, Volume 33, Issue 5, pp 770-782

How eyewitnesses resist misinformation: Social postwarnings and the monitoring of memory characteristics


Previous findings have been equivocal as to whether the postevent misinformation effect on eyewitness memory is reduced by warnings presentedafter the misinformation (postwarnings). In the present research, social postwarnings, which characterize the postevent source as a low-credibility individual, diminished the misinformation effect in both cued recall and recognition tests. Discrediting the source as being either untrustworthy or incompetent was effective (Experiment 1). Also, postwarned participants rated reality characteristics of their memories more accurately than did participants receiving no or high-credibility information about the postevent source (Experiment 2). A social postwarning yielded the same results as an explicit source-monitoring appeal and led to longer response times for postevent items, relative to a no-warning condition (Experiments 3 and 4). The findings suggest that the reduced misinformation effect was due to more thorough monitoring of memory characteristics by postwarned participants, rather than to a stricter response criterion or to enhanced event memory.

Experiments 1 and 3 were conducted as part of a doctoral dissertation at the Graduate Faculty of Political and Social Science of the New School for Social Research. The dissertation research was supported by a German Academic Exchange Service (DAAD) fellowship to the first author. Experiment 4 was supported by Grant HU 372/5-I from the German Science Foundation (Deutsche Forschungsgemeinschaft) to the third author. Hartmut Blank, Bertram Gawronski, Norbert Groeben, and Birgit Neumann provided valuable comments on earlier drafts. Gratitude is extended to Stephan Groll for his assistance in conducting and analyzing Experiment 2.