Peer Contagion of Aggression and Health Risk Behavior Among Adolescent Males: An Experimental Investigation of Effects on Public Conduct and Private Attitudes


  • This work was supported in part by grants (awarded to both authors) from the Society for the Psychological Study of Social Issues and from the Yale University Faculty Fund.
    We extend our gratitude to Annie Fairlie, Daryn David, Victoria Brescoll, Allison Master, and Gregory Walton for their assistance with data collection, to Patti Brzustoski, Allison Master, and Nancy Apfel for helpful comments on earlier drafts, and to the adolescents and their families who participated in this project. We are also indebted to Blair Jarvis for helping to program the computer protocol used in the study presented here.

concerning this article should be addressed to Geoffrey Cohen, Department of Psychology, University of Colorado, Muenzinger Building, Boulder, CO 80309-0345, or to Mitchell J. Prinstein, Department of Psychology, University of North Carolina at Chapel Hill, Davie Hall, Campus Box 3270, Chapel Hill, North Carolina 27516-3270. Electronic mail may be sent to,, or


Peer contagion of adolescent males' aggressive/health risk behaviors was examined using a computerized “chat room” experimental paradigm. Forty-three 11th-grade White adolescents (16–17 years old) were led to believe that they were interacting with other students (i.e., “e-confederates”), who endorsed aggressive/health risk behaviors and whose ostensible peer status was experimentally manipulated. Adolescents displayed greater public conformity, more internalization of aggressive/health risk attitudes, and a higher frequency of actual exclusionary behavior when the e-confederates were high in peer status than low. Participants' level of social anxiety moderated peer contagion. Nonsocially anxious participants conformed only to high-status peers, whereas socially anxious participants were equally influenced by low- and high-status peers. The role of status-maintenance motivations in aggression and risk behavior, and implications for preventive intervention, are discussed.