Thu, 21 Aug 2008 15:30:10 BST CiteULike: klouie McCormick http://www.citeulike.org/user/klouie/author/McCormick CiteULike.org en-gb Copyright © 2004-2008 citeulike.org http://www.citeulike.org/user/klouie/article/969252 <i>Nature, Vol. 423, No. 6937. (15 May 2003), pp. 288-293.</i><br /><br />The vast majority of synaptic connections onto neurons in the cerebral cortex arise from other cortical neurons, both excitatory and inhibitory, forming local and distant 'recurrent' networks. Although this is a basic theme of cortical organization, its study has been limited largely to theoretical investigations, which predict that local recurrent networks show a proportionality or balance between recurrent excitation and inhibition, allowing the generation of stable periods of activity. This recurrent activity might underlie such diverse operations as short-term memory, the modulation of neuronal excitability with attention, and the generation of spontaneous activity during sleep. Here we show that local cortical circuits do indeed operate through a proportional balance of excitation and inhibition generated through local recurrent connections, and that the operation of such circuits can generate self-sustaining activity that can be turned on and off by synaptic inputs. These results confirm the long-hypothesized role of recurrent activity as a basic operation of the cerebral cortex. Turning on and off recurrent balanced cortical activity. Y Shu A Hasenstaub DA McCormick doi:10.1038/nature01616 Nature, Vol. 423, No. 6937. (15 May 2003), pp. 288-293. 2006-11-30T21:35:21-00:00 2003 Nature 0028-0836 423 6937 288 293 cat cortex inhibition neurophysiology rat