Visual Neuroscience

Research Articles

Development of inhibitory mechanisms in the kitten's visual cortex

Eric S. Greena1, Gregory C. DeAngelisa2 and Ralph D. Freemana1

a1 Group in Neurobiology, School of Optometry, University of California, Berkeley

a2 Department of Neurobiology, Stanford University, Palo Alto

Abstract

The objective of this study was to evaluate the maturity of three inhibitory mechanisms (end-inhibition, side-inhibition, and cross-orientation inhibition) in the striate cortex of kittens at 4 weeks postnatal. To accomplish this, we made extracellular recordings from area 17 neurons while presenting visual stimuli consisting of sinusoidal luminance gratings or composites of gratings. We then compared data from kittens relating to various characteristics of each inhibitory mechanism with data from adults. We find that end-inhibition, side-inhibition, and cross-orientation inhibition are all present in kittens, and all show signs of maturity by 4 weeks postnatal. We conclude that the development of these inhibitory mechanisms occurs relatively early, and may coincide with the development of excitatory properties.

(Received March 06 1996)

(Accepted May 22 1996)

Footnotes

Reprint requests to: Ralph D. Freeman, 360 Minor Hall, University of California at Berkeley, Berkeley, CA 94720-2020, USA.