Deficient brainstem encoding of pitch in children with Autism Spectrum Disorders

Objective: Deficient prosody is a hallmark of the pragmatic (socially contextualized) language impairment in Autism Spectrum Disorders (ASD). Prosody communicates emotion and intention and is conveyed through acoustic cues such as pitch contour. Thus, the objective of this study was to examine the subcortical representations of prosodic speech in children with ASD. Methods: Using passively evoked brainstem responses to speech syllables with descending and ascending pitch contours, we examined sensory encoding of pitch in children with ASD who had normal intelligence and hearing and were age-matched with typically developing (TD) control children. Results: We found that some children on the autism spectrum show deficient pitch tracking (evidenced by increased Frequency and Slope Errors and reduced phase locking) compared with TD children. Conclusions: This is the first demonstration of subcortical involvement in prosody encoding deficits in this population of children. Significance: Our findings may have implications for diagnostic and remediation strategies in a subset of children with ASD and open up an avenue for future investigations.