A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Summer, 2016 | Number 3, Volume 30

Inner ear defect may impair language processing in ASD

Researchers have detected an inner ear anomaly in children with autism spectrum disorders (ASD) that may impair their ability to recognize speech. 

Loisa Bennetto and colleagues enrolled 35 children with high-functioning autism and 42 age-matched neurotypical controls in their study. All participants were boys between 6 and 17 years of age with hearing classified as normal. 

The researchers tested the participants using miniature speaker/microphone earplugs that detect tiny sound emissions made by the inner ear’s outer hair cells in response to tones or clicks. If the cells are not working correctly, the earplugs fail to detect an emission. 

The researchers found that children with ASD had impaired responses to sounds in a specific frequency (1-2 kHz) that is important for processing speech. In addition, they found that the degree of impairment correlated with the severity of ASD symptoms.

“Auditory impairment has long been associated with developmental delay and other problems, such as language deficits,” Bennetto comments. “While there is no association between hearing problems and autism, difficulty in processing speech may contribute to some of the core symptoms of the disease.” 

Bennetto and her colleagues say their finding may pave the way for earlier diagnosis of autism and “can inform the development of approaches to correct auditory impairment with hearing aids or other devices that can improve the range of sounds the ear can process.”

Bennetto and colleagues found that children with ASD had difficulty responding to sounds in a specific frequency (1-2 kHz) that is important for speech. In addition, they found that the degree of impairment correlated with the severity of ASD symptoms.


Citations

“Children with autism spectrum disorder have reduced optoacoustic emissions at the 1 kHz midfrequency region,” Loisa Bennetto, Jessica M. Keith, Paul D. Allen, and Anne E. Luebke, Autism Research, July 12, 2016 (epub prior to print publication). Address: Anne E. Luebke, University of Rochester Medical Center, 601 Elmwood Avenue, Box 603, Rochester, NY 14642, anne_luebke@ urmc.rochester.edu. 

—and— 

“Hearing test may identify autism risk,” news release, University of Rochester, July 25, 2016.