Investigating agenesis of the corpus callosum using functional MRI: a study examining interhemispheric coordination of motor control.

We report fMRI findings in 3 asymptomatic cases of agenesis of the corpus callosum, the largest white matter bundle in the brain, which is responsible for interhemispheric transfer of information. Sensory information was presented to 1 hemisphere, and the patients had to generate a motor response governed by the contralateral hemisphere. Enhanced ipsilateral motor pathways have been suggested as a compensation method for people with agenesis of the corpus callosums; our functional magnetic resonance imaging data did not support this theory.