Normal repetitive and abnormal stereotyped behavior of nonretarded infants and young mentally retarded children.

The topographical similarities and differences between repetitive behaviors exhibited by 12 nonretarded infants and 11 severely mentally retarded children were examined. An analysis of stereotyped body-rocking and hand-gazing behavior exhibited by both groups demonstrated topographical differences. The results and methodology of this study may be of value to future investigators examining the ontogenesis of stereotyped behavior and may assist in the early identification and amelioration of these pathological behaviors.