IN PROGESTERONE UNDERLIE WOMEN’S ATTENTION TO SIGNS OF SOCIAL SUPPORT By SAUL MILLER A dissertation submitted to the Department of Psychology in partial fulfillment of the requirements for the degree of Doctor of Philosophy Degree Awarded: Spring Semester, 2011 The members of the committee approve the dissertation of Saul Miller defended on March 17, 2011. _______________________________________ Jon K. Maner Professor Directing Dissertation _______________________________________ Karin Brewster University Representative _______________________________________ Colleen Kelley Committee Member _______________________________________ Lisa Eckel Committee Member _______________________________________ E. Ashby Plant Committee Member The Graduate School has verified and approved the above-named committee members. ii This dissertation is dedicated to Bill and Lois Miller. iii ACKNOWLEDGEMENTS The author thanks Jon K. Maner for his guidance and mentorship; Colleen Kelley, Lisa Eckel, Ashby Plant, and Karin Brewster for their helpful comments and suggestions; his friends and family for their love and support; and his fiancée, Andrea, for much more than he could possibly list. iv TABLE OF CONTENTS List of Tables ................................................................................................................................. vi Abstract......................................................................................................................................... vii 1. INTRODUCTION...................................................................................................................1 1.1 Factors Shaping Affiliative Motivation .........................................................................1 1.2 An Evolutionary Perspective on Women’s Motivation.................................................2 1.3 A Neuroendocrinological Perspective on Women’s Motivation...................................4 1.4 Lower-Order Cognition and Affiliation: Attention to Social Stimuli............................5 1.4.1 The Social Monitoring System Hypothesis .......................................................6 1.4.2 The Target-Specific Attentional Hypothesis .....................................................6 1.5 Overview of the Current Research.................................................................................8 2. METHOD................................................................................................................................9 2.1 Participants.....................................................................................................................9 2.2 Procedure .......................................................................................................................9 2.3 Progesterone Measurement..........................................................................................11 3. RESULTS..............................................................................................................................12 3.1 Preliminary Analyses...................................................................................................12 3.2 Facial Expression Dot Probe Task...............................................................................13 3.3 Femininity Dot Probe Task..........................................................................................16 4. DISCUSSION........................................................................................................................19 APPENDICES ...............................................................................................................................23 A. IRB APPROVAL......................................................................................................................23 B. CONSENT FORM ....................................................................................................................24 REFERENCES ..............................................................................................................................26 BIOGRAPHICAL SKETCH .........................................................................................................31 v LIST OF TABLES 1 Mean (SD) salivary progesterone values (pg/ml)..................................................................13 2 Mean (SD) reaction time (ms) on the facial expression dot probe task ................................16 3 Mean (SD) reaction time (ms) on the femininity dot probe task...........................................18 vi ABSTRACT The desire for positive social relationships is a fundamental motive shaping human cognition and behavior. In the current research, I integrate social cognitive, evolutionary, and neuroendocrinological theories to generate and test predictions about how female affiliative motives shift naturally across women’s menstrual cycles and how these shifts relate to functional changes in attention. Consistent with a social monitoring system hypothesis, during the luteal phase of their cycle, normally cycling women, but not women on oral contraceptives, displayed greater attentional attunement to social stimuli than non-social stimuli. Moreover, attention to social stimuli was associated with normally cycling women’s levels of progesterone – a hormone closely tied to affiliative motivation. The current research suggests that endocrinological mechanisms are functionally linked with lower-order cognitive processes designed to help foster positive social relationships. vii CHAPTER ONE INTRODUCTION Humans are a highly social species. “Social” because we rely on others every day of our lives for resources, support, and survival. “Species” because we are bound by the evolutionary pressures that shape all living creatures. Accordingly, human psychology and biology have been shaped throughout evolution to facilitate the pursuit of vital social needs. In the current research, I apply this “social species” model of human nature by exploring how biology influences cognitive processes designed to satisfy one of the most fundamental of human needs – the need for positive social relationships (Baumeister & Leary, 1995). In the current research, I integrate neuroendocrinological, evolutionary, and social cognitive perspectives on affiliation and social relationships to generate and test predictions about the ways in which natural hormonal fluctuations associated with women’s reproductive status relate to changes in lower-order social cognition. In particular, I examine how menstrual cycle changes in women’s reproductive status and levels of progesterone – a hormone closely tied to affiliative motivation (Schultheiss, Dargel, & Rohde, 2003) – shapes how women attend to their social world (DeWall, Maner, & Rouby, 2009; Gardner, Picket, & Brewer, 2000; Pickett, Gardner, & Knowles, 2004). 1.1 Factors Shaping Affiliative Motivation Social relationships play a crucial role in helping people solve a variety of important adaptive challenges. Consequently, the need for friendship and positive social bonds is one of the most profound and fundamental of all human needs (Baumeister & Leary, 1995) – one that if not satisfied can lead to devastating consequences for psychological and social well-being (Baumeister, DeWall, Ciarocco, & Twenge, 2005; Leary, 1990). Although all people possess a desire for social closeness and friendship, the strength of this affiliative motivation is by no means constant across all situations and all people. For example, situational factors indicating that one’s affiliative goals are not being met (e.g., social rejection) cause people to increase their desire to form new social bonds and facilitate processes designed to increase the formation of positive social relationships (Maner, DeWall, Baumeister, & Schaller, 2007). Personality characteristics (e.g., a chronic need-to-belong) also influence 1 one’s desires for affiliation (Leary, Kelly, Cottrell, & Schreindorfer, 2005) and shape one’s sensitivity to other people in the social environment (Gardner, Pickett, Jefferis, & Knowles, 2005; Pickett et al., 2004). Thus, several factors shape the strength of one’s affiliative motivation and the degree to which people seek out potential sources of social connection. One factor that has received great attention among scientists interested in affiliative motivation is a person’s sex. Several studies suggest that affiliative motives are particularly strong among women. Women, for example, report greater concerns over relationship vulnerabilities such as negative social evaluations and interpersonal dependency than men do (Rose & Rudolph, 2006). Additionally, women tend to be more reactive to interpersonal stresses (e.g., social exclusion) than men are (Stroud, Salovey, & Epel, 2002; Stroud, Tanofsky-Kraff, Wilfley, & Salovey, 2000). Although on average women tend to have strong affiliative motives, affiliative responses vary considerably across individual women and across studies (Kajantie & Phillips, 2006). Indeed, whereas some studies reveal that interpersonal stressors
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