Lee Shao-Hsuan, Torng Pao-Chuan, Lee Guo-She
Department of Speech Language Pathology and Audiology, National Taipei University of Nursing and Health Sciences, Taiwan.
School of Medicine, College of Medicine, National Yang Ming Chiao Tung University, Taiwan.
J Speech Lang Hear Res. 2022 May 11;65(5):1751-1766. doi: 10.1044/2022_JSLHR-21-00443. Epub 2022 Mar 30.
The spectral powers of the modulations of vocal fundamental frequency ( ) less than 3 Hz (low-frequency power, LFP) and between 3 and 8 Hz (middle-frequency power, MFP) had been established to indicate the audio-vocal feedback status and vocal efficiency of a speaker, and a resonant voice may enhance the auditory-vocal feedback. This study aims to determine whether the auditory feedback can be augmented by a forward and resonant voice and therefore contribute to the modulations of variability.
Vocal signals and accelerometric signals of lateral nasal cartilage were obtained from 27 healthy adults who, respectively, sustained vowels /a/ and /i/ with their habitual speaking voice and with a forward-focused voice under three auditory conditions: natural hearing (N0), high-level noise exposure (N90), and low-level noise exposure (N60). Nasal skin vibrations were measured using a nasal accelerometry to reflect voice resonance status. Vocal intensity and variability were also analyzed to show the auditory-vocal interactions under varied conditions of auditory feedback and voice resonance.
In both N0 and N90 conditions, forward-focused voice showed a significantly lower LFP than the speakers' habitual voice. In addition, LFP of would significantly increase during natural voice production as the voice feedback was greatly masked by high-intensity noise; however, with a forward-focused voice, the noise-induced variation in LFP was significantly decreased. Under N90, MFP significantly decreased during forward-focused voice production compared with that measured during natural voice production. The stability of modulations was not adversely affected by N60.
The results support the idea that vocalizing with a forward-focused voice enhance the auditory feedback of the speaker's own voice and, thus, reduce the variability of during sustained phonation, especially when vocalizing in the high noise condition.
已确定声带基频（）调制中低于3Hz的频谱功率（低频功率，LFP）以及3至8Hz之间的频谱功率（中频功率，MFP）可表明说话者的听觉-声音反馈状态和发声效率，并且共鸣嗓音可能会增强听觉-声音反馈。本研究旨在确定前位聚焦且共鸣的嗓音是否能增强听觉反馈，从而有助于调制的变异性。
从27名健康成年人获取了外侧鼻软骨的声音信号和加速度计信号，这些成年人分别在三种听觉条件下，即自然听力（N0）、高强度噪声暴露（N90）和低强度噪声暴露（N60）时，用其习惯性嗓音和前位聚焦嗓音持续发出元音/a/和/i/。使用鼻加速度计测量鼻皮肤振动以反映嗓音共鸣状态。还分析了发声强度和的变异性，以显示在不同听觉反馈和嗓音共鸣条件下的听觉-声音相互作用。
在N0和N90条件下，前位聚焦嗓音的LFP均显著低于说话者的习惯性嗓音。此外，在自然发声过程中，由于嗓音反馈被高强度噪声极大地掩盖，的LFP会显著增加；然而，使用前位聚焦嗓音时，噪声引起的LFP变化会显著降低。在N90条件下，与自然发声时相比，前位聚焦发声过程中的MFP显著降低。N60对调制的稳定性没有不利影响。
结果支持以下观点，即使用前位聚焦嗓音发声可增强说话者自身嗓音的听觉反馈，从而在持续发声过程中降低的变异性，尤其是在高噪声条件下发声时。
