Signs of interhemispheric disconnection in marchiafava-bignami disease.

We report three cases of Marchiafava-Bignami disease. The diagnosis was made on clinical grounds. Evidence of interhemispheric disconnection was found in all three cases. This included left hand anomia, left-sided apraxia, left-hand agraphia, and left-sided pseudoextinction to both visual and tactile stimuli. In two cases, there was a left-ear extinction on a dichotic listening test.