Schedule of Events | Symposia

Influence of aging on medial frontal and hippocampal contributions to interactions between new and old route memories

Poster Session A - Saturday, March 29, 2025, 3:00 – 5:00 pm EDT, Back Bay Ballroom/Republic Ballroom

Paulina Maxim¹, Scott D Moffat¹, Thackery I Brown¹; ¹Georgia Institute of Technology

Research suggests that aging negatively impacts flexible navigation performance, likely due to memory integration and route-memory deficits. Our study tested young (YA, 18-35) and older adults (OA, 65-80) across two days in a virtual navigation task and used fMRI to test complementary views of how the medial temporal lobe and medial prefrontal cortex contribute to route planning and navigation from prior knowledge. We demonstrate a complex relationship between navigation strategy (familiar vs. shortcut), route directionality (forward vs. backward), and execution (efficiency of strategy). We saw no significant differences in navigation strategy and efficiency between age groups when taking shortcuts directionally aligned with familiar-but-longer routes. However, in scenarios when shortcuts take a different direction from familiar routes (FR), OAs show a significant bias away from the FR preference of young adults in such circumstances. This context-dependent preference for wayfinding in OAs may be accounted for by indicators that nearly every OA found remembering the FR more difficult than YAs. Findings suggest that route familiarity and directional conflict may be important moderators of past evidence that aging otherwise decreases flexibility and increases route-based navigation. YA fMRI data reveal 1) representational similarity between current and past routes show divergent relationships to navigator performance in different subdivisions of mPFC, and 2) broad agreement between when and how the hippocampus and mPFC are engaged for task stages, represent environments, and track participant differences. OA analyses will help further unpack the impact aging has on how individuals execute navigational strategies and the neural factors at play.

Topic Area: EXECUTIVE PROCESSES: Development &aging