Aphasia and agraphia in lesions of the posterior internal capsule and putamen.

We studied three right-handed patients with small, lacunar infarcts localized by CT to the posterior and lateral putamen and the posterior limb of the internal capsule. All had moderate or severe right hemiparesis and mild aphasia that was not characteristic of any traditional aphasia syndrome. Two had mild dysarthria. Aphasic abnormalities included mild, nonfluent, telegraphic speech and mild, fluent aphasia with impaired repetition, naming, and comprehension. All three had severely impaired writing. Unlike previously reported patients with subcortical infarcts, these cases indicate that small lesions limited to the posterior capsuloputaminal area can cause aphasia and agraphia as well as dysarthria.