題目： Two types of coalitional psychology: Exploring distinct mechanisms for intergroup bias
氏名： 出馬圭世
担当教官： 結城雅樹
I explored the nature of intergroup bias from the evolutionary perspective in two studies.While terror management theory (i.e., Greenberg et al., 1997) has claimed and showed that only the contemplation of one’s own death leads to increased intergroup bias, Navarrete and colleagues (Navarrete et al., 2004; 2005; Navarrete, 2005) have recently proposed the theory of coalitional psychology and showed that not only mortality-salience, but also priming of adaptive challenges that humans experience but that can be remedied through coalitional support from others lead to increased intergroup bias.In the present study, I elaborated this idea further by incorporating Brewer’s (1999; 2001) contention that positive attitudes toward ingroups have independent and more fundamental function from the negative attitudes toward outgroups.It is argued that while favorable attitudes toward ingroups always play a role in enhancing coordination and cooperation within ingroups, hostility toward outgroups should emerge only when there is threat from outgroups.Therefore, it is predicted that priming of adaptive challenges in which an individual need coalitional support would increase only positive attitudes toward ingroups, while priming of the intergroup conflict situation, one of adaptive challenges where the existence of outgroup is relevant, would increase both positive feelings toward ingroups and hostility toward outgroups.
In two experiments, I, in addition to three experimental conditions in Navarrete et al. (2004; 2005), added the intergroup conflict-salience condition in which the threat from an outgroup is primed, was added.Therefore, there were four conditions in the current research; 1) mortality-salience (MS), 2) house building-salience (HB), 3) intergroup conflict-salience (IC), and 4) control.In Study 1, Japanese undergraduate participants rated two essays (positive and negative) toward Japan (ingroup) and two essays toward the United States (outgroup).In Study 2, three different ingroup-outgroup relations were employed, and each participant evaluated one’s own country (Japan), class, and student circle as ingroups as well as three corresponding outgroups on trait adjectives.
In Study 1, although there was no significant increase of intergroup bias in three experimental prime conditions compared to the control condition, the moderating effect of trait self-esteem was found.In the MS condition, high trait self-esteem individuals were significantly more likely to show increased intergroup bias following the priming than low self-esteem, while there was no difference between high and low self-esteem individuals in the control condition, the result consistent with Baldwin and Wesley (1996).Although the effect of self-esteem in HB and IC conditions was not significant, the basic patterns were similar to that in the MS condition.However, contrary to the prediction, this increase of intergroup bias in high self-esteem individuals was in large part due to the decrease of outgroup evaluation, not the increase of ingroup evaluation.
In Study 2, in the country evaluation, although the effects were not significant, the moderating effect of self-esteem was similar to Study 1 (except for the IC condition), and it was high self-esteem individuals in HB and MS conditions who showed increased intergroup bias relative to the control.In the class evaluation, successfully replicating Navarrete (2005), the significant increase of intergroup bias following the HB priming was found, but there was virtually no increase of intergroup bias in IC and MS conditions compared to the control.However, separate analyses for ingroup and outgroup evaluations showed that, contrary to the prediction, this increase of intergroup bias in the HB condition was in large part due to the decrease of outgroup evaluation.In the student circle evaluation, there were virtually no differences in level of intergroup bias between the control and each experimental condition.
Taken together, the results of the present research were not consistent with the predictions. The experimental primes largely failed to elicit increased intergroup bias, and even when the increased intergroup bias was observed in some conditions, it was all due to the decrease of outgroup evaluation, and throughout two studies, there was almost no influence of experimental manipulations on ingroup evaluations.Furthermore, if anything, participants in the IC condition tended to decrease both ingroup and outgroup evaluations, and the possible reason for this effect was discussed.Also, the results concerning the moderating effect of participants’ trait self-esteem was consistent with Baldwin & Wesley (1996), but totally opposite to Harmone-Jones et al.’s (1997) finding.Theoretical backgrounds on this moderating effect of self-esteem were discussed from the perspectives of terror management theory and sociometer theory of self-esteem.