Abstract
The stability of neural dynamics arises through a tight coupling of excitatory (E) and inhibitory (I) signals. Genetically encoded voltage indicators (GEVIs) can report both spikes and subthreshold dynamics in vivo, but voltage alone only reveals the combined effects of E and I synaptic inputs, not their separate contributions individually. Here we combine optical recording of membrane voltage with simultaneous optogenetic manipulation to probe E and I individually in barrel cortex Layer 1 (L1) neurons in awake mice. Our studies show that L1 neurons integrate thalamocortical excitation and lateral inhibition to produce precisely timed responses to whisker stimuli. Top-down neuromodulatory inputs drive additional excitation in L1. Together, these results suggest a model for computation in L1 consistent with its hypothesized role in attentional gating of the underlying cortex.
One Sentence Summary All-optical electrophysiology revealed the function in awake mice of an inhibitory microcircuit in barrel cortex Layer 1.