Verbal control of motor behaviour in mentally retarded children: a re-examination of Luria's theory.

A battery of tasks to indicate stage membership within the Lurian theory of development of verbal control of motor behaviour was given to children whose moderate level of mental retardation derived from organic pathology, familiar conditions or Down syndrome, and to a group of normal preschool children matched for mental age. The results supported Luria's contention that the development of mentally retarded children, regardless of aetiology, is arrested at the second (asemantic) stage and that their performance deficiencies are even greater than might be predicted simply on the basis of their developmental level.