Liu Huei-Mei, Tsao Feng-Ming, Kuhl Patricia K
Department of Special Education, National Taiwan Normal University, Taiwan 98195.
J Acoust Soc Am. 2005 Jun;117(6):3879-89. doi: 10.1121/1.1898623.
The purpose of this study was to examine the effect of reduced vowel working space on dysarthric talkers' speech intelligibility using both acoustic and perceptual approaches. In experiment 1, the acoustic-perceptual relationship between vowel working space area and speech intelligibility was examined in Mandarin-speaking young adults with cerebral palsy. Subjects read aloud 18 bisyllabic words containing the vowels /i/, /a/, and /u/ using their normal speaking rate. Each talker's words were identified by three normal listeners. The percentage of correct vowel and word identification were calculated as vowel intelligibility and word intelligibility, respectively. Results revealed that talkers with cerebral palsy exhibited smaller vowel working space areas compared to ten age-matched controls. The vowel working space area was significantly correlated with vowel intelligibility (r=0.632, p<0.005) and with word intelligibility (r=0.684, p<0.005). Experiment 2 examined whether tokens of expanded vowel working spaces were perceived as better vowel exemplars and represented with greater perceptual spaces than tokens of reduced vowel working spaces. The results of the perceptual experiment support this prediction. The distorted vowels of talkers with cerebral palsy compose a smaller acoustic space that results in shrunken intervowel perceptual distances for listeners.
本研究的目的是使用声学和感知方法，考察元音工作空间减小对构音障碍患者言语可懂度的影响。在实验1中，研究了患有脑瘫的普通话年轻成年人中元音工作空间面积与言语可懂度之间的声学-感知关系。受试者以正常语速大声朗读18个包含元音/i/、/a/和/u/的双音节词。每个受试者的词由三名正常听众进行识别。正确识别元音和词的百分比分别计算为元音可懂度和词可懂度。结果显示，与十名年龄匹配的对照组相比，患有脑瘫的受试者表现出更小的元音工作空间面积。元音工作空间面积与元音可懂度显著相关（r = 0.632，p < 0.005），与词可懂度也显著相关（r = 0.684，p < 0.005）。实验2考察了元音工作空间扩大的样本是否比元音工作空间减小的样本被感知为更好的元音范例，并且具有更大的感知空间。感知实验的结果支持了这一预测。患有脑瘫的受试者的扭曲元音构成了一个较小的声学空间，导致听众的元音间感知距离缩小。
