Disconnection and cerebral metabolism. The case of conduction aphasia.

Ten patients with conduction aphasia were studied with computed tomography and 18-F-fluorodeoxyglucose positron emission tomography to examine glucose metabolism. Computed tomographic results identified a postrolandic structural locus for conduction aphasia. All patients demonstrated resting glucose hypometabolism throughout the parietal and temporal regions, and half of the patients also demonstrated reduced metabolic rates in the posterior, inferior, frontal (Broca's) regions. These data suggest that disconnection between posterior and anterior language areas may not be the best anatomical explanation for conduction aphasia.