Reorganization of adult rat barrel cortex intrinsic signals following kainic acid induced central lesion

A plasticity model studying the adult rat barrel cortex intrinsic signal af ter a central lesion was developed. Repeated optical imaging studies of the barrel cortex of five rats were performed over variable periods of time (2 days to 6 weeks) after intracortical injection of kainic acid. The signal of the elicited principal whisker corresponding to the injected barrel in t he repeat studies relocated to the perimeter of the lesion. The area of the signals of this principal whisker and of surrounding whiskers were larger in the first two weeks studies than those obtained before injection (P < 0. 01) resulting in increase overlapping of adjacent signals (P = 0.01). Even though the signal of the PW remains relocated in the later studies (>2 week s), all the signals returned to normal size. These findings demonstrate rec overy and reorganization of sensory representation in the somatosensory cor tex following a central lesion. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.