Lateral asymmetries in finger-tapping by adolescents and young adults with Down syndrome.

Lateral asymmetries in finger-tapping were compared in right-handed adolescents and young adults with and without Down syndrome in order to examine cerebral specialization in the Down syndrome group. Finger-tapping data revealed that subjects with Down syndrome performed more slowly than did control subjects and failed to show a right-hand tapping advantage. Although the latter finding suggests that individuals with Down syndrome are less lateralized for sequential processing, they exhibited the same pattern of tapping variability as did control subjects; i.e., they were more variable when finger-tapping with their left hands.