Context flexibly modulates cue representations in visual cortex.

Learned sensory cues result in enhanced responses in sensory cortices and, in turn, enhanced responses draw attention towards cues in our environment that guide future decision making. To respond appropriately, one must recognize the cue but also the context. Here we use two-photon imaging in visual cortex as mice learn a visual discrimination task and subsequently experience a change in external context through introduction of a threat stimulus. Stimuli associated with a reward elicit an enhanced response due to newly recruited neurons responding preferentially to the rewarded cue in addition to neurons increasing their response magnitude. Introduction of threat results in a largely separate set of neurons encoding cues, but the maintenance of the enhanced response to a rewarded cue. When the threat is relieved, representations revert to their initial state. These data suggest that external context changes can result in rapid but flexible shifts in the representation of visual cues.