Misinformation can alter memories of stressful events

More than half of subjects shown a misleading photograph shortly after a highly stressful event later misidentified a key individual involved in that event. This result is one of many in a new study that suggests memories of recently experienced events are more vulnerable to modification than generally thought. The article appears online ahead of publication in the International Journal of Law and Psychiatry.

"This is the first study to demonstrate that false memory inducing methods do indeed apply to recently experienced events and are not limited to remote experiences from childhood," said C. A. Morgan III, MD, associate clinical professor of psychiatry at the Yale School of Medicine and the study's lead author.

This "misinformation effect" appears to be the case even in individuals whose level of training and experience might be thought to render them relatively immune to such influences. The effect appears to operate largely outside a person’s awareness.

Participants in this study included more than 850 active duty military personnel confined in the mock POW camp phase of Survival School training. An important component of this highly stressful training is a mock interrogation. Following the interrogation, some participants were exposed to misinformation about their experience embedded in questionnaires, misleading photographs, or altered videos.

The majority of study participants were correct when describing characteristics about their interrogator that one might observe from a distance including race, gender, height and build. But, a majority of those same participants were incorrect when describing other characteristics including facial hair, eye color, or shape of face.

"Many people, including judges, juries, and law enforcement agents believe that memories for highly stressful events are remembered accurately and are not vulnerable to alteration," Morgan said. "Based on this study, one might anticipate that the use of leading questions, or exposing witnesses to photographs, statements, or media reports may significantly alter subsequent recollections."

Steven Southwick, the Glenn H. Greenberg Professor of Psychiatry, Post-Traumatic Stress Disorder, and Resilience and professor in the Child Study Center is the other Yale-affiliated author of the study.

Read the study .

This article was submitted by Shane Seger on December 14, 2012.