Children with autism process sounds differently

For the first time, an international team of researchers—including scientists from the HSE Centre for Language and Brain—combined magnetoencephalography and morphometric analysis in a single experiment to study children with Autism Spectrum Disorder (ASD). The study found that children with autism have more difficulty filtering and processing sounds, particularly in the brain region typically responsible for language comprehension. The study has been published in Cerebral Cortex.

Autism, or Autism Spectrum Disorder (ASD), is a group of neurodevelopmental conditions that affect how a person perceives themselves, relates to others, and communicates. These conditions can vary widely, but people with ASD often have difficulty perceiving and processing sounds—for example, distinguishing speech in noisy environments, adapting to loud stimuli, or ignoring repetitive noises. Research indicates that these difficulties are linked to the functioning of the primary auditory cortex—the part of the brain’s temporal lobe responsible for basic sound processing. However, the precise ways in which auditory processing impacts language and communication in individuals with ASD remain poorly understood.

To explore the link between sound perception and language difficulties in children with ASD, researchers from the HSE Centre for Language and Brain, together with colleagues from Russia, the USA, and New Zealand, conducted a comprehensive study. They combined two methods: magnetoencephalography (MEG), which tracks brain activity in response to specific stimuli with millisecond precision, and morphometric analysis based on structural MRI data, which examines both the quantitative and qualitative features of the auditory cortex—such as its volume, thickness, and the shape of its gyri.

The study included 40 children—20 with typical development and 20 with a confirmed diagnosis of ASD. While the children listened to simple sounds—short clicks—scientists recorded their brain activity. The researchers focused on three components of the brain’s auditory response: M50, M100, and M200, which occur 50, 100, and 200 milliseconds after the sound is presented. Each of these components reflects a different stage of processing, ranging from basic perception to filtering and comprehension.

The most significant differences were found in the M200 component, which is involved in processing and filtering repetitive sounds. In children with ASD, this signal was significantly weaker, particularly in the left hemisphere, which is typically responsible for auditory perception and comprehension.

Olga Dragoy

'We aimed to determine whether the perception of simple sounds is linked to language difficulties in children with ASD,' explains Olga Dragoy, Director of the HSE Centre for Language and Brain. 'Our results show that language difficulties in these children begin at a very early stage, when the brain first recognises and processes basic sounds.'

Anatomically, children with ASD exhibit two features: the auditory cortex in their left hemisphere is thinner, and the gyri are more curved and deeper. It was found that the more pronounced these differences, the greater difficulties children have with language comprehension and communication.

Alina Minnigulova

'The auditory cortex in the left, "linguistic" hemisphere helps children not only distinguish sounds but also learn to comprehend language and speak,' explains Alina Minnigulova, Research Fellow at the HSE Centre for Language and Brain. 'Perhaps it develops differently in children with ASD, which in turn affects their ability to comprehend language. Studying the relationship between auditory processing and language skills can aid in early diagnosis and the development of new educational and therapeutic approaches for children with ASD.'

The study was conducted with support from HSE University's Basic Research Programme within the framework of the Centres of Excellence project.