Psychology of Consciousness: Theory, Research, and Practice The Effects of Exposure to Differing Amounts of Misinformation and Source Credibility Perception on Source Monitoring and Accuracy Michelle M. Pena, J. Zoe Klemfuss, Elizabeth F. Loftus, and Amelia Mindthoff Online First Publication, October 23, 2017. http://dx.doi.org/10.1037/cns0000137

CITATION Pena, M. M., Klemfuss, J. Z., Loftus, E. F., & Mindthoff, A. (2017, October 23). The Effects of Exposure to Differing Amounts of Misinformation and Source Credibility Perception on Source Monitoring and Memory Accuracy. of Consciousness: Theory, Research, and Practice. Advance online publication. http://dx.doi.org/10.1037/cns0000137 Psychology of Consciousness: Theory, Research, and Practice © 2017 American Psychological Association 2017, Vol. 0, No. 999, 000 2326-5523/17/$12.00 http://dx.doi.org/10.1037/cns0000137 The Effects of Exposure to Differing Amounts of Misinformation and Source Credibility Perception on Source Monitoring and Memory Accuracy

Michelle M. Pena J. Zoe Klemfuss Florida International University Florida International University and University of California, Irvine

Elizabeth F. Loftus Amelia Mindthoff University of California, Irvine Florida International University

Although it is well known that exposure to misinformation after an event can alter memory, less known are the effects of being presented with different amounts of misinformation. The present study examined (a) how exposure to different amounts of misinformation affects memory, (b) how sensitively individuals monitor the accuracy of a (mis)information source, (c) whether perceived credibility of the misinformation source mediates the relations between misinformation exposure and memory accuracy, (d) whether perceived source credibility is associated with improved source monitoring, and (e) how exposure to different amounts of misinformation affects the ability to accurately assess one’s own memory performance. Participants watched a mock crime video, were exposed to a misleading narrative about the video containing 20%, 50%, or 80% misinformation, completed a memory test, and rated the credibility of the misinformation source and their own memory performance. Receiving more misinfor- mation decreased memory accuracy. Interestingly, receiving more misinformation also led subjects to become more skeptical of the credibility of the narrative, dampening the negative effect of misinformation on memory accuracy. In addition, individuals’ perceptions of the source’s credibility and source monitoring accuracy were negatively associated. Lastly, participants’ performance estimates and confidence were well cal- ibrated to their actual performance, except when they were misled, supporting the idea that misinformed responses are more difficult to monitor. Participants also tended to overestimate their accuracy, particularly when they performed poorly.

Keywords: misinformation, source credibility, memory accuracy, metacognition

Memory is a constant restructuring process, information in light of what is already known one that consists of incorporating new informa- (see Clifasefi, Garry, & Loftus, 2007; Schacter, tion into old and interpreting new 2001, for reviews). Researchers have reported that this restructuring process can result in memory errors when the new information pre-

This document is copyrighted by the American Psychological Association or one of its allied publishers. sented is incorrect (Belli, 1989; Dodd & Brad- Michelle M. Pena, Department of Psychology, Florida In- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. shaw, 1980; Loftus, 1975; Loftus, 1979). These ternational University; J. Zoe Klemfuss, Department of Psy- chology, Florida International University, and Department of findings have led to further explorations of the Psychology and Social Behavior, University of California, processes that may be at play within the misin- Irvine; Elizabeth F. Loftus, Department of Psychology and formation effect in efforts to provide possible Social Behavior, University of California, Irvine; Amelia Mindthoff, Department of Psychology, Florida International explanations as to why individuals incorporate University. postevent misinformation into memory. Under- Correspondence concerning this article should be ad- standing the cognitive and metacognitive as- dressed to J. Zoe Klemfuss, Department of Psychology and pects of memory, such as the ability to monitor Social Behavior, University of California, Irvine, 4201 So- cial and Behavioral Sciences Gateway, Irvine, CA 92697. postevent information for accuracy, to accu- E-mail: [email protected] rately distinguish an experienced memory from

