Language, communication, and the use of symbols in normal and autistic children.

The characteristics of language and other forms of communication in normal and autistic children are described. The main basis of comparison is the extent to which each group can comprehend and use spoken and nonspoken language and also develop inner language. It is suggested that the central problem in early childhood autism is an impairment of complex symbolic function affecting all forms of communication. This problem can occur on its own, but, in the majority of cases, it is associated with other impairments of the central nervous system. The relationship of early childhood autism to mental retardation and to normal intellectual function is discussed.