Dr. Andrea Warner-Czyz, an assistant professor at the Callier Center for Communication Disorders in the School of Behavioral and Brain Sciences, recently wrote an article in the Journal of the Acoustical Society of America that found infants hear speech differently than adults.
Two to three children out of 1,000 are born deaf, but cochlear implants, a technology that improves the odds of these children hearing, are becoming available to them at younger ages.
A cochlear implant with more than eight or nine channels does not necessarily improve the hearing of speech in adults. This study is one of the first to examine how this signal degradation affects hearing speech in infants.
Normal hearing babies participated in a test during which they heard speech sounds normally or as though the sounds had been processed through a 16- or 32-channel cochlear implant. The infants responded the same way to the 32-channel processed sounds as to the normal speech sounds; however, they could not tell the difference between the sounds processed as though through a 16-channel cochlear implant.
The researcher concluded these results suggest that 6-month-old infants need less distortion and more frequency information than older children and adults to discriminate speech. Warner-Czyz recommends clinicians take these developmental differences into account when working with very young cochlear implant recipients.
Article: “Vowel discrimination by hearing infants as a function of number of spectral channels”