1 2 PENA, KLEMFUSS, LOFTUS, AND MINDTHOFF

postevent misinformation, and to correctly as- to as a source misattribution error (Belli, Lind- sess one’s own memory performance, has im- say, Gales, & McCarthy, 1994; Zaragoza & portant implications for our theoretical under- Lane, 1994). In line with an integrated model of standing of how the the misinformation effect, research suggests occurs. that source monitoring is a cognitive process In the present study, we examined contextual that can be affected by social factors such as the and individual difference effects on resistance to perceived credibility of the postevent source false information provided after exposure to a (Skagerberg & Wright, 2009). mock crime. Specifically, we explored (a) whether increasing the proportion of misinformation to Source Credibility and neutral information negatively impacts memory accuracy, (b) how sensitively individuals monitor Memory Performance the accuracy of a (mis)information source, (c) People who are given warnings about the whether perceived credibility of the misinforma- credibility of the source of postevent informa- tion source mediates the relations between misin- tion (e.g., that the source is not credible, or that formation exposure and memory accuracy, (d) the source is someone who may have motiva- whether perceived source credibility leads to im- tion to deceive) scrutinize the features of the proved source monitoring, and (e) the accuracy of source more than those who are not given a participants’ self- evaluations of memory perfor- warning. This additional scrutiny allows the mance. By collectively examining these issues, warned group to more effectively monitor their the present study was designed to provide addi- memories and to dismiss misleading items (e.g., tional support for the negative impact of misinfor- Echterhoff, Hirst, & Hussy, 2005; Frost, Ingra- mation on memory accuracy, but more impor- ham, & Wilson, 2002; Skagerberg & Wright, tantly, the design allowed for the investigation of 2009). However, although research suggests factors (perceived source credibility, source mon- that individuals are capable of making credibil- itoring accuracy) that may be heightened in the ity judgments from implicit warnings (e.g., the face of high rates of misinformation and aid in the source is the driver who caused the accident resistance to that misinformation. Further, we being described), it is less clear whether indi- were able to determine how effectively partici- viduals are able to make such judgments based pants are able to monitor their memory perfor- solely on the content of postevent misinforma- mance when misinformed. tion without alluding to any specific character- istic of the source that may affect credibility Misinformation and Memory Performance judgments. It is important to examine cues to credibility that are intrinsic to the actual quality Provision of false information between a to- of the information received, as they are in many be-remembered event and of that event is cases in the real world. a common source of (Loftus & Hoffman, 1989). The misinformation effect has the potential to influence memory of an original Discrepancy Detection and event, which can lead to decreased accuracy at Memory Performance recall (Belli, 1989; Loftus & Hoffman, 1989; Loftus, Miller, & Burns, 1978; Weingardt, Lof- Existing literature on the principle of discrep- This document is copyrighted by the American Psychological Association or one of its allied publishers. tus, & Lindsay, 1995). One cognitive explana- ancy detection, proposed by Tousignant, Hall, This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. tion for the misinformation effect is suggested and Loftus (1986), suggests that individuals by the source-monitoring framework (Johnson, may be capable of accurately assessing the (in- Hashtroudi, & Lindsay, 1993), which claims )accuracy of postevent narratives containing that every memory, including memory for mis- misinformation without any cues other than the information, has a source, which is evaluated by content of the narrative. When individuals are the individual at the time of retrieval. Some- able to detect discrepancies between an event times misinformation is recalled instead of what and postevent misinformation, they are better was actually witnessed simply because the able to reject misinformation (Tousignant et al., source of the misinformation is confused as 1986). For example, increasing suggestive de- being from the original event, an error referred tails may actually inhibit children from devel- SOURCE CREDIBILITY, MISINFORMATION, AND MEMORY 3

