Callosal apraxia without agraphia.

We describe a patient with left unilateral ideomotor apraxia without left-sided agraphia caused by a callosal lesion that was demonstrated by magnetic resonance imaging. The clinical features, together with data in the literature, suggest that the callosal fibers for writing are concentrated in the posterior corpus callosum, while those for praxis cross in the more rostral part of the posterior half of the callosum.