Structural changes of the visual analyzer of monkeys after extirpation of the occipital lobes

After uni- or bilateral extirpation of the occipital lobes from Papia hamadryas of different ages a study was made of the structure of the visual analyzer after the brains had been stained by Nissl and Shpielmayer's method. No regeneration of the extirpated portion occurred even in young monkeys which had undergone the operation at the ago of 4 or 5 days. With bilateral extirpation there was a degeneration of both external geniculate bodies, of the pulvinar of the thalamus, optic tracts, and of the caudal portions of the corpus calosum; when the extirpation was unilateral the degeneration of the structures we have mentioned occurred ipsilaterally. Degenerative changes of subcortical structures were less pronounced in the young monkeys.