oping images to false memories because they ceived misinformation experienced a high FOK are more likely to detect the discrepancies (Ot- when presented with a misinformation response gaar, Candel, Scoboria, & Merckelbach, 2010). option and therefore reported a high confidence In addition, Loftus (1979) found that providing judgment when choosing the misinformation re- individuals with blatant misinformation made sponse compared with individuals who chose the them more resistant to misinformation. In the misled response but never received it. The present present study, we examined whether increasing study aimed to address the relations between con- the proportion of misinformation to neutral in- fidence judgments and accuracy performance by formation in a postevent narrative would in- examining how confidence ratings differed among crease discrepancy detection by offering more different types of responses (i.e., correct, incor- opportunities to note discrepancies. To our rect, and misinformed responses) and how global knowledge, the present study is the first to in- performance estimates varied by actual perfor- vestigate whether individuals can correctly as- mance. sess the (in)accuracy of postevent narratives varying in the degree of misinformation without Overview of the Present Study any previous experience with the information source or any blatant credibility cues. We addressed the relations among misinfor- mation, perceived source credibility, and mem- Metacognition and Memory Performance ory accuracy. Participants watched a video of a mock crime and then received a misleading Metacognition may also play an important written narrative containing low (20%), me- role in explaining the misinformation effect. dium (50%), or high (80%) proportions of mis- Specifically, the metacognitive concept of feel- information. Participants then completed a ing of knowing (FOK) refers to a self-prediction memory test related to the video and answered regarding performance on a knowledge-based questions regarding the narrative’s credibility task, which may affect what an individual re- and their performance on the memory ques- ports when asked to recall an event. Previous tions. This between-subjects design allowed us research investigating the relation between an to test direct relations between amount of mis- individual’s FOK and actual performance on an information and memory accuracy, as well as exam demonstrates a tendency to overestimate the mediational effect of perceived credibility one’s performance and abilities (Falchikov & and relations with source monitoring accuracy. Boud, 1989). For example, Fischhoff, Slovic, We were also able to examine whether individ- and Lichtenstein (1977) found that when partic- uals are capable of accurately estimating their ipants were given general-knowledge questions performance and the effect of receiving differ- and subsequently asked to rate how confident ent quantities of misinformation on the calibra- they were in their responses, they were consis- tion of performance estimates and confidence tently overconfident in their responses. How- with respect to actual performance. ever, the majority of this research has focused We hypothesized that individuals exposed to on calibrating accuracy and confidence in terms larger proportions of misinformation would an- of knowledge-based tasks in learning contexts swer a smaller proportion of questions regard- (See Schwartz, 1994 for review). Less is known ing misinformation items correctly and a larger about whether individuals exhibit the same ten- proportion of those questions in line with the This document is copyrighted by the American Psychological Association or one of its allied publishers. dency to overestimate on tasks geared more misinformation compared with individuals ex- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. toward memory accuracy. posed to smaller proportions of misinformation. Additionally, some research has examined Our second hypothesis was that as misleading the differences between misinformed and con- information increased in proportion to nonmis- trol subjects on their accuracy-confidence cali- leading information, participants would per- bration (Tomes & Katz, 2000; Weingardt, Leo- ceive the source as less credible. Relatedly, we nesio, & Loftus, 1994). For example, Weingardt hypothesized that this change in perceived and colleagues found that individuals who were source credibility would mediate the relations misled endorsed greater confidence in their in- between misinformation exposure and memory correct responses compared with those individ- accuracy. Specifically, based on discrepancy uals who were not misled: Individuals who re- detection literature, we hypothesized that a de- 4 PENA, KLEMFUSS, LOFTUS, AND MINDTHOFF

crease in perceived credibility would result in a he also rummages through the owner’s personal dampening of the misinformation effect. belongings and steals some of their possessions, Fourth, based on the source monitoring view of such as a pair of earrings and a compact disk. misinformation resistance (Chambers & Zara- After viewing the video, participants were taken goza, 2001; Echterhoff et al., 2005), we hypoth- to a new survey page and were given a 12-min esized that perceived source credibility and filler task in which they were asked to answer source monitoring accuracy would be associ- trivia questions. Once the 12 min expired, they ated. Finally, we hypothesized that participants were automatically advanced to the next section would overestimate their performance on the of the study where they received further instruc- memory questions, especially if they were highly tions. inaccurate, based on past research showing indi- Misleading narrative. Participants were viduals’ tendency to overestimate their perfor- informed that a previous set of participants had mance, particularly if they are low performing written brief narratives about the robbery de- (Falchikov & Boud, 1989). picted in the video and that one of those narra- tives would be presented to them to refresh their Method memory. They were shown a photograph and basic demographic information about the al- Participants leged participant whose narrative they were reading. This “previous participant” was actu- The participants were 142 students at a large ally an artificial profile composed of a randomly southeastern university who were recruited via selected head shot chosen from a sample of the university’s psychology research participa- eight, which was retrieved via a publically tion system in exchange for course credit. Of available online database of faces. Participants these participants, six were excluded because of were also presented with artificially created de- a recording equipment malfunction, six because mographic information for the eight profiles they answered the -check question in- designed to loosely match the demographics of correctly, and three because they decided they the population from which the sample was did not want their data to be used. The final drawn: 21 year-old Caucasian male, 20 year-old sample of 127 participants was 69% female Caucasian male, 21 year-old Hispanic male, 20 (N ϭ 88) and representative of the community year-old Hispanic male, 21 year-old Caucasian from which they were drawn (65% Hispanic, female, 20 year-old Caucasian female, 21 year- 15% African American, 11% Caucasian, 4% old Hispanic female, and 20 year-old Hispanic Asian American, and 5% other). They ranged in female. The goal was to create believable pro- age from 18 to 39 years (M ϭ 21.21, SD ϭ files of information sources (alleged previous 3.28). participants) that participants could later evalu- ate for credibility. To gauge whether partici- Materials and Procedure pants believed that a previous participant had actually written the narrative, at the conclusion Participants completed all study procedures of the study they were asked, “Did you suspect via an online survey on individual computers in that the profile and narrative you read were a computer lab on campus. As many as 12 created by the research team instead of another participants were tested per session. Online con- participant? If so, what made you suspect?” This document is copyrighted by the American Psychological Association or one of its allied publishers. sent and all study procedures were administered Participants were randomly assigned to re- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. via the Qualtrics survey program and study par- ceive a narrative with a low (20%), medium ticipation lasted 60 to 80 min. (50%), or high (80%) proportion of misleading Mock crime video. After providing online information. Each narrative was composed of a consent, participants viewed a brief (six and a total of 40 sentences and so those in the 20% half minute) silent video of a mock crime, condition received a narrative with eight mis- which has been successfully used in previous leading sentences, the 50% condition received a related research (e.g., Takarangi, Parker, & narrative with 20 misleading sentences, and the Garry, 2006). The video depicts an electrician 80% condition received a narrative with 32 mis- who enters a house to fix various items such as leading sentences. The misleading sentences the oven and a light fixture, but while doing so were randomized so that the specific sentences SOURCE CREDIBILITY, MISINFORMATION, AND MEMORY 5

