Auditory brainstem responses in adults with autism spectrum disorder

Area of Science:

• Neuroscience
• Audiology
• Developmental Psychology

Background:

• Autism spectrum disorder (ASD) is a complex neurodevelopmental condition.
• Auditory processing differences are frequently reported in individuals with ASD.
• The specific locus of auditory dysfunction, whether peripheral or central, remains under investigation.

Purpose of the Study:

• To compare auditory peripheral and brainstem functions between adults with ASD and neurotypical (NT) adults.
• To identify potential differences in auditory processing that may be associated with ASD.

Main Methods:

• Click-evoked auditory brainstem responses (ABRs) were recorded from 17 high-functioning ASD adults and 20 NT adults.
• Extensive stimulus presentations (6000) and both horizontal and vertical electrode montages were used for precise component evaluation.
• Analysis focused on early ABR components, including wave I, II, III, V, and summating potential (SP) latencies.

Main Results:

• No significant group differences were found in auditory brainstem response (ABR) wave latencies (I, II, III, V) or interpeak latencies (IPLs) using a vertical electrode montage.
• Adults with ASD exhibited significantly shortened summating potential (SP) latencies in the horizontal electrode montage compared to NT adults.
• Wave I latency in the horizontal montage showed no significant difference between ASD and NT groups.

Conclusions:

• Findings suggest that auditory processing abnormalities in adults with ASD may predominantly involve the peripheral auditory system rather than the brainstem.
• The observed peripheral auditory abnormality, specifically in SP latency, is associated with autism spectrum disorder.
• This research highlights the importance of evaluating peripheral auditory function in the context of ASD.