Expectancies and memory for an emotional film fragment: a placebo study.

This study investigated whether positive ("memory-enhancing") and negative ("memory-impairing") placebos may enhance and undermine, respectively, memory of a film fragment. After watching an emotional film fragment, participants were assigned to a "memory-enhancing" placebo group (n = 30), control group (n = 30), or "memory-impairing" placebo group (n = 30). Only participants who believed in the placebo effect were included in the analyses. In the positive placebo group, memory for the film fragment was better than that of participants who received negative placebos or control participants. Participants in the negative placebo group made more distortion errors than participants in the positive placebo or control group. Our findings show that people's expectancies about their memory may affect their memory performance. These results may have implications for both clinical practice and the legal domain.