Supralinear increase of recurrent inhibition during sparse activity in the somatosensory cortex.

Published

Journal Article

The balance between excitation and inhibition in the cortex is crucial in determining sensory processing. Because the amount of excitation varies, maintaining this balance is a dynamic process; yet the underlying mechanisms are poorly understood. We show here that the activity of even a single layer 2/3 pyramidal cell in the somatosensory cortex of the rat generates widespread inhibition that increases disproportionately with the number of active pyramidal neurons. This supralinear increase of inhibition results from the incremental recruitment of somatostatin-expressing inhibitory interneurons located in layers 2/3 and 5. The recruitment of these interneurons increases tenfold when they are excited by two pyramidal cells. A simple model demonstrates that the distribution of excitatory input amplitudes onto inhibitory neurons influences the sensitivity and dynamic range of the recurrent circuit. These data show that through a highly sensitive recurrent inhibitory circuit, cortical excitability can be modulated by one pyramidal cell.

Full Text

Duke Authors

Cited Authors

  • Kapfer, C; Glickfeld, LL; Atallah, BV; Scanziani, M

Published Date

  • June 2007

Published In

Volume / Issue

  • 10 / 6

Start / End Page

  • 743 - 753

PubMed ID

  • 17515899

Pubmed Central ID

  • 17515899

International Standard Serial Number (ISSN)

  • 1097-6256

Digital Object Identifier (DOI)

  • 10.1038/nn1909

Language

  • eng

Conference Location

  • United States