Magnuson James S, Nusbaum Howard C
Department of Psychology, University of Connecticut, Storrs, CT 06269-1020, USA.
J Exp Psychol Hum Percept Perform. 2007 Apr;33(2):391-409. doi: 10.1037/0096-1523.33.2.391.
Two talkers' productions of the same phoneme may be quite different acoustically, whereas their productions of different speech sounds may be virtually identical. Despite this lack of invariance in the relationship between the speech signal and linguistic categories, listeners experience phonetic constancy across a wide range of talkers, speaking styles, linguistic contexts, and acoustic environments. The authors present evidence that perceptual sensitivity to talker variability involves an active cognitive mechanism: Listeners expecting to hear 2 different talkers differing only slightly in average pitch showed performance costs typical of adjusting to talker variability, whereas listeners hearing the same materials but expecting a single talker or given no special instructions did not show these performance costs. The authors discuss the implications for understanding phonetic constancy despite variability between talkers (and other sources of variability) and for theories of speech perception. The results provide further evidence for active, controlled processing in real-time speech perception and are consistent with a model of talker normalization that involves contextual tuning.
两个说话者发出的同一个音素在声学上可能有很大差异，而他们发出的不同语音却可能几乎完全相同。尽管语音信号与语言类别之间缺乏这种不变性，但听众在面对广泛的说话者、说话风格、语言语境和声学环境时，仍能体验到语音的恒常性。作者提供了证据表明，对说话者变异性的感知敏感性涉及一种主动的认知机制：预期听到平均音高仅略有差异的两个不同说话者的听众，表现出了适应说话者变异性的典型表现成本，而听到相同材料但预期是同一个说话者或未得到特殊指示的听众则没有表现出这些表现成本。作者讨论了这些结果对于理解尽管说话者之间存在变异性（以及其他变异性来源）但语音仍具有恒常性的意义，以及对于语音感知理论的意义。这些结果为实时语音感知中的主动、受控处理提供了进一步的证据，并且与涉及情境调整的说话者归一化模型相一致。
