Evidence of altered dominance in children with congenital spastic hemiplegia.

Abstract

The study aimed at investigating lateralization effects and signs of transfer and crowding in children with congenital lateralized brain damage with the aid of a dichotic listening test, a chimeric test, and verbal and nonverbal neuropsychological tests. Thirty-three children with spastic hemiplegia and 86 control children (age 5.0-12.0 yr) were assessed. Children with left-hemisphere damage (n = 17) were found to have a pathological left-ear advantage for verbal material, and children with right-hemisphere damage (n = 16) were found to have a pathological right visual half-field advantage for visual material. Children with left-hemisphere damage and a left-ear advantage on the dichotic test were also found to have a right visual half-field advantage on the chimeric test, which was regarded as a sign of reversed dominance. No verbal or nonverbal differences emerged between the left-hemisphere and the right-hemisphere damage groups, nor did differences emerge when the children were reclassified by considering children with left hemisphere damage and signs of reversed dominance as having damage to the nondominant hemisphere. It was concluded that although lateralized brain damage may alter the dominance for verbal and visual functions, there is still considerable inter-individual variability with respect to inter- and intrahemispheric neural adjustment to damage. The dichotic and the chimeric tests did not indicate the presence of brain damage accurately, but they indicated the lateralization of damage in children with stated abnormality with a high degree (91.3%) of accuracy.