Emotional ‘hangovers’ influence future memories

The research suggests that experiencing an emotional event – such as winning the U.S. Open – can influence how memories are made afterward. Keystone

Researchers have known for some time that people remember emotional life events better than non-emotional ones. But a new study shows that emotional experiences actually affect how we will remember future events, too.

A simple experiment designed by researchers at the University of Geneva and New York University has revealed that emotional “hangovers” of life events marked by strong feelings lead to better memories of subsequent events – however unconnected or ordinary they may be. The results were published in December in the journal Nature Neuroscience.

To obtain their results, the researchers divided study participants into two groups. The first group viewed a series of images with strong emotional content, followed by a series of non-emotional images 10-30 minutes later. In the second group, the image-viewing order was reversed, with the non-emotional scenes being shown first. Functional magnetic resonance imaging (fMRI) was used to measure subjects’ skin conductivity and brain activity while they viewed the images.

Six hours later, all the subjects were given a memory test. The results showed that the subjects who viewed the series of emotional images first had better long-term recall of the non-emotional images than the subjects who viewed the emotional series second.

In other words, the brain state triggered by viewing the emotional images led to a “hangover” effect that lingered during the formation of memories about the non-emotional images. And sure enough, the fMRI measurements showed that same brain activity patterns associated with emotional memory formation also occurred later, while memories of the non-emotional memories were being produced.

“This study will allow us to shed light on certain essential aspects of the mechanisms governing our memories,” said study co-author Ulrike Rimmele, a postdoctoral researcher in the Department of Basic NeurosciencesExternal link in the Faculty of Medicine at the University of Geneva Campus Biotech.

“This could be used not only to propose new methods of education and training, but also to decode and treat the nature of certain psychological disorders, such as anxiety or PTSD [posttraumatic stress disorder],” she said in a statement.