Abstract

Dr. Jen Ryan
Department of Psychology University of Toronto

The intersection between memory and active vision

The oculomotor and hippocampal memory systems interact in a reciprocal manner, on a moment-to-moment basis. Eye movements serve to accumulate information from the visual world, contributing to the formation or updating of coherent memory representations. Conversely, memory influences ongoing viewing behavior by increasing the efficiency of active vision. Eye movements can even contribute functionally to memory retrieval by reconstructing the rich, vivid, spatiotemporal details from memory (gaze reinstatement). However, the interactions between the oculomotor and memory systems are altered in aging. In older adults, neural activity in the hippocampus is not modulated by gaze fixations to the same extent as observed in younger adults, despite the fact that older adults typically enact more gaze fixations than younger adults. Older adults also exhibit less unique patterns across different stimuli, and across repeated viewings of the same stimulus. Together, these findings suggest that the memory representations formed by older adults may be less complete and/or less distinct than those of younger adults. Consequently, even when older adults engage in gaze reinstatement at retrieval, such reinstatement does not necessarily support accurate memory performance, and instead, may explain memory errors that are observed with aging. This work highlights how age-related changes in the hippocampal memory system may have a broad impact on active vision.