Description

Many behavioural theories describe Autism Spectrum Disorder (ASD) as having

roots as a social disorder. However, our research adds to previous studies showing that

those with ASD with normal intelligence have perceptual problems that affect their social

functioning. We report that those with ASD perform worse than controls in all of our

speech tasks that measure the ability to filter speech in noise, specialization for native

speech sound categories, and audio-visual integration of speech sounds. Those with ASD

also performed worse on tasks measuring specialization for native musical meters, but

not on tasks measuring the use of absolute pitch or knowledge of tonal harmony. This

research is important because little is known about some of these areas of auditory

processing. Thus, our battery forms a profile in which to understand speech and musical

processing in ASD. This research also provides some explanation for why perceptual

areas that develop early instead of late are most impaired in ASD, which can have

implications for remediation. Besides perceptual problems, we found in other research

that those with ASD have abnormal prosody, which varies according to language ability.

We report that those with Autism Moderate Language Functioning (A-moderateL) use a

restricted pitch range relative to those with Autism High Language Functioning (AhighL)

and controls, whereas those with A-highL use a larger pitch range relative to those

with A-moderateL and controls.