Emotion may improve ability to recall memories, study finds



On any given day, at any given moment, a memory is formed. Whether it’s a job promotion, a meaningful game or the start of a new relationship, it’s a moment that the brain can later recall. However, according to a New York University study, as time goes on, recovered memories can be altered by the emotions tied to it.

“We’re continuously monitoring our environment, and, in the process, accumulating countless details,” Joseph Dunsmoor, lead study author and post-doctoral fellow at NYU said. “We forget most of these details, but these new findings suggest that meaningful or emotional events can selectively preserve memory for previously encountered information that seemed insignificant at the time,” he said.

Study author Lila Davachi told that the process is similar to the way we watch detective movies.             

“You’re taking in all the details from moment to moment, but you don’t yet know who did it. Then sometime during the ending of the movie you get the answer, and everything you’ve been watching for the past hour comes into focus. That aha moment where finally everything fits into place can change what you remember,” Davachi, a professor of psychology and neural science told

“Details that aren’t relevant anymore, you may drop,” she said.

For the study, the research team asked 119 men and women to identify a series of images of animals and tools. Five minutes later, all participants were fixed with electrode wires on one wrist. Half of the group received an random, uncomfortable shock when they saw an animal, and the other was shocked randomly when they saw a tool.  The shock was meant to link the images with an emtion—anxiety— during the learning process.

Participants were then tested immediately or after a delay to see how many images they remembered from both rounds of identifying.

Researchers found that participants were better able to recall the images paired with the electric shock than the images not paired with a shock.

They also observed that the shocks created emotional learning that influenced the memory of the images shown before the shocks were induced. For example, the test group who received a shock while viewing tool images during round two, was better able to recall tool images seen in round one than they were any of the animal images.

“What it does tell us is that making things meaningful in any particular way is going to be a good way to strengthen memory,” Davachi said.

In early treatment for Alzheimer’s and dementia sufferers, therapists may provide patients with some type of training that uses a reward, Davachi said. For example, a patient is asked to look at pictures of family members that they may be starting to have difficulty remembering. The therapist reiterates to the patient about the reward for remembering the pictures— knowing their loved ones by sight without struggling with memory. This can help build and solidify their memory in identifying the family member.

The research team agreed that the study’s results prove the memory system is highly adaptive and more complex than previously thought.

Every time you encounter anything in the world, it has the ability to improve your memory recall, Davachi said.

The study was published Wednesday in the journal Nature.