Altered Voice Processing in Young Children with Autism and Delayed Language Development
January 12, 2018 | by Dena H. Friedman
Children with autism spectrum disorder (ASD) and delayed language development learn and experience their world differently than their typically developing peers. A recent Kanazawa University study reports that they children ages three to five in particular, also appear to process voices differently.
Symptoms of ASD are many and vary dramatically from individual to individual. Yuko Yoshimura, an assistant professor in the Research Center for Child Mental Development at Kanazawa University, says, ‘“for each various symptom, there should be a various brain pathophysiology. It is important to objectively detect them, and to lead children with ASD and their parents to appropriate support and intervention."’
The team, which included scientists from the Gunma Prefectural College of Health Science, the Health Administration Center at the University of Fukui, and the International Education Center at Kyushu University, used magnetoencephalography, customized for use in children, during which they wear helmets to measure the magnetic fields of their whole brains.
During the procedure, the inferior frontal and superior temporal areas, located in the brain's left hemisphere, were previously found to be structurally important for language processing. The researchers played a female voice speaking the Japanese sound, "ne," which usually prompts communicative exchange between mother and child. The word was repeated with different tones, each designed to invoke different emotional meanings, from negative to neutral to positive.
Scientists compared recordings of the wavelengths to those typically produced in individuals without ASD. The difference between the two productions is called the magnetic mismatch field, and typically indicates a recognition of change from a series of constant stimulation.
The team found significant differences in two distinct magnetic mismatch field regions, a first in children so young. Children with ASD had much lower magnetic mismatch fields in the left superior temporal area than those without ASD. However, children with ASD and delayed language development had larger magnetic mismatch fields in the left inferior frontal area than typically developing children and children with ASD who do not have delayed language development.
"’In the current child psychiatric field, diagnosis of developmental disorder is performed only by [the child's] behavioral features and their growth history, whereas the biological objective indicator is not included. The importance of individual characteristics including physiological and biological indicators is recently gaining world-wide recognition to realize appropriate treatment and care,"’ said Yoshimura. "Our study demonstrated the brain biological indicator which is related to early stage language acquisition in young children with autism spectrum disorder."
The child-customized magnetoencephalography system will be used to further study the physiological and biological indicators in young children with developmental disorders to evaluate brain function in a manner conducive their special needs.
"Our ultimate goal is to build a common, bright future for all children," Yoshimura said. "We hope that children with ASD will receive diagnosis properly based on behavioral features and biological characteristics at [an] earlier stage, and receive appropriate support and treatment corresponding to each individual brain feature."
Source: Kanazawa University. "Altered voice processing in young children with autism and delayed language development." ScienceDaily. www.sciencedaily.com/releases/2018/01/180110080541.htm (accessed January 11, 2018).