Department of Speech, Language, and Hearing Sciences, University of Florida, Gainesville, Florida 32611, USA.
J Voice. 2012 Nov;26(6):811.e1-7. doi: 10.1016/j.jvoice.2012.02.007. Epub 2012 Aug 24.
Essential tremor of the voice (ETV) is an involuntary intention tremor of the vocal folds that causes fluctuations in fundamental frequency (f(0)) and/or intensity leading to an unsteady voice. There is limited data on how different acoustic variables affect perception of severity of tremor.
The purpose of the study was to determine if systematic changes in f(0), rate or modulation frequency (f(f0m)), extent or depth of modulation (d(f0m)), and signal-to-noise ratio (SNR) affect perception of severity of tremor.
Vowel phonations of four speakers (two male and two female) with a clinical diagnosis of ETV were selected from the Kay Elemetrics Disordered Voice Database (Lincoln Park, NJ). A high fidelity speech vocoder (STRAIGHT; Kawahara, 1997) was used to synthesize the f(0) contour for each of these voices, which were varied in mean f(0), f(f0m), and d(f0m). The f(0) contour was modified 30 Hz above and below the mean f(0) for each speaker. f(f0m) ranged from 3 to 12 Hz in steps of 3 Hz. d(f0m) ranged from 2 to 32 Hz in steps of 6 Hz. Six (three experts and three naïve) listeners rated the "severity" of tremor on a seven-point rating scale.
Significant main effects and interactions were found between the study variables. Perceived severity of tremor increased with f(f0m) and d(f0m). There was no systematic effect of SNR on perceived tremor severity.
The perception of severity for steady-state tremor results from a complex interaction of multiple acoustic cues with d(f0m) acting as the primary acoustic cue.
声带性原发性震颤（ETV）是一种声带的不随意意向性震颤，会导致基频（f(0)）和/或强度的波动，从而导致声音不稳定。关于不同声学变量如何影响震颤严重程度的感知，数据有限。
本研究旨在确定 f(0)、速率或调制频率（f(f0m)）、调制深度（d(f0m)）和信噪比（SNR）的系统变化是否会影响对震颤严重程度的感知。
从 Kay Elemetrics 障碍性嗓音数据库（新泽西州林肯公园）中选择了四位患有 ETV 临床诊断的说话者的元音发音。使用高保真语音声码器（STRAIGHT；Kawahara，1997）为每个声音合成 f(0)轮廓，这些声音的平均 f(0)、f(f0m)和 d(f0m)有所不同。f(0)轮廓在每个说话者的平均 f(0)之上和之下都修改了 30Hz。f(f0m)在 3 到 12Hz 之间以 3Hz 的步长变化。d(f0m)在 2 到 32Hz 之间以 6Hz 的步长变化。六位（三位专家和三位新手）听众在七分制评分量表上对震颤的“严重程度”进行了评分。
在研究变量之间发现了显著的主效应和交互作用。震颤的感知严重程度随着 f(f0m)和 d(f0m)的增加而增加。SNR 对感知震颤严重程度没有系统的影响。
稳态震颤的严重程度感知是由多个声学线索的复杂相互作用产生的，d(f0m)是主要的声学线索。
