Adults, Not Kids, Make Worse Witnesses to Emotional Events

Newswise — If your legal fate is resting in the hands of a key adult witness to an emotional event, don’t rest easy.

New research by two Cornell University professors has shown that emotions, particularly those provoked by negative events, can trigger inaccurate memories – and the effect is worse, not better, when the witness is an adult.

The findings, set to be published this fall in the peer-reviewed Journal of Experimental Child Psychology and available online now, contradict prevailing legal and psychological thinking and have implications for the criminal justice system, said human development professors Valerie Reyna and Charles Brainerd.

The researchers, who also co-authored the 2005 book “The Science of False Memory,” previously demonstrated that adults attach far more meaning to events than children do. Now, working with colleagues at the University of Leicester and the University of North Florida, the pair conducted experiments at Cornell's Memory and Neuroscience Laboratory. The works shows that experiences that stimulate negative emotions are very bad for the accuracy of children's memories, but even worse for the accuracy of adults.

“We found something different than what leading theories of emotional memory in adults say,” Brainerd said. “By manipulating the emotional content of word lists, we found that materials that had negative emotional content in fact produced the highest levels of false memory.”

Children ages 7 and 11, and young adults ages 18 to 23, were shown lists of closely related emotional words – such as “pain,” “cut,” “ouch,” “cry” and “injury.” In each list some related words – such as “hurt” – were left out. When asked to recognize words from the list, respondents would often mistakenly remember “hurt” as one of the words. These mistakes allowed researchers to determine the level of emotion-induced false memory at each age.

The implications of the findings are profound for the U.S. legal system.

“In the great preponderance of legal cases, the only evidence that’s determinative is what people say happened,” said Brainerd, who directs Cornell’s psychology and law program. “That’s it. So the question of the conditions under which your memory of events is distorted is the most fundamental question about the reliability of evidence – because it is most of the evidence.”

Brainerd continued. “In the law, you’re dealing with events that are emotional. So the question of whether or not the emotional content of experiences that you’re trying to remember screws up your memory is a really big question.”

The National Science Foundation supported this research.