Effects of hemispheric side of injury, age at injury, and presence of seizure disorder on functional ear and hand asymmetries in hemiplegic children

Dichotic listening, manual functions, and IQ were measured in a large group of hemiplegic children with unilateral hemispheric damage. In the children without a history of seizure disorder, only manual functions were impaired, but in those with such a history (and hence a regime of anticonvulsant medication), all measures were affected. Some children with congenital left hemisphere lesions (with and without seizure disorder) showed a left ear advantage for dichotic digits as well as greater impairment in right hand function than those who showed the usual right ear advantage. The latter result suggests that the hemipheric damage in the subgroup with altered ear asymmetry was greater than in the others and extensive enough to encroach on language areas, shifting language representation to the right.