Prosodic Entrainment in Conversations of Verbal Children and Teens on the Autism Spectrum

Abstract

Unusual speech prosody has long been recognized as a characteristic feature of the speech of individuals diagnosed with Autism Spectrum Disorders (ASD). However, research to determine the exact nature of this difference in speech prosody is still ongoing. Many individuals with verbal autism perform well on tasks testing speech prosody. Nonetheless, their expressive prosody is judged to be unusual by others. We propose that one aspect of this perceived difference in speech prosody in individuals with ASD may be due to a deficit in the ability to entrain—or become more similar—to their conversation partners in prosodic features over the course of a conversation. In order to investigate this hypothesis, 24 children and teens between the ages of 9 and 15 years participated in our study. Twelve of the participants had previously been diagnosed with ASD and the other 12 participants were matched to the ASD participants in age, gender, and non-verbal IQ scores. All participants completed a goal-directed conversation task, which was subsequently analyzed acoustically. Our results suggest (1) that youth diagnosed with ASD entrain less to their conversation partners compared to their neurotypical peers—in fact, children and teens diagnosed with ASD tend to dis-entrain from their conversation partners while their neurotypical peers tend to converge to their conversation partners’ prosodic features. (2) Although age interacts differently with prosodic entrainment in youth with and without ASD, this difference is attributable to the entrainment behavior of the conversation partners rather than to those with ASD. (3) Better language skill is negatively correlated with prosodic entrainment for both youth with and without ASD. The observed differences in prosodic entrainment in children and teens with ASD may not only contribute to the perceived unusual prosody in youth with ASD but are also likely to be indicative of their difficulties in social communication, which constitutes a core challenge for individuals with ASD.