Time sharing and dichotic listening asymmetry in normal and learning-disabled children

Time-sharing and dichotic listening techniques were used to examine cerebral lateralization for language function in 48 normal and 48 learning-disabled children. All subjects were matched according to age, sex, and handedness. An analysis of results indicated that both nornal and learning-disabled children demonstrated left hemisphere lateralization of language function on the time-sharing and dichotic listening tasks. However, no developmental trends were evident for either group. Differences observed in the performance of the normal and learning-disabled children may relate to how each group utilizes “verbal strategies” and processes simultaneous information in the left hemisphere. The results strongly question the notion that attributes learning disabilities to incomplete or delayed language lateralization and lend support to the notion that cerebral lateralization is not a developmental phenomena.