Context-Dependent Sensory Processing across Primary and Secondary Somatosensory Cortex

To interpret the environment, our brain must evaluate external stimuli against internal representations from past experiences. How primary (S1) and secondary (S2) somatosensory cortices process stimuli depending on recent experiences is unclear. Using simultaneous multi-area population imaging of projection neurons and focal optogenetic inactivation, we studied mice performing a whisker-based working memory task. We find that activity reflecting a current stimulus, the recollection of a previous stimulus (cued recall), and the stimulus category are distributed across S1 and S2. Despite this overlapping representation, S2 is important for processing cued recall responses and transmitting these responses to S1. S2 network properties differ from S1, wherein S2 persistently encodes cued recall and the stimulus category under passive conditions. Although both areas encode the stimulus category, only information in S1 is important for task performance through pathways that do not necessarily include S2. These findings reveal both distributed and segregated roles for S1 and S2 in context-dependent sensory processing. [Display omitted] •Mouse S1 and S2 encode overlapping information during a tactile working memory task•Recall responses of previous stimuli are more prevalent in S2 and are relayed to S1•Category information in S1, but not S2, is necessary for task performance•Network properties of S2 allow task information to persist across behavior states Condylis, Lowet, et al. investigate the roles of the primary and secondary somatosensory cortex during a tactile working memory task in mice. The authors find that during context-dependent sensory processing, handling of specific types of task-related information can occur in either a segregated or distributed manner across both areas.