Neural dynamics in superior colliculus of freely moving mice

Vision is an active process that depends on head and eye movements to explore the visual environment. Superior colliculus (SC) is known for its role in both generating these movements and processing visual information, but has not been studied extensively during free movement. To determine the impact of active vision on neural dynamics in mouse SC, we recorded neural activity across the depth of SC during free movement while simultaneously recording eye and head position. We show that superficial SC neurons respond to visual input following gaze-shifting saccadic movements, with a coarse-to-fine progression related to that observed in primary visual cortex (V1). On the other hand, activity in deep SC neurons corresponds to the motor component of gaze shifts, primarily for head movements rather than eye movements. Our results highlight the diverse roles of SC during active vision, while also revealing distinct differences in visual processing between SC and V1.