Experimental group threat causally reduces perceived complexity of one’s own group memberships.

Evidence

In two experimental studies involving Israeli student samples, Roccas and Brewer (2002) manipulated threat perceptions by asking half the sample to respond to a set of items gauging the perceived accessibility of unconventional weapons in a possible future war with Iraq (the high threat condition), and compared these with the other half of the sample who responded to a set of items on nature-related issues (the low threat condition). The studies examined the effects of the threat manipulation on similarity complexity (Study 1) and overlap complexity (Study 2), as well as the effects of threat on stress-related mood. Both studies corroborated their predictions, namely that high threat would be associated with more simplified, less complex multiple in-group perceptions, as well as with higher stress-related mood. Threat perceptions also yielded significant effects on both types of social identity complexity over and above the effects of mood-related stress. Interestingly, the effect of threat on social identity complexity failed to reach statistical significance when the category implicated in the threat manipulation (“Israeli”) was removed from the social identity complexity measures, supporting the view that threat heightens the salience of the threatened category relative to the other categories the individual belongs to. — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 574

Categorization

• XREF: Provides the causal-experimental warrant for the reader’s prejudice thread: threat narrows identity complexity, tying directly to mechanisms behind scapegoating and outgroup hostility. — connects to: Distinctiveness threat shifts behavior more than judgment, though its effect size is tiny. — Blake M. Riek, Eric W. Mania, and Samuel L. Gaertner, Intergroup Threat and Outgroup…, 64
• QUESTION: Whether stress-related mood is a mediator or only a correlate of threat’s effect on complexity stays ambiguous here; worth chasing whether later work disentangles the pathway.
• corroborated: 2 independent passages support this claim — Roderick M. Kramer, Geoffrey J. Leonardelli, Robert W. Livingston, Social Cognition, Social Identity, and…, 574