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How the Behavioral Immune System May Impact Responses to Violated Norms

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How the Behavioral Immune System May Impact Responses to Violated Norms University of Northern Iowa UNI ScholarWorks Dissertations and Theses @ UNI Student Work 2017 Sick of deviants: How the behavioral immune system may impact responses to violated norms Neal G. Pollock University of Northern Iowa Let us know how access to this document benefits ouy Copyright ©2017 Neal G. Pollock Follow this and additional works at: https://scholarworks.uni.edu/etd Part of the Applied Behavior Analysis Commons Recommended Citation Pollock, Neal G., "Sick of deviants: How the behavioral immune system may impact responses to violated norms" (2017). Dissertations and Theses @ UNI. 429. https://scholarworks.uni.edu/etd/429 This Open Access Thesis is brought to you for free and open access by the Student Work at UNI ScholarWorks. It has been accepted for inclusion in Dissertations and Theses @ UNI by an authorized administrator of UNI ScholarWorks. For more information, please contact [email protected]. SICK OF DEVIANTS: HOW THE BEHAVIORAL IMMUNE SYSTEM MAY IMPACT RESPONSES TO VIOLATED NORMS An Abstract of a Thesis Submitted In Partial Fulfillment of the Requirements for the Degree Master of Arts Neal G. Pollock University of Northern Iowa July, 2017 ABSTRACT In order to protect themselves from harmful pathogens, individuals have evolved a behavioral immune system (BIS) that is sensitive to disease cues (Schaller, 2006). At the cultural-level, there are variations in norms based on the prevalence of pathogens within a region (Schaller & Murray, 2008). Previous findings support the notion that the BIS promotes conformity (Murray & Schaller, 2012; Murray, Trudeau, & Schaller, 2011; Gelfand et al., 2011), as this produces an environment that is more protected against harmful pathogens. The current study attempted to provide experimental evidence for increased punishment for norm violations when the BIS was activated. Seventy-six participants were exposed to one of three photosets that were designed to elicit either BIS activation, general threat arousal, or a neutral affect. After viewing the photoset, participants took part in a fixed artificial group task in which fairness norms were violated. It was hypothesized that participants who were exposed to BIS activation would be more likely to reject unfair offers within that task. A main effect of offer fairness was found, where the more unfair an offer was, the more likely participants were to reject it. However, no significant interaction between prime and offer fairness emerged. This effect was neither moderated nor mediated by a measurement of perceived sensitivity to disease. Treating reaction time as the dependent variable, exploratory analyses revealed a similar main effect of offer fairness. Similarly, no significant interaction between prime and offer fairness emerged with reaction time as the dependent variable. Collapsing the BIS activation and general threat arousal groups did yield a moderately significant interaction between prime and offer fairness, suggesting that general threat arousal may play a role in responses to norm violation. Further exploratory findings and alternative explanations are discussed. SICK OF DEVIANTS: HOW THE BEHAVIORAL IMMUNE SYSTEM MAY IMPACT RESPONSES TO VIOLATED NORMS A Thesis Submitted In Partial Fulfillment of the Requirements for the Degree Master of Arts Neal G. Pollock University of Northern Iowa July, 2017 ii APPROVAL PAGE This study by: Neal G. Pollock Entitled: Sick of Deviants: How the Behavioral Immune System May Impact Responses to Violated Norms Has been approved as meeting the thesis requirement for the Degree of Master of Arts. ___________ _____________________________________________________ Date Dr. Nicholas Schwab, Chair, Thesis Committee ___________ _____________________________________________________ Date Dr. Helen C. Harton, Thesis Committee Member ___________ _____________________________________________________ Date Dr. Adam Butler, Thesis Committee Member ___________ _____________________________________________________ Date Dr. Patrick Pease, Interim Dean, Graduate College iii TABLE OF CONTENTS LIST OF TABLES ............................................................................................................. vi LIST OF FIGURES .......................................................................................................... vii CHAPTER 1: INTRODUCTION ........................................................................................1 Avoiding Potential Illness ..............................................................................................1 The Physiological Immune System: An Imperfect System ...........................................2 The Behavioral Immune System ....................................................................................4 Distinguishing Disease Threats from other Threats.................................................8 The Behavioral Immune System’s Relationship with Culture ......................................9 CHAPTER 2: CURRENT STUDY ..................................................................................15 Hypotheses ...................................................................................................................17 CHAPTER 3: METHOD ...................................................................................................19 Design ..........................................................................................................................19 Participants ...................................................................................................................19 Measures ......................................................................................................................20 Demographic Items ................................................................................................20 Perceived Vulnerability to Disease ........................................................................21 Social Dominance Orientation ...............................................................................22 Right Wing Authoritarianism ................................................................................22 Manipulation Check Items .....................................................................................22 Procedure .....................................................................................................................22 CHAPTER 4: RESULTS ...................................................................................................29 iv Manipulation Check .....................................................................................................29 Intensity..................................................................................................................30 Disgust ...................................................................................................................31 Discomfort .............................................................................................................32 Troubling................................................................................................................33 Outliers .........................................................................................................................34 Univariate Analyses .....................................................................................................36 Relationships Between Measures ................................................................................38 Main Findings ..............................................................................................................39 Exploratory Analyses ...................................................................................................42 Reaction Time ........................................................................................................42 Covariates ..............................................................................................................44 General Threat Arousal ..........................................................................................45 Threat Arousal Regression Models ........................................................................47 CHAPTER 5: DISCUSSION .............................................................................................50 General Discussion ......................................................................................................50 Limitations ...................................................................................................................56 Conclusion ...................................................................................................................57 REFERENCES ..................................................................................................................59 APPENDIX A: PERCEIVED VULNERABILITY TO DISEASE ...................................65 APPENDIX B: DISEASE PRIME GROUP EXAMPLE PICTURES ..............................67 APPENDIX C: GUN PRIME GROUP EXAMPLE PICTURES ......................................68 v APPENDIX D: NEUTRAL PRIME GROUP EXAMPLE PICTURES............................69 APPENDIX E: PICTURE RATING ITEMS ....................................................................70 APPENDIX F: ULTIMATUM GAME PROCESS ...........................................................71 APPENDIX G: EXPERIMENTER’S SCRIPT .................................................................72 vi LIST OF TABLES TABLE PAGE 1 Demographics ........................................................................................................20
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