[Relationships between electrophysiological characteristic of speech evoked auditory brainstem response and Mandarin monosyllable discriminative ability at different hearing impairment].
OBJECTIVE
To investigate the relationships between electrophysiological characteristic of speech evoked auditory brainstem response(s-ABR) and Mandarin phonetically balanced maximum(PBmax) at different hearing impairment, so as to provide more clues for the mechanism of speech cognitive behavior.


METHODS
Forty-one ears in 41 normal hearing adults(NH), thirty ears in 30 conductive hearing loss patients(CHL) and twenty-seven ears in 27 sensorineural hearing loss patients(SNHL) were included in present study. The speech discrimination scores were obtained by Mandarin phonemic-balanced monosyllable lists via speech audiometric software. Their s-ABRs were recorded with speech syllables /da/ with the intensity of phonetically balanced maximum(PBmax). The electrophysiological characteristic of s-ABR, as well as the relationships between PBmax and s-ABR parameters including latency in time domain, fundamental frequency(F0) and first formant(F1) in frequency domain were analyzed statistically.


RESULTS
All subjects completed good speech perception tests and PBmax of CHL and SNHL had no significant difference (P>0.05), but both significantly less than that of NH (P<0.05). While divided the subjects into three groups by 90%<PBmax≤100%, 80%<PBmax≤90% and PBmax≤80%, the results showed that all subjects decreased amplitudes of F0 and F1, and increased latency of feature peaks as PBmax reduced. In the same PBmax group, latency of feature peaks increased and amplitudes of F0 and F1 decreased from SNHL, CHL to NH. All subjects showed strongest significant positive correlation between amplitudes of F0 and F1with PBmax respectively, as well as significant negative correlation between latencies of all the feature peaks with PBmax. A stepwise regression analysis equation displayed that the sum of latencies of peak A and F, and amplitudes of F0 and F1 attributed to PBmax reached 76%, and their beta coefficient decreased from amplitudes of F0 and amplitudes of F1, latencies of peak F to latencies of peak A.


CONCLUSIONS
These electrophysiological characteristics of s-ABR showed closely and stably associated with Mandarin monosyllable discriminative abilities at different hearing impairment. Some electrophysiological characteristics such as amplitudes of F0 and F1, latencies of peak F and A may play more important roles in speech recognition assess, which may be applied combined or separately to further investigation of speech perception and temporal processing abilities.
Department of Otorhinolaryngology Head and Neck Surgery, Guangdong No.2 Provincial People's Hospital, Guangzhou 510317, China.
Q Y
QY
Fu
Department of Otorhinolaryngology Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
Y
Y
Liang
School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
A
A
Zou
School of Biomedical Engineering, Southern Medical University, Guangzhou 510515, China.
T
T
Wang
Department of Otorhinolaryngology Head and Neck Surgery, Guangdong No.2 Provincial People's Hospital, Guangzhou 510317, China.
X D
XD
Zhao
Department of Otorhinolaryngology Head and Neck Surgery, Guangdong No.2 Provincial People's Hospital, Guangzhou 510317, China.
J
J
Wan
D000328:Adult; D001302:Audiometry, Speech; D002681:China; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology*; D006314:Hearing Loss, Conductive / Q000503:physiopathology*; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology*; D006801:Humans; D013060:Speech; D013067:Speech Perception