that contained misleading information varied which they could provide a misinformed re- across participants even within the same condi- sponse. We refer to these questions as “misin- tion. The pieces of misleading information were formation questions.” To account for varying changes made to details about objects seen in exposure to misinformation, we calculated the the video; information was not added. The non- proportions of correct, incorrect, and mislead misleading sentences were neutral to avoid responses to misinformation questions for each strengthening the participant’s memory trace participant. The denominator for each propor- for the target items. For example, a misleading tion score was the total number of misinforma- item was “He noticed the dresser was covered tion questions asked. We used these proportion with a brown cloth” and the neutral version of scores as our memory variables in all relevant that item was “He noticed the dresser was cov- analyses. For example, a participant in the 20% ered with a cloth.” Each of the 40 sentences was misinformation condition who answered six displayed to the participants one at a time. misinformation questions correctly would re- There was no time restriction per line so that the ceive a proportion correct score of 6/8 ϭ .75, participants could take however much time they whereas a participant in the 80% misinforma- needed to read each sentence. After reading the tion condition who similarly answered 6 misin- entire narrative, participants completed a 5-min formation questions correctly would receive a filler math test. After this, participants were proportion correct score of 6/32 ϭ .19. automatically advanced to a new page where Questionnaire. Following the questions they answered questions about the mock crime about the mock crime video, participants were video. given a 28-item questionnaire. The question- Memory questions. All participants were naire examined the participant’s metacognition asked the same set of 40 three-option forced- and perceived source credibility. Participants choice questions about the mock crime video were first asked questions concerning their cog- (e.g., Eric noticed that the dresser was covered nitive monitoring, which is the online monitor- with a cloth) in random order. For each memory ing of one’s own cognitive processes. Specifi- question, participants could choose the correct cally, participants were asked four questions answer, meaning, the option corresponding to about the strength of their memories (e.g., what was actually portrayed in the video (e.g., “How good is your memory for the video you navy), an incorrect answer that for some partic- just watched?”). All questions were answered ipants reflected a piece of misinformation pro- on a 5-point Likert scale with lower numbers vided in the narrative (e.g., brown), or an incor- indicating weaker memory strength and higher rect answer, corresponding to information that numbers indicating stronger memory strength. was not portrayed to any of the participants in These four items reached an acceptable level of the video or the narrative (e.g., yellow). The consistency (Cronbach’s ␣ϭ.73) and thus response choices were presented simultane- were averaged to create a memory strength vari- ously with the order randomized. For each item able. Participants were asked an additional three participants were subsequently asked how con- cognitive monitoring questions specifically fident they were of their answer, from one, aimed to gauge how well they thought they did meaning not very confident, to five, meaning on the memory questionnaire (e.g., “How many very confident. Finally, after each item they questions do you think you got wrong?”). Par- were also asked the source of their answer (i.e., ticipants’ answers to these cognitive monitoring This document is copyrighted by the American Psychological Association or one of its allied publishers. the video, the narrative, both, or neither). Par- questions were then directly compared to their This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. ticipants were also asked an attention-check actual performance. question to ensure that they actually read each Participants were then questioned about the sentence from the narrative presented to them. credibility of the (mis)information source (e.g., The attention-check question asked, “What is “How good was the quality of the narrative?” the answer?” to which they were instructed “How familiar is the other participant with the while reading the narrative to answer, “potato video?”). Specifically, participants answered chips.” eight questions concerning the perceived credi- Because participants were exposed to differ- bility of the narrative and narrator on a 5-point ing amounts of misinformation, they also dif- Likert scale with lower numbers indicating fered in the number of memory questions to lower credibility and higher numbers indicating 6 PENA, KLEMFUSS, LOFTUS, AND MINDTHOFF

