Effects of Threat on Decision-Making and Activity Profiles of Neuronal Subpopulations in the Tail of the Striatum

Animals must balance exploitation of available resources with exploration of alternatives while accounting for travel costs and environmental threats. The tail of the striatum (TS) may integrate salient sensory information with action selection, but how its principal subpopulations contribute to this trade-off remains unclear. D1- and Adora2a-expressing TS neuronal subpopulations have been implicated in distinct responses to threatening stimuli and are hypothesized to differentially bias exploitation and threat-driven exploration. Here, we use a linear virtual reality foraging task to study exploration/exploitation decisions in head-fixed, water-restricted mice. The task comprises rewarded zones separated by non-rewarded corridors. We analyze the activity of these subpopulations using fiber photometry during task performance and present preliminary behavioral and fiber photometry results from two independent comparisons: short versus long corridors, and short corridors with or without threatening bird-call stimuli. Behaviorally, animals adopted more exploitative strategies when corridors were long rather than short; within short corridors, exposure to threatening bird calls shifted behavior toward exploration relative to threat-free corridors. Fiber photometry results indicate that D1- and Adora2a-expressing TS neuronal subpopulations exhibit distinct activity profiles across different phases of the task.