Table of Contents
ISRN Otolaryngology
Volume 2014, Article ID 374035, 8 pages
http://dx.doi.org/10.1155/2014/374035
Research Article

Association of Auditory Steady State Responses with Perception of Temporal Modulations and Speech in Noise

1AWH Special College, Payyanakkal, Kozhikode, Kerala 673 003, India
2Department of Speech & Hearing, School of Allied Health Sciences, Manipal University, Manipal, Karnataka 576 104, India
3Department of Audiology & Speech Language Pathology, Kasturba Medical College, Manipal University, Mangalore, Karnataka 575 001, India

Received 19 January 2014; Accepted 4 March 2014; Published 14 April 2014

Academic Editors: C. Y. Chien, K. Parham, M. Suzuki, and S. C. Winter

Copyright © 2014 Venugopal Manju et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Amplitude modulations in the speech convey important acoustic information for speech perception. Auditory steady state response (ASSR) is thought to be physiological correlate of amplitude modulation perception. Limited research is available exploring association between ASSR and modulation detection ability as well as speech perception. Correlation of modulation detection thresholds (MDT) and speech perception in noise with ASSR was investigated in twofold experiments. 30 normal hearing individuals and 11 normal hearing individuals within age range of 18–24 years participated in experiments 1 and 2, respectively. MDTs were measured using ASSR and behavioral method at 60 Hz, 80 Hz, and 120 Hz modulation frequencies in the first experiment. ASSR threshold was obtained by estimating the minimum modulation depth required to elicit ASSR (ASSR-MDT). There was a positive correlation between behavioral MDT and ASSR-MDT at all modulation frequencies. In the second experiment, ASSR for amplitude modulation (AM) sweeps at four different frequency ranges (30–40 Hz, 40–50 Hz, 50–60 Hz, and 60–70 Hz) was recorded. Speech recognition threshold in noise (SRTn) was estimated using staircase procedure. There was a positive correlation between amplitude of ASSR for AM sweep with frequency range of 30–40 Hz and SRTn. Results of the current study suggest that ASSR provides substantial information about temporal modulation and speech perception.