higher credibility. The eight items were consis- probe the links between perceived source cred- tent (Cronbach’s ␣ϭ.83) and were averaged to ibility and source monitoring accuracy. Finally, create a perceived credibility variable. These we present analyses linking perceived and ac- items included helpfulness, quality, (in)accuracy, tual memory performance. narrator familiarity with the video, believability, honesty, and expected memory performance if Correct, Incorrect, and Misinformed presented with a different narrative. They were Responses by Misinformation Group also asked to indicate what percent of the narrative was accurate from 0% to 100%. Lastly, partici- Table 1 presents means and standard devia- pants were asked basic demographic questions. tions for the proportions of correct, incorrect, After participants finished the questionnaire, they and misled responses participants provided to were debriefed and were given the opportunity to misleading questions, by misinformation condi- rewatch the video to refresh their memory. tion. We found (a) significant differences be- tween conditions in the proportion of correct, 2 F(2, 124) ϭ 5.35, p ϭ .006, ␩p ϭ .079, and Results misled responses, F(2, 124) ϭ 7.77, p ϭ .001, ␩2 ϭ Preliminary Analyses p .111, provided, and (b) no significant condition effects on the proportion of incorrect Participants were roughly evenly distributed responses provided to misleading questions, ϭ ϭ ␩2 ϭ across study conditions (N ϭ 39 in the high F(2, 124) 0.02, p .984, p .000. Tukey’s misinformation condition, N ϭ 44 in the me- post hoc comparisons revealed that participants dium misinformation condition, N ϭ 44 in the in the 80% misinformation condition provided a low misinformation condition). There were no smaller proportion of correct responses and a significant differences in age, gender, ethnicity, higher proportion of misled responses to misin- or year in college between the misinformation formation items compared with participants in Ͻ conditions. The eight false participant profiles the 20% misinformation condition, ps .01. were approximately evenly distributed across We found no significant differences between the conditions such that a chi-square analysis re- 50% condition and either of the other condi- Ͼ vealed no significant differences in profile pre- tions, ps .05. sentation across conditions. Approximately one Source Credibility as a Mediator Between third of participants indicated that they sus- Misinformation Group and pected the profiles to be false (35%). Interest- ingly, of these, half suspected the profile solely Memory Accuracy because they noted inaccuracies in the narrative Our primary research question involved the allegedly provided by the person described in mediating role of perceived source credibility the false profile (17% of the total sample). Par- between receipt of misinformation and memory ticipants were retained in the sample regardless accuracy, which we have defined as the propor- of their responses to the skepticism question tion of misleading questions answered cor- given that these responses did not vary by con- rectly. In the first set of models, the independent dition, ␹2(6, N ϭ 127) ϭ 7.06, p ϭ .315, and were unrelated to the proportion of memory questions they answered correctly, F(3, 123) ϭ This document is copyrighted by the American Psychological Association or one of its allied publishers. .23, p ϭ .873. Table 1 This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. Next, we present analyses addressing our key Means and Standard Deviations for Proportions of research questions. First, we examine the effects Correct, Incorrect, and Misled Responses Provided of misinformation condition on proportions of to Misleading Items, by Misinformation Condition correct, incorrect, and misled responses to mis- Misinformation condition information questions. Second, we address our primary hypothesis regarding the mediating role Response type 80% 50% 20% ء(18.) 74. (16.) 66. ء(of perceived source credibility in the relations Correct .63 (.13 ءء(13.) 19. (14.) 26. ءء(between misinformation and memory perfor- Misled .30 (.13 mance via Andrew Hayes’ PROCESS tool for Incorrect .07 (.05) .07 (.08) .07 (.09) .p ϭ .001 ءء .p ϭ .006 ء SPSS (http://www.afhayes.com). Third, we SOURCE CREDIBILITY, MISINFORMATION, AND MEMORY 7

