Van Tasell D J, Greenfield D G, Logemann J J, Nelson D A
Department of Communication Disorders, University of Minnesota, Minneapolis 55455.
J Acoust Soc Am. 1992 Sep;92(3):1247-57. doi: 10.1121/1.403920.
Limited consonant phonemic information can be conveyed by the temporal characteristics of speech. In the two experiments reported here, the effects of practice and of multiple talkers on identification of temporal consonant information were evaluated. Naturally produced /aCa/disyllables were used to create "temporal-only" stimuli having instantaneous amplitudes identical to the natural speech stimuli, but flat spectra. Practice improved normal-hearing subjects' identification of temporal-only stimuli from a single talker over that reported earlier for a different group of unpracticed subjects [J. Acoust. Soc. Am. 82, 1152-1161 (1987)]. When the number of talkers was increased to six, however, performance was poorer than that observed for one talker, demonstrating that subjects had been able to learn the individual stimulus items derived from the speech of the single talker. Even after practice, subjects varied greatly in their abilities to extract temporal information related to consonant voicing and manner. Identification of consonant place was uniformly poor in the multiple-talker situation, indicating that for these stimuli consonant place is cued via spectral information. Comparison of consonant identification by users of multi-channel cochlear implants showed that the implant users' identification of temporal consonant information was largely within the range predicted from the normal data. In the instances where the implant users were performing especially well, they were identifying consonant place information at levels well beyond those predicted by the normal-subject data. Comparison of implant-user performance with the temporal-only data reported here can help determine whether the speech information available to the implant user consists of entirely temporal cues, or is augmented by spectral cues.
语音的时间特征可以传达有限的辅音音位信息。在本文报道的两个实验中，评估了练习和多个说话者对时间辅音信息识别的影响。使用自然产生的/aCa/双音节词来创建“仅时间”刺激，其瞬时幅度与自然语音刺激相同，但频谱平坦。练习提高了听力正常的受试者对来自单个说话者的仅时间刺激的识别能力，超过了之前报道的另一组未练习受试者的识别能力[《美国声学学会杂志》82, 1152 - 1161 (1987)]。然而，当说话者数量增加到六个时，表现比单个说话者时更差，这表明受试者能够学习从单个说话者的语音中提取的各个刺激项。即使经过练习，受试者在提取与辅音发声和发音方式相关的时间信息的能力上仍有很大差异。在多个说话者的情况下，辅音位置的识别普遍较差，这表明对于这些刺激，辅音位置是通过频谱信息来提示的。多通道人工耳蜗植入使用者的辅音识别比较表明，植入使用者对时间辅音信息的识别在很大程度上处于根据正常数据预测的范围内。在植入使用者表现特别好的情况下，他们识别辅音位置信息的水平远远超过正常受试者数据预测的水平。将植入使用者的表现与本文报道的仅时间数据进行比较，可以帮助确定植入使用者可用的语音信息是完全由时间线索组成，还是由频谱线索增强。
