CORTICAL INPUT-SPECIFIC RECRUITMENT OF COLLICULAR CIRCUITS IMPLICATED IN VISUAL DISTRACTION ENGAGEMENT

The superior colliculus (SC) is a multimodal processing hub in the midbrain, contributing to visuospatial attention and distraction control, among other functions. Cortical input from the visual and frontal areas converges into the lateral intermediate SC, regulated by its local network, to contribute to sensorimotor integration and salience processing in ways not yet fully understood. Our previous work suggests that distractor engagement may depend less on suppressive filtering and more on motor cortical state-dependent gating of visual information as it gains access to collicular circuits. Therefore, we investigate how these inputs interact within collicular microcircuits to influence local excitatory and inhibitory neurons. Using pathway-specific optogenetics together with ex vivo whole-cell recordings and in vivo high-density electrophysiology, we assess how distinct long-range projections recruit and modulate local networks in the lateral SC. Rather than acting as simple drivers, these inputs appear to differentially engage excitation and inhibition, pointing to input-specific modes of circuit recruitment. Preliminary observations indicate that sensory and motor-related activity may operate through distinct integration regimes that determine when visual responses are amplified, gated, or transmitted to downstream motor pathways. Ongoing experiments aim to clarify how these interactions contribute to visual distraction regulation during goal-dependent behavior.