variable was misinformation condition dummy Table 2 coded to compare high versus low, in the sec- Estimated Marginal Means (EMMs) and Standard ond set of models, misinformation condition Errors of Proportions of Correct Responses to was dummy coded to compare medium versus Misinformation Questions by Condition Controlling low. We found a significant indirect effect of for, and Not Controlling for, Ratings of Credibility the high versus low misinformation condition and Estimates of the Percentage of the Narrative on the proportion of correct responses through That Was Incorrect ϭ ϭ perceived credibility, b .04, p .021, bias Control variables Control variables corrected and accelerated (BCa) 95% confi- included excluded dence interval (CI) [.01, .09], and through esti- Condition EMM SE EMM SE mated percentage of the narrative that was cor- rect, b ϭ .06, p ϭ .006, BCa 95% CI [.03, .11]. 80% .59 .02 .63 .03 A similar pattern of effects was evident when 50% .67 .02 .66 .02 we compared the medium and low misinforma- 20% .77 .02 .74 .02 tion conditions, except that only the indirect Note. An analysis of covariance with misinformation con- effect through estimated percentage of the nar- dition predicting proportion correct, including the control variables, was significant, F(1, 121) ϭ 15.59, p Ͻ .001, rative that was correct was statistically signifi- 2 ␩p ϭ .21. All differences between misinformation condi- cant, b ϭ .06, p ϭ .007, BCa 95% CI [.02, .10]. tions were significant, p ϭ .014 (80% vs. 50% condition), As hypothesized, overall, exposure to a higher p ϭ .001 (50% vs. 20% condition), p Ͻ .001 (80% vs. 20% proportion of misinformation was associated condition). Analysis of variance results, without the control variables, are presented in the text and in Table 1. Only the with a lower proportion of correct memory re- 80% and 20% misinformation conditions differed signifi- sponses to misinformation items, but this effect cantly, p ϭ .006. was dampened for those participants who were made particularly skeptical of the information source because of high levels of misinformation not. These results suggest that if the 80% mis- in the narrative (see Figure 1). The dampening information group had higher credibility esti- effect can also be seen in Table 2 in the contrast mates (similar to those in the 50% misinforma- in estimated marginal means and standard errors tion group), they would have performed with an when credibility estimates are controlled versus even lower proportion of correct responses to misleading questions on average, and if the 20% misinformation group had lower credibility es- timates they would have performed with a higher proportion of correct responses to mis- leading questions. Source-Monitoring and Memory Accuracy

Next, we examined whether skepticism about the credibility of the misinformation narrative was associated with source monitoring. We coded source responses for each memory ques- tion as accurate or inaccurate. For example, if a This document is copyrighted by the American Psychological Association or one of its allied publishers. participant selected a response in line with pre- This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. viously presented misinformation and then se- lected the narrative as the source of their response, the response would be coded as accurate source monitoring. Any other response (i.e., the video, Figure 1. Mediation model reflecting the direct effect of both the video and the narrative, or neither) would the misinformation condition on the proportion of correct be coded as inaccurate source monitoring. Source responses to misinformation questions and the mediating monitoring accuracy on individual items was av- roles of the variables reflecting participant perceptions of the narrative. The reported direct effects are independent of eraged to create a source monitoring accuracy the mediator variables. Unstandardized beta values are re- variable. As predicted, thinking that the narrative p Ͻ .001. was more credible and was composed of more ءءء .p Ͻ .01 ءء .p Ͻ .05 ء .ported 8 PENA, KLEMFUSS, LOFTUS, AND MINDTHOFF

