Roy F. Baumeister*, Jean M. Twenge** and Christopher K. Nuss***
*Case Western Reserve University, **San Diego State University, ***University of Minnesota
Received June 7, 2001 Revision received March 18, 2002 Accepted April 1, 2002
Three studies examined the effects of randomly assignedmessages of social exclusion. In all 3 studies, significant and large decrements in intelligent thought (including IQ and Graduate Record Examination test performance) were found among people told they were likely to end up alone in life. The decline in cognitive performance was found in complex cognitive tasks such as effortful logic and reasoning; simple information processing remained intactdespite the social exclusion. The effects were specific to social exclusion, as participants who received predictions of future nonsocial misfortunes (accidents and injuries) performed well on the cognitive tests. The cognitive impairments appeared to involve reductions in both speed (effort) and accuracy. The effect was not mediated by mood.
The two most important and powerful adaptations of thehuman race are intelligence and social structure. Human intelligence, based on a large and powerful brain, is far superior to what has been observed in almost every other species. Human social organization is likewise more complex and flexible than what has been observed elsewhere. Barchas (1986) has proposed that the small social group is the single most important adaptation of human beings,more important even than intelligence, although certainly other theorists would argue that intelligence deserves priority. In any case, it is clear that the human capacity for intelligent, complex thought has enabled people to solve problems and master their environment to an unprecedented extent, and human social groups have likewise contributed immensely to cultural and technological progress,safety and comfort, and individual well-being. The present investigation was designed to investigate the possible link between social belongingness and intelligent thought. Specifically, we explored the impact of social exclusion on cognitive processes. We led participants to believe that they would be alone in later life, and we measured the impact of this message on cognitive functioning. Practicaland ethical constraints prevented us from studying long-term deprivation and potentially permanent changes in intelligence, but we were able to study shortRoy F. Baumeister, Department of Psychology, Case Western term effects of social exclusion on mental Reserve University; Jean M. Twenge, Department of Psychology, performance. Competing predictions could San Diego State University; ChristopherK. Nuss, Department of be generated. From a simple evolutionary Psychology, University of Minnesota. Correspondence concerning this article should be addressed to perspective, one might assume that it would Roy F. Baumeister, Department of Psychology, Case Western Reserve be highly adaptive for intelligent functioning to increase among people who expect to University, Cleveland, Ohio 44106-7123, orto Jean M. Twenge, Department of Psychology, San Diego State University, 5500 be excluded from social groups. There is, Campanile Drive, San Diego, California 92182-4611. E-mail: rfb2@ after all, some overlap (and hence potential po.cwru.edu, email@example.com, or firstname.lastname@example.org redundancy) in the benefits to be gained from
Journal of Personality and Social Psychology 2002, Vol. 83, No. 4,817–827 © 2002 by the American Psychological Association, Inc.
Effects of Social Exclusion on Cognitive Processes: Anticipated Aloneness Reduces Intelligent Thought
social group membership and intelligent thought. To survive, people need to make effective decisions, avoid danger, resolve problems, cope with misfortunes, and obtain life-sustaining resources. Belonging to a group can...