Effects of collaborative recall: Denying true information is as powerful as suggesting misinformation

Using a social contagion paradigm, we compared the corruptive effects on memory of two types of post-event misinformation: Suggesting incorrect details and denying correct details. Together with a confederate, undergraduate participants (n =90) watched complex scenes. Next, participant and confederate took turns in recalling scene details. In one condition, the confederate suggested incorrect details, whereas in the other condition the confederate denied true details recalled by the participant. Finally, participants were given a second free recall test in the absence of the confederate. Denying correct details appeared to be as powerful as suggesting incorrect information, with 72% of the participants omitting previously mentioned, but confederate-denied, details from their free recalls and 52% incorporating incorrect details in their free recall. Also, these participants scored higher on the Gudjonsson Compliance Scale than those who were not misled by the suggestions of the confederate.