Weismer Gary, Yunusova Yana, Westbury John R
Department of Communicative Disorders, Waisman Center, University of Wisconsin-Madison, 53706, USA.
J Speech Lang Hear Res. 2003 Oct;46(5):1247-61. doi: 10.1044/1092-4388(2003/097).
Articulatory discoordination is often said to be an important feature of the speech production disorder in dysarthria, but little experimental work has been done to identify and specify the coordination difficulties. The present study evaluated the coordination of labial and lingual gestures for /u/ production in persons with Parkinson's disease (PD), amyotrophic lateral sclerosis (ALS), and in control participants. Both tongue backing/raising and reduction of the area enclosed by the lips can produce the characteristic low F2 of /u/. The timing of these articulatory gestures with respect to the acoustic target of a low F2 was inferred from X-ray microbeam data. Pellet motions of the tongue dorsum and lips revealed the timing of the lingual and labial gestures to be strongly linked together (synchronized), predictive of the temporal location of the lowest F2 within the vocalic nucleus, and scaled proportionately to the overall vowel duration in control participants. Somewhat surprisingly, essentially the same findings were obtained in the speakers with dysarthria. These relationships were noisier among the speakers with dysarthria, but the global synchronization patterns applied to all 3 groups. Further analyses revealed the synchronization to be less well defined and more variable across speakers with ALS, as compared to speakers with PD and the controls. Results are discussed relative to concepts of coordination in dysarthria.
构音失调常被认为是构音障碍中言语产生障碍的一个重要特征，但针对识别和明确协调困难的实验研究却很少。本研究评估了帕金森病（PD）、肌萎缩侧索硬化症（ALS）患者以及对照参与者在发/u/音时唇和舌动作的协调性。舌后缩/抬高以及唇部所围区域缩小均可产生/u/音特有的低F2值。这些构音动作相对于低F2声学目标的时间是根据X射线微束数据推断出来的。舌背和唇部的小球运动显示，舌和唇动作的时间紧密相连（同步），可预测元音核内最低F2的时间位置，且在对照参与者中与整个元音时长成比例缩放。有点令人惊讶的是，构音障碍患者也得到了基本相同的结果。在构音障碍患者中，这些关系的噪声更大，但整体同步模式适用于所有三组。进一步分析表明，与PD患者和对照者相比，ALS患者的同步性定义较差，且个体间差异更大。本文将结合构音障碍中的协调概念对结果进行讨论。
