Bilateral representation of language function. Agenesis of corpus callosum by Wada and PET activation.

A 33-year-old right-handed man with intermittent headache was found to have agenesis of the corpus callosum. He underwent magnetic resonance imaging, positron emission tomography (PET), and detailed neuropsychologic tests, including a Wada test. There was bilateral representation of language, and a PET activation study with word repetition revealed bilateral areas of activation that were not completely symmetric. These findings and the literature concerning agenesis of the corpus callosum are discussed as is the possible compensatory mechanism for absence of the corpus callosum, which is important for cross-communication.