The fates of the callosal neurons in neocortex after bisection of the corpus callosum, using the technique of retrograde neuronal labeling with two fluorescent dyes

The fate of callosal neurons after callosotomy is yet unclear although this has become a common surgical procedure for intractable generalized epilepsies. Using retrograde neuronal labeling with two fluorescent dyes, we demonstrated that callosal neurons in the parietal cortex of the adult rat survive up to 20 weeks after callosotomy. Our data suggest that these neurons possess numerous ipsilateral axon collaterals with indispensable functions in the ipsilateral hemisphere. (C) 1997 Elsevier Science B.V.