Attempts to identify deficits in object knowledge specific to the autistic syndrome. Examines the correspondence between sensorimotor and play behaviors and language in mentally retarded and normal children. Determines whether these correspondences are different for autistic, mentally retarded, and normal children.(Author/AS)

Home movies of eight normal children and eight children later diagnosed as autistic were analyzed based on: (1) Piagetian criteria of sensorimotor development and semiotic functioning, and (2) developmental levels of action competencies. The age range covered was 4 to 42 months of age. The analysis showed that, from the second year of life, timing…