Revisitation during visual exploration linked to memory durability and hippocampal dynamics

Humans use eye movements to sample the visual world, and these impact which information is retained in memory. However, memory is not only affected by the amount of time spent viewing a visual scene but also by specific gaze patterns during visual exploration. Revisitations occur when the eye gaze returns to a previously fixated location, resembling retrieval processes and offering another chance to encode. What remains unclear is whether revisitations actually enhance long-term memory formation and how they are associated with hippocampal activity dynamics. In this study, 50 human participants studied face and scene images. To analyze revisitations and hippocampal activity, we tracked participants’ eye gaze and used functional magnetic resonance imaging (fMRI) during the study period. Memory was tested immediately after study, as well as one week later to delineate longer-term, durable memories. Initial results revealed that the number of revisitations positively scaled with individual recognition memory performance (as indexed through d-prime) in both the immediate (N46, rPearson = 0.338, 95% CI = [0.053,0.572], ptwo-tailed = 0.022) and the delayed test (N46, rPearson = 0.314, 95% CI = [0.027, 0.554], ptwo-tailed = 0.033). Analyses of hippocampal activity dynamics and their link to revisitations are currently under way and first results will be presented at the meeting.