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Calvin, O. L.

Publications and source records attributed to Calvin, O. L..

2 recordsLinked to original sources

Hippocampal representations differentiate reactive and anticipatory responses during foraging under threat

Adaptive behavior under threat requires balancing reward pursuit against the risk of harm. During approach-avoidance conflict, animals often pause at decision points, but whether these pauses reflect a unified process or distinct decision states remains unclear. Here, we replicate and extend findings from Calvin et al. (2025) by analyzing hippocampal activity in rats performing a pseudo-predator foraging task across two cohorts. We compared mid-track aborts (MTAs), mid-track continues (MTCs), and retreats. Behaviorally, MTAs and MTCs emerged from a shared pause state but diverged in outcome, whereas retreats reflected rapid escape following attack. Despite similar endpoints, retreats and MTAs differed in movement dynamics and neural activity. During retreats, hippocampal representations remained biased toward the attack location. In contrast, representations during MTAs shifted toward safe locations. During pauses, representations differed according to subsequent behavior: pauses preceding MTAs showed greater decoded probability near the attack region, whereas pauses preceding MTCs showed greater decoded probability to goal locations. These differences were present during the outbound approach, suggesting decision-related processes emerged early on in the journey. Together, these findings dissociate hippocampal representations associated with reactive escape from those underlying anticipatory, anxiety-like decision-making, suggesting that the hippocampus dynamically tracks behaviorally relevant features to guide decisions under threat.

neuroscience↗

Dorsal hippocampus represents locations to avoid as well as locations to approach during approach-avoidance conflict

Worrying about perceived threats is a hallmark of multiple psychological disorders including anxiety. This concern about future events is particularly important when an individual is faced with an approach-avoidance conflict. Potential goals to approach are known to be represented in the dorsal hippocampus during theta sweeps. Similarly, important non-local information is represented during hippocampal high synchrony events (HSEs), which are correlated with sharp-wave ripples (SWRs). It is likely that potential future threats may be similarly represented. We examined how threats and rewards were represented within the hippocampus during approach-avoidance conflicts in rats faced with a predator-like robot guarding a food reward. We found representations of the pseudo-predator during HSEs when hesitating in the nest, and during theta prior to retreating as the rats approached the pseudo-predator. After the first attack, we observed new place fields appearing at the location of the robot (not the location the rat was when attacked). The anxiolytic diazepam reduced anxiety-like behavior and altered hippocampal local field potentials, including reducing SWRs, suggesting that one potential mechanism of diazepams actions may be through altered representations of imagined threat. These results suggest that hippocampal representation of potential threats could be an important mechanism that underlies worry and a potential target for anxiolytics.

neuroscience↗