Enhanced Pitch Sensitivity in Individuals with Autism: A Signal Detection Analysis

TLDR

Prior studies indicate that high‑functioning autistic individuals outperform controls in pitch memory and detection, and that some possess absolute pitch, suggesting an unusually fine‑grained pitch sensitivity. The study aimed to test whether high‑functioning autism is associated with enhanced pitch sensitivity. Using signal‑detection psychoacoustic tasks, 12 musically untrained high‑functioning autistic participants and 12 normally developing controls judged pure tones in same‑different and high‑low categorization tasks. Both tasks revealed that autistic participants had higher pitch sensitivity, especially in categorization, confirming enhanced auditory processing and extending prior visual‑domain findings of superior low‑level perception in autism.

Abstract

Abstract Past research has shown a superiority of participants with high-functioning autism over comparison groups in memorizing picture-pitch associations and in detecting pitch changes in melodies. A subset of individuals with autism, known as “musical savants,” is also known to possess absolute pitch. This superiority might be due to an abnormally high sensitivity to fine-grained pitch differences in sounds. To test this hypothesis, psychoacoustic tasks were devised so as to use a signal detection methodology. Participants were all musically untrained and were divided into a group of 12 high-functioning individuals with autism and a group of 12 normally developing individuals. Their task was to judge the pitch of pure tones in a “same-different” discrimination task and in a “high-low” categorization task. In both tasks, the obtained psychometric functions revealed higher pitch sensitivity for subjects with autism, with a more pronounced advantage over control participants in the categorization task. These findings confirm that pitch processing is enhanced in “high-functioning” autism. Superior performance in pitch discrimination and categorization extends previous findings of enhanced visual performance to the auditory domain. Thus, and as predicted by the enhanced perceptual functioning model for peaks of ability in autism (Mottron & Burack, 2001), autistic individuals outperform typically developing population in a variety of low-level perceptual tasks.