Hippocampus-ventral tegmental area structural connectivity patterns are associated with functional activation patterns of motivation

Poster Session C - Sunday, March 30, 2025, 5:00 – 7:00 pm EDT, Back Bay Ballroom/Republic Ballroom

Blake Elliott¹ (blake.elliott@temple.edu), Vishnu Murty²; ¹Temple University, ²University of Oregon

While a large body of work has highlighted the role of the hippocampus in spatial navigation/episodic memory, the hippocampus is also critical for motivated behaviors putatively driven by its connectivity with the dopaminergic midbrain (e.g., VTA). While functional activation patterns of motivation and navigation have been well-studied, less is known about the structural connectivity underlying these patterns. In this study, we investigated the relationship between hippocampus–ventral tegmental area (VTA) structural connectivity and functional activation patterns associated with the hippocampus (motivation and navigation). Using a large sample of subjects (N = 628) from the Human Connectome Project dMRI data release, we previously found that connectivity profiles with the hippocampus and VTA showed stronger connectivity with the anterior versus posterior hippocampus. When comparing the voxel-level pattern of connectivity with meta-analytic functional activation maps of the term “motivation,” we identified a strong positive correlation between left (𝜌 = 0.61, p < 0.01) and right (𝜌 = 0.20, p < 0.01) hippocampus–VTA structural connectivity and motivation-related activation patterns. Notably, anterior hippocampus-VTA connectivity and anterior hippocampus functional activation patterns were most pronounced, consistent with hypothesized functional gradients of hippocampal involvement in reward and motivation. However, we found no relationship between hippocampus-VTA structural connectivity and functional activation maps of the term “navigation” for both the left (𝜌 = 0.002, N.S.) and right (𝜌 = 0.06, N.S.) hippocampus. These findings provide novel evidence selectively linking hippocampus–VTA structural connectivity with task-evoked functional patterns, offering new insights into how hippocampal circuits support goal-directed behavior.

Topic Area: LONG-TERM MEMORY: Episodic