A simple technique for improving eye-witness memory

Thanks to the foibles of human memory, eye-witness evidence is notoriously unreliable. One attempt to help the situation was the Cognitive Interview (pdf), conceived by psychologists in the 1980s. This involves strategies such as conducting the interview in a situation that matches the original crime context as closely as possible, and asking witnesses to remember events from multiple perspectives. Although highly effective, the Cognitive Interview can be impractical and it often goes unused. Now Annelies Vredeveldt and Steven Penrod have tested a far simpler technique for improving eye-witness memory - getting them to close their eyes. Lab research has already shown that this can be beneficial. Vredeveldt and Penrod took the technique out on the streets to see if it works there too.

Ninety-six undergrads signed up for what they thought was a study into "social interactions". In groups of up to four, they met two female researchers on a New York street corner. Shortly after the participants' arrival the two women started arguing and insulting each other. The altercation ended with one of the women knocking the other woman's papers to the ground and storming off.

After they'd witnessed the public spat, the participants were led away either to another street location or the psychology lab, both being five minutes' walk. Here they were asked to recall everything they could about the event, and then they were asked a series of questions about what happened. Half the participants were instructed to close their eyes during the recall and the interview (they weren't told why); the other half were not. The researchers ensured each of the staged arguments was caught on film so that the participants' answers could be checked for accuracy.

Overall, participants who closed their eyes recalled 37.6 per cent more useful visual information about the argument, and, in questioning, they produced 23.8 per cent more correct answers coded as having high detail. The advantage of having closed eyes was most pronounced for participants who were quizzed inside. This supports the idea that the technique works by helping participants to create the original context in their mind's eye. If it worked by helping reduce distraction, you'd think it would have had more of a benefit out on the street.

"From an applied perspective, the findings were promising," Vredeveldt and Penrod said. "In free recall, the effect size of the eye-closure effect for witnesses interviewed inside (d=.88) approached the effect size obtained with the Cognitive Interview.

"Given that the eye-closure instruction requires no training or additional interview time, it could prove to be a useful alternative [to the Cognitive Interview]," they added.

_________________________________

Annelies Vredeveldt, and Steven D. Penrod (2012). Eye-closure improves memory for a witnessed event under naturalistic conditions. Psychology, Crime and Law DOI: 10.1080/1068316X.2012.700313

Post written by Christian Jarrett for the BPS Research Digest.