Columnar architecture sculpted by GABA circuits in developing cat visual cortex.
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ABSTRACT:
SUBMITTER: Hensch TK
PROVIDER: S-EPMC2562723 | biostudies-literature | 2004 Mar
REPOSITORIES: biostudies-literature
Publications
Columnar architecture sculpted by GABA circuits in developing cat visual cortex.
Hensch Takao K TK Stryker Michael P MP
Science (New York, N.Y.) 20040301 5664
The mammalian visual cortex is organized into columns. Here, we examine cortical influences upon developing visual afferents in the cat by altering intrinsic gamma-aminobutyric acid (GABA)-mediated inhibition with benzodiazepines. Local enhancement by agonist (diazepam) infusion did not perturb visual responsiveness, but did widen column spacing. An inverse agonist (DMCM) produced the opposite effect. Thus, intracortical inhibitory circuits shape the geometry of incoming thalamic arbors, suggest ...[more]
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