The Effect of Hearing Loss on Identification of Asynchronous Double Vowels This study determined whether listeners with hearing loss received reduced benefits due to an onset asynchrony between sounds. Seven normal-hearing listeners and 7 listeners with hearing impairment (HI) were presented with 2 synthetic, steady-state vowels. One vowel (the late-arriving vowel) was 250 ms in duration, and the other (the early-arriving ... Research Article
Research Article  |   December 01, 2006
The Effect of Hearing Loss on Identification of Asynchronous Double Vowels
 
Author Affiliations & Notes
  • Jennifer J. Lentz
    Indiana University, Bloomington
  • Shavon L. Marsh
    St. John’s University, Jamaica, NY
  • Contact author: Jennifer J. Lentz, Department of Speech and Hearing Sciences, Indiana University, 200 S. Jordan Avenue, Bloomington, IN 47405. E-mail: jjlentz@indiana.edu.
Article Information
Hearing & Speech Perception / Hearing Disorders / Speech, Voice & Prosody / Hearing / Research Articles
Research Article   |   December 01, 2006
The Effect of Hearing Loss on Identification of Asynchronous Double Vowels
Journal of Speech, Language, and Hearing Research, December 2006, Vol. 49, 1354-1367. doi:10.1044/1092-4388(2006/097)
History: Received November 9, 2004 , Accepted May 1, 2006
 
Journal of Speech, Language, and Hearing Research, December 2006, Vol. 49, 1354-1367. doi:10.1044/1092-4388(2006/097)
History: Received November 9, 2004; Accepted May 1, 2006

This study determined whether listeners with hearing loss received reduced benefits due to an onset asynchrony between sounds. Seven normal-hearing listeners and 7 listeners with hearing impairment (HI) were presented with 2 synthetic, steady-state vowels. One vowel (the late-arriving vowel) was 250 ms in duration, and the other (the early-arriving vowel) varied in duration between 350 and 550 ms. The vowels had simultaneous offsets, and therefore an onset asynchrony between the 2 vowels ranged between 100 and 300 ms. The early-arriving and late-arriving vowels also had either the same or different fundamental frequencies. Increases in onset asynchrony and differences in fundamental frequency led to better vowel-identification performance for both groups, with listeners with HI benefiting less from onset asynchrony than normal-hearing listeners. The presence of fundamental frequency differences did not influence the benefit received from onset asynchrony for either group. Excitation pattern modeling indicated that the reduced benefit received from onset asynchrony was not easily predicted by the reduced audibility of the vowel sounds for listeners with HI. Therefore, suprathreshold factors such as loss of the cochlear nonlinearity, reduced temporal integration, and the perception of vowel dominance probably play a greater role in the reduced benefit received from onset asynchrony in listeners with HI.

Acknowledgments
This work was supported by Grant DC 005835 from the National Institute on Deafness and Other Communication Disorders and by a summer undergraduate research scholarship to Shavon Marsh by the McNair Scholars Program. We thank T. Beth Trainor-Hayes for assistance with data collection and Marjorie Leek, Larry Humes, and Michelle Molis for their valuable comments on this manuscript and assistance in interpreting the data.
Order a Subscription
Pay Per View
Entire Journal of Speech, Language, and Hearing Research content & archive
24-hour access
This Article
24-hour access