A Computational Analysis of the Function of Three Inhibitory Cell Types in Contextual Visual Processing

TL;DR

This paper uses computational modeling to explore how three distinct inhibitory neuron types in the mouse visual cortex contribute to different aspects of contextual visual processing, revealing their specific functional roles.

Contribution

It provides a novel computational framework linking inhibitory cell types' structure to their distinct functions in visual context processing.

Findings

PV cells mediate local boundary detection

SST cells facilitate long-range spatial competition

VIP interneurons enhance V1 responses through top-down modulation

Abstract

Most cortical inhibitory cell types exclusively express one of three genes, parvalbumin, somatostatin and 5HT3a. The visual responses of cortical neurons are affected not only by local cues, but also by visual context. As the inhibitory neuron types have distinctive synaptic sources and targets over different spatial extents and from different areas, we conjecture that they possess distinct roles in contextual processing. We use modeling to relate structural information to function in primary visual cortex (V1) of the mouse, and investigate their role in contextual visual processing. Our findings are threefold. First, the inhibition mediated by parvalbumin positive (PV) cells mediates local processing and could underlie their role in boundary detection. Second, the inhibition mediated by somatostatin-positive (SST) cells facilitates longer range spatial competition among receptive fields. Third, non-specific top-down modulation to interneurons expressing vasoactive intestinal polypeptide (VIP), a subclass of 5HT3a neurons, can selectively enhance V1 responses.