Contextual gating of whisker-evoked responses by frontal cortex supports flexible decision making

Context-dependent sensory processing underlies important aspects of flexible behavior. Here, we investigate how mice can use a briefly-presented auditory contextual Go or Nogo cue after a delay period to gate the transformation of a whisker deflection into licking for reward. Spatiotemporally-specific optogenetic inactivation demonstrated an important contribution of various cortical regions during distinct trial epochs, with only whisker secondary motor cortex (wM2) contributing strongly to all task epochs including auditory cue, delay and whisker stimulus. Electrophysiological recordings revealed prominent context representation in both wM2 and anterolateral motor cortex (ALM) in the form of persistent activity with stable population dynamics. Notably, we found that context and whisker sensory processing appeared to be integrated first in wM2, whose activity predicted future lick initiation in both correct hit trials and false alarm error trials already within 30 ms after whisker deflection. We thus identify wM2 as a key node for the contextual gating of the transformation of whisker sensation into motor commands for goal-directed licking.