correct information was associated with poorer items increased, r(100) ϭϪ.45, p Ͻ .001. source-monitoring accuracy, r(125) ϭϪ.41, p Ͻ There was no association between confidence .001 and r(124) ϭϪ.41, p Ͻ .001. and the proportion of misled responses to mis- leading items, r(100) ϭ .03, p ϭ .807. Metacognition and Memory Performance Discussion Participants were relatively accurate at mak- ing global estimates of their performance on the Previous research has demonstrated that peo- memory questions, except when they had been ple are able to disregard misinformation and misled. First, we compared participant esti- more carefully monitor their memories for ac- mates of the number of questions they answered curacy when they have reason to believe that the correctly to the actual number of questions for source of the misinformation lacks credibility which they selected the correct, incorrect, and (Hirst & Echterhoff, 2008; Koppel, Wohl, Me- misled response. Their estimates of the number ksin, & Hirst, 2014). However, in past research of questions they answered correctly increased participants are generally provided with cues with their actual number of correct responses, external to the narrative to help them assess r(124) ϭ .21, p ϭ .019, decreased with the source credibility, either before or after they number of incorrect responses, r(124) ϭϪ.22, have been provided with misinformation. These p ϭ .012, and had no relation with the number cues may not be true reflections of source ac- of misled responses, r(124) ϭ .02, p ϭ .860. curacy in real world contexts (Echterhoff et al., Next, we calculated a difference score by sub- 2005; Smith & Ellsworth, 1987). However, tracting the number of questions participants when people can detect discrepancies between thought they answered correctly from the num- their memory for an event and the misinforma- ber of questions they actually answered cor- tion presented, they are able to reject misinfor- rectly. A one-sample t test revealed that partic- mation (Tousignant et al., 1986). In the present ipants tended to overestimate the number of study, we manipulated the amount of postevent questions they answered correctly by about two misinformation participants received to exam- on average, (M ϭϪ2.06, SD ϭ 7.42), t(125) ϭ ine (a) the association between amount of mis- Ϫ3.12, p ϭ .002. The accuracy of participants’ information and susceptibility to misinforma- performance estimates tended to increase with tion, (b) whether increasing the proportion of actual performance accuracy such that the ab- misinformation to neutral information would solute difference between their actual perfor- impact perceived source credibility, (c) whether mance and estimated performance decreased as perceptions of source credibility mediated the the number of correct responses increased, misinformation-memory performance associa- r(124) ϭϪ.20, p ϭ .023. Next, we compared tion, (d) the relations between perceived source participants’ estimates of their memory strength credibility and source monitoring accuracy, and to the proportion of misleading items to which (e) whether participants were able to accurately they responded correctly. Mean memory assess their performance. Our results shed light strength ratings were approximately at the cen- on human memory processes, including contex- ter of the 7-point scale (M ϭ 3.58, SD ϭ .60) tual and individual difference predictors of re- and increased in line with their actual perfor- sistance to misinformation, and have important mance, r(125) ϭ .24, p ϭ .007. Finally, we implications for applied contexts such as in This document is copyrighted by the American Psychological Association or one of its allied publishers. assessed the accuracy of participants’ perfor- clinical settings. This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. mance estimates in terms of confidence in spe- First, we found, unsurprisingly, that exposure cific responses. An averaged confidence vari- to more misinformation led participants to an- able was created for participants who responded swer a lower proportion of misinformation to all 40 confidence questions (102 participants questions correctly and a higher proportion of in total). Higher average confidence estimates misinformation questions in line with the pre- (M ϭ 3.85, SD ϭ .55) were associated with a sented misinformation. The high rates of misin- larger proportion of correct memory responses formation may have burdened participants with to misleading items, r(100) ϭ .21, p ϭ .038. higher cognitive load as they struggled to mon- Conversely, confidence decreased as the pro- itor the high rates of misinformation. This cog- portion of incorrect responses to misleading nitive load may have made them more vulner- SOURCE CREDIBILITY, MISINFORMATION, AND MEMORY 9

