Department of Speech Hearing and Phonetic Sciences, UCL, London WC1N 1PF, UK; Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada.
Brain and Mind Institute, University of Western Ontario, London, Ontario N6A 3K7, Canada; School of Communication Sciences and Disorders, University of Western Ontario, London, Ontario N6G 1H1, Canada.
Hear Res. 2023 Mar 1;429:108704. doi: 10.1016/j.heares.2023.108704. Epub 2023 Jan 20.
Speech is more intelligible when it is spoken by familiar than unfamiliar people. If this benefit arises because key voice characteristics like perceptual correlates of fundamental frequency or vocal tract length (VTL) are more accurately represented for familiar voices, listeners may be able to discriminate smaller manipulations to such characteristics for familiar than unfamiliar voices. We measured participants' (N = 17) thresholds for discriminating pitch (correlate of fundamental frequency, or glottal pulse rate) and formant spacing (correlate of VTL; 'VTL-timbre') for voices that were familiar (participants' friends) and unfamiliar (other participants' friends). As expected, familiar voices were more intelligible. However, discrimination thresholds were no smaller for the same familiar voices. The size of the intelligibility benefit for a familiar over an unfamiliar voice did not relate to the difference in discrimination thresholds for the same voices. Also, the familiar-voice intelligibility benefit was just as large following perceptible manipulations to pitch and VTL-timbre. These results are more consistent with cognitive accounts of speech perception than traditional accounts that predict better discrimination.
当语音由熟悉的人而非陌生人发出时，语音的可理解度更高。如果这种优势源自于关键的声音特征（如基频的感知相关物或声道长度（VTL））能够更准确地代表熟悉的声音，那么听众可能能够更准确地区分熟悉声音与不熟悉声音在这些特征上的微小变化。我们测量了参与者（N=17）区分音高（基频相关物或声门脉冲率）和共振峰间隔（VTL 相关物；“VTL-音色”）的阈值，这些声音分别来自熟悉的人（参与者的朋友）和不熟悉的人（其他参与者的朋友）。正如预期的那样，熟悉的声音更具可理解性。然而，相同的熟悉声音的辨别阈值并没有更小。与不熟悉的声音相比，熟悉的声音具有更大的可理解性优势，但这种优势的大小与相同声音的辨别阈值差异无关。此外，在感知到音高和 VTL-音色发生变化后，熟悉声音的可理解性优势仍然很大。这些结果与传统的预测更好的辨别能力的理论解释相比，更符合语音感知的认知理论解释。
