The Consequences of Vicarious Intergroup Exclusion

Intergroup violence and conflict have devastating consequences for individuals and societies alike. Across five experimental studies (N = 1,870) conducted cross-culturally using a multimethod approach integrating behavioural and neuroscientific research methods, this thesis tested the consequences of vicarious intergroup exclusion, exclusion that concerns ingroup members, but that does not directly target the individual. The results indicate that the experimental manipulation of vicarious intergroup exclusion is experienced on the personal level, increasing perceived personal exclusion. At least under some conditions, it impairs mood (Studies 1-4), increases intergroup hostility (Studies 1, 4) and aggression (Study 3, 4), and threatens fundamental psychological needs (Study 1b). The increased aggression following the ingroup’s observed exclusion may target not only members of the excluding outgroup, but members of ‘innocent’ outgroups as well (Study 3). The results further indicate that group status and power do not influence the effects of exclusion on mood, hostility, and aggression (Study 1b). Antagonistic, but not secure ingroup positivity was related to a greater increase in hostility following vicarious intergroup exclusion (Study 3). Vicarious intergroup exclusion affected hostility (Studies 1, 3, 4) and aggression (Studies 1b, 4) indirectly, via impaired mood, but not via threatened needs (Study 1b). Based on the underlying role of mood impairment, we tested interventions aiming to reduce the negative affect, intergroup hostility, and aggression related to vicarious intergroup exclusion by fortifying emotion regulation (Studies 2, 4). However, the interventions were unsuccessful in achieving these aims. Not all studies replicated all findings, so we summarized the main results observed throughout the thesis in meta-analyses. The meta-analytic summaries indicate that the
intergroup settings used to create the experimental manipulation of vicarious intergroup exclusion (e.g., existing vs. minimal groups) influenced its effects. These findings, their implications, and future research directions are discussed in detail.