Eye Movements Play a Role in Memory Retrieval, Baycrest Study Finds

A new study conducted by Baycrest researchers indicates that shifts in eye movements play a role in memory retrieval. The findings suggest a link between eye movements and how experiences are recalled, potentially offering insight into memory function and changes related to brain disease.

Key Findings

Research showed that eye movements, specifically saccades, increased immediately before individuals recalled episodic details of past events (e.g., what was seen, heard, or felt). Crucially, eye movements decreased immediately after these details were recalled. This distinct pattern was not observed during the recall of non-episodic details, such as general facts or background information.

Dr. Brian Levine, a Senior Scientist at Baycrest's Rotman Research Institute and senior author of the study, stated:

"These findings suggest a close connection between eye movements and the brain's processing and reconstruction of visual and spatial memories."

Study Methodology

The study involved 91 healthy young adults who participated in two ten-minute audio-guided tours of artworks and installations. One week later, participants recalled the tour while viewing a blank screen, with their eye movements recorded by a video-based eye-tracking system. This method allowed for the synchronization of eye movements with the timing of spoken narrative details.

Implications

The research highlighted several key implications:

• Eye movements increased approximately half a second before participants recalled episodic, event-specific details.
• Eye movements decreased in the period immediately following the recall of these specific details.
• The identified eye movement patterns suggest that visual exploration contributes to the reconstruction of real-life experiences.

Understanding the mechanisms of memory retrieval could support the development of more sensitive tools for assessing brain health, particularly in neurological conditions such as dementia.

Dr. Levine noted that natural behaviors like eye movements could complement traditional memory assessments in research and clinical settings. The researchers also suggested that similar principles might apply to conditions like Post-traumatic Stress Disorder (PTSD), where intrusive visual memories are a factor.

Future Research

Future longitudinal studies are necessary to determine how these eye-movement patterns evolve with normal aging and neurodegenerative disease, and whether they could serve as early indicators of memory decline.

The research was led by Ryan Barker, a PhD student at Baycrest and the University of Toronto, and Dr. Jennifer Ryan, a Senior Scientist at Baycrest's Rotman Research Institute.