New research from the University of Toronto is revealing information about the role that your eyes play in recalling memories. The U of T-affiliated Baycrest Health Sciences research team used simultaneous brain scanning and eye tracking technology to learn that when people recall images they’ve previously viewed, their eyes move in the same way as when they first saw the image, helping the brain to reconstruct the memory.

“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,” says Dr. Bradley Buchsbaum, senior author on the study, scientist at Baycrest’s Rotman Research Institute (RRI) and psychology professor at the University of Toronto.

Individuals aged 20 to 28 were shown 14 images for only a few seconds each. They were then asked to recall as many details of the images as they can remember, while their brain scans and eye movements were analyzed. The participants were then encouraged to envision the original picture inside a blank rectangle.

Using a mathematical algorithm, the researchers learned that the brain and eye activity of the participants when recalling images matched a “condensed” version of how they originally captured the memory.

“This is likely because when we recall a memory, it’s a condensed version of the original experience. For example, if a marriage proposal took two minutes, when we picture this memory in our head, we re-experience it in a much shorter timeframe,” says Dr. Buchsbaum. “The eye movements are like a short-hand code that your brain runs through to trigger the memory.”

The next step in the research, according to Dr. Buchsbaum, is to determine whether the eye movements lead to the brain “reactivating” the memory, or vice versa. They hope that this research could lead to new avenues of diagnosing neurodegenerative illnesses.