title: Association of auditory steady state responses with perception of temporal modulations and speech in noise.
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.
authors.affiliation: AWH Special College, Payyanakkal, Kozhikode, Kerala 673 003, India.
authors.forename: Venugopal
authors.initials: V
authors.lastname: Manju
authors.affiliation: Department of Speech & Hearing, School of Allied Health Sciences, Manipal University, Manipal, Karnataka 576 104, India.
authors.forename: Kizhakke Kodiyath
authors.initials: KK
authors.lastname: Gopika
authors.affiliation: Department of Audiology & Speech Language Pathology, Kasturba Medical College, Manipal University, Mangalore, Karnataka 575 001, India.
authors.forename: Pitchai Muthu
authors.initials: PM
authors.lastname: Arivudai Nambi