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Sleeper Effect

  1. G. Tarcan Kumkale

Published Online: 30 JAN 2010

DOI: 10.1002/9780470479216.corpsy0882

Corsini Encyclopedia of Psychology

Corsini Encyclopedia of Psychology

How to Cite

Kumkale, G. T. 2010. Sleeper Effect. Corsini Encyclopedia of Psychology. 1–2.

Author Information

  1. Koç University, Istanbul, Turkey

Publication History

  1. Published Online: 30 JAN 2010


The sleeper effect refers to a delayed increase in the impact of a persuasive message. It is said to occur when the delayed effect of the message is greater than its immediate effect. For instance, recipients of a message may disagree with the message and show little or no attitude change in response. Over time, however, attitudes may shift in the direction of advocacy, especially if the recipients remember the message well but forget the reason for discounting it in the first place. In everyday life, people receive hundreds of messages on a given day. Therefore, remembering the message, its source, and the features of the original learning context becomes quite difficult. Consequently, the sleeper effect should be widely observed in everyday life.


  • delayed recall;
  • memory