Abstract

The subjects of this report are identical (monozygotic) twin boys who differ in auditory function. One has normal hearing; the other has a profound hearing loss bilaterally. These boys offered a rare opportunity to study the effects of hearing loss on vocal development with reasonable control over environmental and genetic factors. This initial report focuses on their vocal development over the sampled ages of 8, 12, and 15 months. Acoustic-phonetic differences in the babbling of the two boys were evident in the 8-month sample (the first recording opportunity), and some differences between them became greater over the succeeding samples at 12 and 15 months. The major differences were in the formant patterns of vocalic elements; the frequency of occurrence of fricatives, affricates, and trills; histograms of syllable type; and variation in vowel usage. The data hold implications for the early identification of infants at risk for communication disorder and for the understanding of auditory-motor processes in phonetic development during infancy.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.