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Auditory sensory processing in autism: a magnetoencephalographic study.

Franca Tecchio·Francesca Benassi·Filippo Zappasodi·Leonardo Emberti Gialloreti·Mark Palermo·Stefano Seri·Paolo Maria Rossini
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Abstract

BACKGROUND: Patients with autism show clinical features suggestive of abnormal processing of auditory and other sensory information. We hypothesized that low-functioning autistic subjects present abnormalities in discriminating simple auditory stimuli at sensory system preconscious stages of cortical processing. METHODS: To verify our hypothesis, we used magnetoencephalographic measurements of mismatch field (MMF), which reflects the detection of a change in the physical characteristics of a repetitive sound. Fourteen patients (aged 8-32 years) who met DSM-IV diagnostic criteria for autistic disorder participated in an auditory oddball experiment. Ten healthy participants matched for age and gender acted as control subjects. RESULTS: Significant differences in cerebral responses between patients and control subjects were recorded. Whereas control subjects showed a clearly identifiable MMF, with distinct generators in the M100 brain wave with regard to latency, position, and strength, no identifiable MMF was present in the autistic group. CONCLUSIONS: Our findings suggest that low-functioning autistic subjects present a dysfunction at preconscious stages of cortical auditory discrimination, playing a role in the abnormal processing of auditory sensory afferences. The attention independence of the MMF allows for exclusion of an effect related to impaired attention or task-related responses.

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Acoustic StimulationAdolescentAdultAuditory CortexAuditory PerceptionAutistic DisorderCase-Control StudiesCerebral CortexChildDiscrimination, PsychologicalFemaleHumansMagnetoencephalographyMaleJournal Article

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Franca Tecchio, Francesca Benassi, Filippo Zappasodi, Leonardo Emberti Gialloreti, Mark Palermo, Stefano Seri, Paolo Maria Rossini. 2003-09-15. Auditory sensory processing in autism: a magnetoencephalographic study.. https://doi.org/10.1016/s0006-3223(03)00295-6

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