Development of Unconventional Verbal Behavior in Children With Pervasive Developmental Disorders: Focus on Functions of Unconventional Verbal Behavior

Children with pervasive developmental disorders frequently use stereotyped and repetitive language known as echolalia. In previous studies, these utterances have been defined as unconventional verbal behavior that could be classified into 4 types: immediate echolalia, delayed echolalia, incessant questioning, and repetitive language. It has been suggested that these 4 types of utterances differing functions, such as self-regulation, turn-taking, and protesting. In the present study, we examined the development of unconventional verbal behavior by focusing on these functions. When we interviewed the participants, who were the parents of 16 children with pervasive developmental disorders, we asked them: (1) the time when each function occurred, and (2) whether each function had disappeared or not. The results showed that in the children's developmental process, the self-stimulatory function of delayed echolalia had occurred before incessant questioning appeared. Moreover, some functions tended either to disappear or to continue during development. Finally, the developmental features of unconventional verbal behavior based on the various functions are discussed.