Pyramidal cell subtype-dependent cortical oscillatory activity regulates motor learning

Takeshi Otsuka,Yasuo Kawaguchi

doi:10.1038/s42003-021-02010-7

Abstract

The cortex processes information through intricate circuitry and outputs to multiple brain areas by different sets of pyramidal cells (PCs). PCs form intra- and inter-laminar subnetworks, depending on PC projection subtypes. However, it remains unknown how individual PC subtypes are involved in cortical network activity and, thereby, in distinct brain functions. Here, we examined the effects of optogenetic manipulations of specific PC subtypes on network activity in the motor cortex. In layer V, the beta/gamma frequency band of oscillation was evoked by photostimulation, depending on PC subtypes. Our experimental and simulation results suggest that oscillatory activity is generated in reciprocal connections between pyramidal tract (PT) and fast-spiking cells. A similar frequency band was also observed in local field potentials during a pattern learning task. Manipulation of PT cell activity affected beta/gamma band power and learning. Our results suggest that PT cell-dependent oscillations play important roles in motor learning.

Highlights

The cortex processes information through intricate circuitry and outputs to multiple brain areas by different sets of pyramidal cells (PCs)
To understand how L5 cell activity is regulated during cortical information processing, we examined response patterns of L5 cells evoked by L2/3 PC stimulation, a major feed-forward excitatory pathway in the motor cortex
We investigated how PC subtypes contribute to cortical network activity

Summary

Introduction

The cortex processes information through intricate circuitry and outputs to multiple brain areas by different sets of pyramidal cells (PCs). PCs form intra- and inter-laminar subnetworks, depending on PC projection subtypes It remains unknown how individual PC subtypes are involved in cortical network activity and, thereby, in distinct brain functions. Information is processed through inter- and intra-laminar connections in the cortex and routed to several subcortical and other cortical areas through different sets of pyramidal cells (PCs). Intraand inter-laminar synaptic connections between PCs depend on PC projection subtypes[4,6,8,9,10] These observations suggest that cortical PC networks are segregated into functional channels corresponding to different target areas. Recent studies have suggested the contribution of specific PC subtypes in learned behavior[11,12] It remains unknown how individual PC subtypes regulate cortical network activity and, thereby, brain function. Our results suggest that oscillatory activity is generated through reciprocal interactions between PT and FS cells and regulates motor learning

Methods

Results

Conclusion