Neural activity during monkey vehicular wayfinding

Navigation gets us from place to place, creating a path to arrive at a goal. We trained a monkey to steer a motorized cart in a large room, beginning at its trial-by-trial start location and ending at a trial-by-trial cued goal location. While the monkey steered its autonomously chosen path to its goal, we recorded neural activity simultaneously in both the hippocampus (HPC) and medial superior temporal (MST) cortex. Local field potentials (LFPs) in these sites show similar patterns of activity with the 15–30 Hz band highlighting specific room locations. In contrast, 30–100 Hz LFPs support a unified map of the behaviorally relevant start and goal locations. The single neuron responses (SNRs) do not substantially contribute to room or start-goal maps. Rather, the SNRs form a continuum from neurons that are most active when the monkey is moving on a path toward the goal, versus other neurons that are most active when the monkey deviates from paths toward the goal. Granger analyses suggest that HPC firing precedes MST firing during cueing at the trial start location, mainly mediated by off-path neurons. In contrast, MST precedes HPC firing during steering, mainly mediated by on-path neurons. Interactions between MST and HPC are mediated by the parallel activation of on-path and off-path neurons, selectively activated across stages of this wayfinding task. •A monkey steered a motorized cart on a self-generated path to a cued room location while we recorded hippocampal (HPC) and medial superior temporal (MST) activity.•Local field potentials in HPC and MST highlight room locations.•Single neuron responses form a continuum from high activity when the monkey moved on a path to the goal, to high activity when the monkey deviates from paths to the goal.•Granger causality analysis suggests that on- and off-path neurons play separate roles in linking HPC and MST across distinct stages of the wayfinding task.