By Marcia-Ruth Ndege ‘21
For the first time in history, researchers have established a direct connection between eye movement patterns and brain activity. Using brain imaging technology, scientists from the Baycrest Rotman Research Institute (RRI) found evidence that the brain uses eye movements to help recreate vivid moments. Dr. Bradley Buchsbaum, a scientist at RRI and a professor of psychology at the University of Toronto, was the senior author of the study.
The study consisted of 16 adults between the ages of 20 and 28. Participants were exposed to 14 distinguishable images, each for a few seconds, while their eye movements and brain activity were recorded by an eye-tracking and brain imaging device. They were then asked to revisualize the images on a screen while being monitored by the same device. Researchers then used a mathematical algorithm to analyze the brain scans from the first time subjects saw the image and from the moments of revisualization. Results showed that participants made the same eye movement patterns while viewing and while revisualizing the images; in addition, patterns in brain activity were analogous. In fact, the researchers were able to identify which image a person was remembering solely based on his or her patterns of eye movement. While the patterns of eye movement and brain activity appeared to be compressed during revisualization, Dr. Buchsbaum explains that this is to be expected as a memory is essentially a condensed version of an original event.
The researchers are looking forward to exploring whether eye movements lead the brain to reactivate the memory or whether the brain stimulates the eye movements. Dr. Buchsbaum is also interested in whether visual tests that identify patients who are at risk for neurodegenerative diseases can be developed using this technique.
- M. Bone, et. al., Eye movement reinstatement and neural reactivation during mental imagery. Oxford Academic (2018). doi: 10.1093/cercor/bhy014.
- Image retrieved from: https://pixabay.com/en/african-american-man-eye-997244/