able to the misinformation (Craik, Govoni, all participants rated their performance simi- Naveh-Benjamin, & Anderson, 1996; Magliano larly in terms of accuracy regardless of actual & Radvansky, 2001). accuracy. If this were the case, estimates would Critically, in line with our primary hypothe- appear more calibrated for highly accurate par- sis, an opposing pattern also emerged such that ticipants because on average, people estimated exposure to higher rates of misinformation led that they were highly accurate. Or it may be that participants to be more skeptical of the accuracy participants who were more resistant to misin- of the narrative, and this increased skepticism formation were also better able to estimate their led to an increase in resistance to misinforma- performance. The latter interpretation is in line tion. On average participants who received a with research demonstrating that students who narrative with 80% misinformation answered perform well on examinations tend to be more smaller proportions of questions about those attuned to their own performance (see Fal- misinformation items correctly (i.e., they were chikov & Boud, 1989, for a review). Examina- less accurate) than those who received 20%. tion of the present confidence results might shed However, within each condition participants some light on this. Specifically, subjective con- performed best if they reported being skeptical fidence ratings were positively related to cor- of the accuracy of the narrative. Participants rectly responding and negatively related to incor- who were presented with higher levels of misin- rectly responding. Thus, it appears that formation were most likely to be made skeptical, participants were at least somewhat attuned to and those who were made skeptical resisted a how well they remembered the information. In greater proportion of presented misinformation. line with previous research, participants appeared Skepticism, both in terms of perceived credibil- unaware when they had incorporated misleading ity and narrative accuracy, was also associated information both in terms of their performance with increased source monitoring accuracy. This estimates and subjective confidence ratings association may have emerged in line with a (Greene, Flynn, & Loftus, 1982; Loftus, Donders, source monitoring perspective (Koppel et al., Hoffman, & Schooler, 1989; Luna & Migueles, 2014), and in line with previous research using 2009). explicit warnings about source credibility (Echter- In summary, there appear to be two opposing hoff et al., 2005; Frost et al., 2002; Skagerberg & pathways linking misinformation to memory Wright, 2009), such that those participants who accuracy: a direct path between provision of were distrustful of the misinformation source misinformation and susceptibility to misinfor- more vigilantly monitored their memory to resist mation and an indirect path via perceptions of misinformation. The opposite pattern of results source credibility. On the one hand, receiving was also possible, such that participants who more high proportions of misinformation negatively vigilantly monitored the narrative for misinforma- impacted participants’ performance by increas- tion better detected discrepancies between the ing susceptibility to misinformation. On the video and narrative and thus reported that the other hand, when participants received more narrative was of lower credibility and accuracy. misinformation, they were, on average, more The directionality of this effect needs further ex- skeptical of the source of that misinformation, ploration in future research. and appropriately rated the narrative as contain- Participants also demonstrated successful ing fewer correct details and as being of lower metacognition in terms of estimating their cor- credibility. Critically, this skepticism about the This document is copyrighted by the American Psychological Association or one of its allied publishers. rect and incorrect responses, but not their mis- misinformation narrative was associated with This article is intended solely for the personal use of the individual user and is not to be disseminated broadly. led responses. While participants tended to increased source monitoring accuracy and re- slightly overestimate their accuracy, those who sulted in a significantly diminished misinforma- gave more correct and fewer incorrect responses tion effect. Thus, this research demonstrates that correctly rated themselves as being more accu- while provision of misinformation is undoubt- rate and as having stronger memories, and they edly detrimental to memory performance, indi- were more confident in their responses. Partic- viduals who are appropriately skeptical of the ipants who answered more memory questions accuracy of a misinformation source are par- correctly were also better calibrated in their tially protected from memory errors. performance estimates; however, the causal di- Our work also has implications for clinical rection of this relation is unclear. It may be that contexts. For example, recovered-memory ther- 10 PENA, KLEMFUSS, LOFTUS, AND MINDTHOFF

apeutic techniques (RMTs) are those in which Clifasefi, S. L., Garry, M., & Loftus, E. (2007). therapists attempt to extract clients’ purportedly Setting the record (or video camera) straight on “repressed” memories (Poole, Lindsay, Memon, memory: The video camera model of memory and & Bull, 1995). Researchers have revealed that other memory myths. Tall tales about the mind & brain: Separating fact from fiction (pp. 60–75). RMTs can involve suggesting event elements New York, NY: Oxford University Press. not previously mentioned by patients. More- Craik, F. I. M., Govoni, R., Naveh-Benjamin, M., & over, use of these types of techniques in re- Anderson, N. D. (1996). The effects of divided search settings increases the likelihood that in- attention on and retrieval processes in dividuals will incorporate false details into their human memory. Journal of Experimental Psychol- memories, or even unintentionally fabricate en- ogy: General, 125, 159–180. http://dx.doi.org/10 tire false events (e.g., Hyman, Husband, & Bill- .1037/0096-3445.125.2.159 ings, 1995; Loftus & Pickrell, 1995). Thus, Dodd, D. H., & Bradshaw, J. M. (1980). Leading RMT has been labeled a potentially harmful questions and memory: Pragmatic constraints. Journal of Verbal Learning and Verbal Behavior, psychological technique, both in terms of the 19, 695–704. http://dx.doi.org/10.1016/S0022- potential for memory distortion, and for the 5371(80)90379-5 mental health of clients (Lilienfeld, 2007). Echterhoff, G., Hirst, W., & Hussy, W. (2005). How However, according to a recent review article, eyewitnesses resist misinformation: Social post- these techniques still “flourish” (Lynn, Evans, warnings and the monitoring of memory charac- Laurence, & Lilienfeld, 2015). In contrast, em- teristics. Memory & Cognition, 33, 770–782. pirically supported therapies focus on allowing http://dx.doi.org/10.3758/BF03193073 patients to report and interpret events using their Falchikov, N., & Boud, D. (1989). Student self- own words, with therapists offering assistance assessment in higher education: A meta-analysis. Review of Educational Research, 59, in the deeper exploration and modification of 395–430. http://dx.doi.org/10.3102/00346543059004395 thoughts and feelings related to these experi- Fischhoff, B., Slovic, P., & Lichtenstein, S. (1977). ences, rather than the details of the remembered Knowing with certainty: The appropriateness of experiences themselves (Lane, Ryan, Nadel, & extreme confidence. Journal of Experimental Psy- Greenberg, 2015). 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