Communicative Acts of Children with Autism Spectrum Disorders in the Second Year of Life

Impairments in social communication are among the earliest indicators of autism spectrum disorders (ASD). However, due to the age of usual diagnosis, relatively little is known about the communicative profiles of children with ASD younger than 2 years of age. The purpose of this study was to examine the communicative acts of 50 children between 18 and 24 months of age who were later diagnosed with ASD, compared to children with developmental delays (DD, n=23) in whom ASD was ruled out and children with typical development (TD, n=50). Precise measures of rate, functions, and means of communication were obtained through systematic observation of videotaped behavior samples from the Communication and Symbolic Behavior Scales Developmental Profile (Wetherby & Prizant, 2002). Children with ASD communicated at a significantly lower rate than children with DD and TD; however, differences in rate varied based on communicative function, with the ASD group communicating at a lower rate for behavior regulation and joint attention than children with TD, and a lower rate on joint attention compared to children with DD. Children with ASD who did communicate for joint attention were as likely as other children to coordinate means of communication, including vocalizations, eye gaze, and gestures. In addition, the ASD group used a significantly lower rate of total communicative gestures than the DD and TD groups, along with a lower rate and proportion of deictic gestures and a reliance on more primitive gestures. Profile analyses of communicative acts and gestures revealed that children with ASD exhibited a unique profile of communication across communicative functions and gestures. Overall, the results of this study indicated that by 18 to 24 months of age, children with ASD showed a unique profile of communication, with core deficits in communication rate, joint attention, and communicative gestures. This study will contribute to understanding the ontogeny of communication in children with ASD and aid in early detection.