Disruptive effects of disconfirmed expectancies about crowding.

Utilized a 2 (high vs low room density)?×?2 (forewarning of a crowded room vs no forewarning)?×?2 (simple vs complex task) design to examine the effects of anticipation of crowding on task performance of 80 undergraduates. More tasks were attempted and efficiency was higher when expectancies about the crowd were confirmed. Ss not told to anticipate a crowd who actually worked under high density and Ss warned about a crowd that did not materialize performed most poorly. These differences were largest for the complex task. The results of A. Baum and C. I. Greenberg (see PA, Vol 56:2328) were replicated with the performance data. Perceptions of the experimental room also differed as a function of anticipation, but failure to obtain a Crowding?×?Anticipation interaction did not support their hypothesis that anticipating a crowd induces perceptions identical to those obtained under actual crowding. Results are discussed in terms of disconfirmed expectancies being disruptive of performance, particularly complex task performance. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)