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An embedded subnetwork of highly active neurons in the neocortex.

ABSTRACT: Unbiased methods to assess the firing activity of individual neurons in the neocortex have revealed that a large proportion of cells fire at extremely low rates (<0.1 Hz), both in their spontaneous and evoked activity. Thus, firing in neocortical networks appears to be dominated by a small population of highly active neurons. Here, we use a fosGFP transgenic mouse to examine the properties of cells with a recent history of elevated activity. FosGFP-expressing layer 2/3 pyramidal cells fired at higher rates compared to fosGFP(-) neurons, both in vivo and in vitro. Elevated activity could be attributed to increased excitatory and decreased inhibitory drive to fosGFP(+) neurons. Paired-cell recordings indicated that fosGFP(+) neurons had a greater likelihood of being connected to each other. These findings indicate that highly active, interconnected neuronal ensembles are present in the neocortex and suggest these cells may play a role in the encoding of sensory information.

SUBMITTER: Yassin L

PROVIDER: S-EPMC3022325 | biostudies-literature | 2010 Dec

REPOSITORIES: biostudies-literature

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An embedded subnetwork of highly active neurons in the neocortex.

Yassin Lina L Benedetti Brett L BL Jouhanneau Jean-Sébastien JS Wen Jing A JA Poulet James F A JF Barth Alison L AL

Neuron 20101201 6

<h4>Video abstract</h4>Unbiased methods to assess the firing activity of individual neurons in the neocortex have revealed that a large proportion of cells fire at extremely low rates (<0.1 Hz), both in their spontaneous and evoked activity. Thus, firing in neocortical networks appears to be dominated by a small population of highly active neurons. Here, we use a fosGFP transgenic mouse to examine the properties of cells with a recent history of elevated activity. FosGFP-expressing layer 2/3 pyr ...[more]

PMID: 21172607

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