时域精细结构与包络信息在噪声下声调识别中的作用

目的 探讨时域精细结构信息(temporal fine structure,TFS)和时域包络信息(envelope,Env)在噪声下声调识别中的作用.方法 自行编制噪声下声调识别能力测试材料,对20例年龄19～30岁、母语为汉语普通话的听力正常人进行五种信噪比(SNR)条件下(SNR分别为-18、-12、-6、0、+...

The Contributions of Temporal Fine Structure and Envelope Information for Lexical Tone Identification in Noise

Objective To investigate the role of temporal fine structure(TFS)and envelope(Env)cues in tone perception in noise.Methods Twenty normal hearing listeners aged ranged from 19 to 30 yr(mean age=23.71 yr,SD=2.995)participated in this study(10 females,10 males).All participants were native speakers of Mandarin.The tone perception test used a word-based,four-alternative forced-choice test(4-AFC)paradigm controlled using custom MATLAB routines running on PCs.Targets and the masker were added at five different signal-to-noise ratios(SNRs=-18,-12,-6,0,+6 dB).Generalized Linear Model(GLM)was used to examine the effects of TFS and Env on tone recognition performance.Results①The tone-recognition performance improved as the SNRs in either TFS or E increased.Both TFS and E contributed significantly to tone recognition in various SNR.In the SSN conditions,the coefficients(β)of the GLM fitting for SNR in TFS,SNR in Env,and the interaction between SNRs in TFS and Env were 0.095(P<0.0001),0.070(P<0.0001)and-0.002(P<0.0001),respectively.In the TTB conditions,the coefficients(β)of the GLM fitting for SNR in TFS,SNR in Env,and the interaction between SNRs in TFS and Env were 0.052(P<0.0001),0.073(P<0.0001)and-0.0003(P=0.13),respectively.②When the SNRs in both TFS and Env were equal,the tonal perception results were increased withimproving SNR.The average tone-recognition scores were 27.6,60.2,82.1,93.9,and 94.7%correct in SSN conditions at SNR of-18,-12,-6,0,and+6 dB,respectively and were 53.5,72.0,86.4,92.7,and 95.0%correct in TTB conditions at the same SNR.Conclusion The present data have showed that both TFS and Env cues contributed to lexical tone perception in noise.Therefore,providing both TFS and Env in hearing devices such as cochlear implants should be beneficial for the hearing-impaired listeners in everyday noisy environment.