Perception of human and nonhuman facial age by developmentally disabled children.

Human and nonhuman faces were shown to clinical controls, autistic, mentally retarded, and language-disordered children to assess their ability to detect and draw inferences about facial age. Children were asked to select from sets of three faces the one that appeared youthful or to select faces that would be associated with some age-related characteristic. In two studies, it was found that, relative to other children, autistic children had more difficulty perceiving youthfulness in nonhuman faces compared with human faces. These data are discussed with respect to differences in mechanisms and processes that may underlie facial information processing in autistic and nonautistic children.