Data for: Distinct inhibitory neurons differently shape neuronal codes for sound intensity in the auditory cortex

Cortical circuits contain multiple types of inhibitory neurons which shape
how information is processed within neuronal networks. Here, we asked
whether somatostatin-expressing (SST) and vasoactive intestinal
peptide-expressing (VIP) inhibitory neurons may have distinct effects on
population neuronal responses for noise bursts of varying intensities. We
stimulated optogenetically SST or VIP neurons while simultaneously
measuring the calcium responses of populations of hundreds of neurons to
sounds. Upon SST neuronal activation, noise burst representations became
more discrete for different intensity levels, relying on cell identity
rather than strength. In contrast, upon VIP neuronal activation, noise
bursts of different intensity levels activated overlapping neuronal
populations, albeit at different response strengths. At the single-cell
level, SST and VIP neuronal activation differentially modulated the
response-level curves of monotonic and nonmonotonic neurons. SST neuronal
activation was consistent with a shift of the neuronal population
responses toward a more localist code with different cells responding to
sounds of different intensities. By contrast, VIP neuronal activation
shifted responses towards a more distributed code, in which sounds of
different intensity levels are encoded in the relative response of similar
cells. These results delineate how distinct inhibitory neurons in the
auditory cortex may dynamically control cortical population codes.
Different inhibitory neuronal populations may be recruited under different
behavioral demands, depending on whether categorical or invariant
representations are advantageous for the task.