Eyes help remember images, long after first seen

When you close your eyes and visualize an important moment from the past, your brain may use the same eye movement patterns to reconstruct images long after you’ve originally seen them. It may seem like science fiction, but a study published in Cerebral Cortex found evidence of the phenomena.

"There's a theory that when you remember something, it's like the brain is putting together a puzzle and reconstructing the experience of that moment from separate parts," said senior author Bradley Buchsbaum, MD, with Baycrest Centre for Geriatric Care’s Rotman Research Institute (RRI) in a press release. "The pattern of eye movements is like the blueprint that the brain uses to piece different parts of the memory together so that we experience it as a whole."

A team of Canadian researchers used an algorithm to analyze fMRI brain scans and eye movements of 16 adults, ages 20 to 28. Participants were shown a set of 14 different images for a few seconds each and asked to remember as many details as possible.

Soon after, an empty rectangular box flashed on the screen prompting individuals to mentally recall the images they were shown. Imaging and eye tracking technology captured the brain activity and eye movement patterns of the participants while they memorized and then remembered the pictures.

Analyzing eye movement and brain activity allowed the team to accurately identify which image a person was remembering during the task.

Effectively this demonstrated the eyes move the same way when a mental image is first created as they do when recalling that original event or image, termed neural reactivation, and the brain shows a strikingly similar pattern of activity.

“Neural reactivation correlated positively with fixation reinstatement, meaning that image-specific eye movements accompanied image-specific patterns of brain activity during visualization,” wrote corresponding author Michael B. Bone and colleagues. “These findings support the conception of mental imagery as a simulation of perception and provide evidence consistent with the supportive role of eye movement in neural reactivation.”