THALAMIC-STRIATAL INTERACTIONS DURING TACTILE DECISION MAKING IN FREELY MOVING MICE

Tactile information acquired through the whiskers is a primary sensory modality guiding decision making in rodents. While early somatosensory pathways have been extensively characterized, it remains unclear how higher-order thalamic signals interact with motivational circuits to transform tactile input into value-based actions. The posterior medial nucleus of the thalamus (POm) is a higher-order somatosensory nucleus implicated in context-dependent modulation of whisker signals, learning, and behavioral state. In parallel, the nucleus accumbens (NAc) integrates sensory, motivational, and motor-related information to guide action selection and response vigor. However, how POm-related activity relates to neuronal representations in the NAc during tactile decision making is largely unknown.
Here, we present an ongoing project designed to investigate thalamostriatal interactions during a whisker-based go/no-go discrimination task in freely moving mice. Using Neuropixels recordings, we simultaneously record neuronal population activity in POm and NAc while animals perform a tactile aperture discrimination task with rule reversals and contingency degradation. Behavioral variables, including whisker touch timing, licking, locomotion, and outcomes, are tracked with high temporal precision. Neural data are analyzed to dissociate sensory, motor, outcome-related, and putative state-dependent contributions to single-neuron firing.
This project aims to establish the technical feasibility and analytical framework required to test whether POm-related population signals are systematically related to striatal representations of tactile information and value. The results will provide a foundation for future causal experiments and a mechanistic investigation of thalamic contributions to flexible, value-guided behavior.