Corpus callosum damage and interhemispheric transfer of information following closed head injury in children

We evaluated the relationship of corpus callosum atrophy and/or lesions on magnetic resonance imaging (MRI) to functional hemispheric disconnection fo llowing closed head injury (CHI) in 51 pediatric patients, including mild C HI, moderate to severe CHI with extracallosal lesions, and moderate to seve re CHI with callosal atrophy and/or lesions. Interhemispheric transfer of i nformation was assessed using auditory, motor, tactile, and visual tests in patients and in 16 uninjured children. Total and regional callosal areas w ere measured from the midsagittal MRI slice by morphometry. The corpus call osum lesion group demonstrated a greater right ear advantage on verbal dich otic Listening than all other groups. Areas of the posterior corpus callosu m were negatively correlated with laterality indices of verbal dichotic lis tening performance and tachistoscopic identification of verbal material. Th e relationship of corpus callosum atrophy and/or lesions to asymmetry in di chotic listening is consistent with previous investigation of posttraumatic hemispheric disconnection effects in adults.