Manju Venugopal, Gopika Kizhakke Kodiyath, Arivudai Nambi Pitchai Muthu
AWH Special College, Payyanakkal, Kozhikode, Kerala 673 003, India.
Department of Speech & Hearing, School of Allied Health Sciences, Manipal University, Manipal, Karnataka 576 104, India.
ISRN Otolaryngol. 2014 Apr 14;2014:374035. doi: 10.1155/2014/374035. eCollection 2014.
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.
语音中的幅度调制为语音感知传递重要的声学信息。听觉稳态反应(ASSR)被认为是幅度调制感知的生理相关指标。目前关于ASSR与调制检测能力以及语音感知之间关联的研究有限。在两个实验中研究了调制检测阈值(MDT)以及噪声中的语音感知与ASSR的相关性。30名听力正常的个体和11名年龄在18至24岁之间的听力正常个体分别参与了实验1和实验2。在第一个实验中,使用ASSR和行为方法在60赫兹、80赫兹和120赫兹的调制频率下测量MDT。通过估计引发ASSR所需的最小调制深度(ASSR-MDT)来获得ASSR阈值。在所有调制频率下,行为MDT与ASSR-MDT之间均呈正相关。在第二个实验中,记录了四个不同频率范围(30 - 40赫兹、40 - 50赫兹、50 - 60赫兹和60 - 70赫兹)的幅度调制(AM)扫描的ASSR。使用阶梯法估计噪声中的语音识别阈值(SRTn)。在30 - 40赫兹频率范围内的AM扫描的ASSR幅度与SRTn之间呈正相关。当前研究结果表明,ASSR提供了关于时间调制和语音感知的大量信息。