Auditory encoding abnormalities in children with autism spectrum disorder suggest delayed development of auditory...

Area of Science:

• Neuroscience
• Developmental Psychology
• Audiology

Background:

• Children with autism spectrum disorder (ASD) exhibit auditory abnormalities, including delayed responses and atypical brain activity in the superior temporal gyrus (STG).
• These auditory differences are linked to abnormal brain maturation processes.
• Understanding age-related changes in brain activity is crucial for comprehending ASD development.

Purpose of the Study:

• To investigate the association between age and auditory neural activity in the STG.
• To compare time-domain and time-frequency neural activity in typically developing children (TDC) and children with ASD.
• To identify maturational differences in auditory processing between TDC and ASD.

Main Methods:

• Magnetoencephalography (MEG) was used to record brain activity in 63 TDC and 52 children with ASD (ages 6-14).
• Auditory stimuli (500- and 1000-Hz tones) were presented binaurally.
• Source modeling of the STG allowed for analysis of time-domain (M50, M100, M200) and time-frequency (total power, inter-trial coherence) measures.

Main Results:

• Children with ASD showed a right STG M100 latency delay compared to TDC.
• Increased pre- to post-stimulus power in the 4- to 16-Hz range was observed in the STG of children with ASD.
• Typically developing children exhibited greater post-stimulus inter-trial coherence in the right STG compared to children with ASD.
• Maturational delays in ASD were indicated by age-related differences in M200 activity and atypical hemispheric asymmetries in M50 and M100 responses.

Conclusions:

• The findings suggest maturational abnormalities in the primary and secondary auditory areas of children with ASD.
• Delayed development of the auditory processing system is hypothesized in ASD.
• Longitudinal studies are recommended to investigate the maturation of auditory network activity in ASD.