Geometric and functional organization of cortical circuits

Shepherd, G. M. G., Stepanyants, A., Bureau, I., Chklovskii, D., Svoboda, K. (June 2005) Geometric and functional organization of cortical circuits. Nature Neuroscience, 8 (6). pp. 782-790. ISSN 1097-6256

Abstract

Can neuronal morphology predict functional synaptic circuits? In the rat barrel cortex, 'barrels' and 'septa' delineate an orderly matrix of cortical columns. Using quantitative laser scanning photostimulation we measured the strength of excitatory projections from layer 4 (L4) and L5A to L2/3 pyramidal cells in barrel- and septum-related columns. From morphological reconstructions of excitatory neurons we computed the geometric circuit predicted by axodendritic overlap. Within most individual projections, functional inputs were predicted by geometry and a single scale factor, the synaptic strength per potential synapse. This factor, however, varied between projections and, in one case, even within a projection, up to 20-fold. Relationships between geometric overlap and synaptic strength thus depend on the laminar and columnar locations of both the pre- and postsynaptic neurons, even for neurons of the same type. A large plasticity potential appears to be incorporated into these circuits, allowing for functional 'tuning' with fixed axonal and dendritic arbor geometry.

Item Type: Paper
Uncontrolled Keywords: Rat barrel cortex septa Primary visual cortex pyramidal neurons somatosensory cortex quantitative analysis axonal projections cerebral cortex spiny neurons Layer 4 Plasticity
Subjects: bioinformatics > quantitative biology
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors
organs, tissues, organelles, cell types and functions > cell types and functions > cell types > dendritic cells > dendritic arbors
organs, tissues, organelles, cell types and functions > sub-cellular tissues: types and functions > synapse
CSHL Authors:
Communities: CSHL labs > Chklovskii lab
Depositing User: CSHL Librarian
Date: June 2005
Date Deposited: 05 Jan 2012 17:53
Last Modified: 05 Jan 2012 17:53
URI: https://repository.cshl.edu/id/eprint/22701

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