A Layered Microcircuit Model of Somatosensory Cortex with Three Interneuron Types and Cell-Type-Specific Short-Term Plasticity

Abstract

Three major types of GABAergic interneurons, the parvalbumin- (PV), somatostatin- (SOM) and vasoactive intestinal peptide-expressing (VIP) cells, play critical but distinct roles in the cortical microcircuitry. Their inhibitory functions are shaped by their specific electrophysiology and connectivity. To study how this diversity contributes to the dynamics and signal processing in the cerebral cortex, we developed a multi-layer model incorporating biologically realistic parameters of these interneurons from rodent somatosensory cortex. With in vivo data as criteria, the model shows plausible resting-state activity and responses to sensory stimulation. With a protocol of cell-type-specific stimulation, network responses when activating different neuron types are examined. The model reproduces the experimentally observed inhibitory effects of PV and SOM cells and disinhibitory effect of VIP cells on excitatory cells. In addition, responses of VIP cells to cell-type-specific stimulation provide predictions for future experiments. We further create a version of the model incorporating cell-type-specific short-term synaptic plasticity (STP). While the ongoing activity with and without STP is similar, STP modulates the responses of SOM and VIP cells to cell-type-specific stimulation, presumably by changing the dominant inhibitory pathways. Our model can serve to explore the computational roles of inhibitory interneurons and short-term synaptic plasticity in sensory functions.

Cell type specific firing patterns in a V1 cortical column model depend on feedforward and feedback-driven states

“…The mixed effects observed upon stimulating (SST, VIP and PV) interneurons suggests the importance of considering the diverse roles of different neuronal populations within the column 8,45,1,46,5 ,. For istance, our the perturbation analysis of feedback states (Fig.…”

“…The intricate architecture of the cerebral cortex, with its diverse neuronal populations and complex connectivity patterns, plays a pivotal role in processing sensory information and orchestrating cognitive functions 1,2 . Central to this architecture is the column-like circuitry, a functional unit that has been the subject of extensive research over the years 3,4,5 . Within these columns, different neuronal populations interact in a dynamic manner 6 , giving rise to a rich repertoire of activity patterns that can be modulated by both internal and external factors 7 .…”