Kent R D, Kent J F, Duffy J R, Thomas J E, Weismer G, Stuntebeck S
University of Wisconsin-Madison, 53705-2280, USA.
J Speech Lang Hear Res. 2000 Oct;43(5):1275-89. doi: 10.1044/jslhr.4305.1275.
Although ataxic dysarthria has been studied with various methods in several languages, questions remain concerning which features of the disorder are most consistent, which speaking tasks are most sensitive to the disorder, and whether the different speech production subsystems are uniformly affected. Perceptual and acoustic data were obtained from 14 individuals (seven men, seven women) with ataxic dysarthria for several speaking tasks, including sustained vowel phonation, syllable repetition, sentence recitation, and conversation. Multidimensional acoustic analyses of sustained vowel phonation showed that the largest and most frequent abnormality for both men and women was a long-term variability of fundamental frequency. Other measures with a high frequency of abnormality were shimmer and peak amplitude variation (for both sexes) and jitter (for women). Syllable alternating motion rate (AMR) was typically slow and irregular in its temporal pattern. In addition, the energy maxima and minima often were highly variable across repeated syllables, and this variability is thought to reflect poorly coordinated respiratory function and inadequate articulatory/voicing control. Syllable rates tended to be slower for sentence recitation and conversation than for AMR, but the three rates were highly similar. Formant-frequency ranges during sentence production were essentially normal, showing that articulatory hypometria is not a pervasive problem. Conversational samples varied considerably across subjects in intelligibility and number of words/ morphemes in a breath group. Qualitative analyses of unintelligible episodes in conversation showed that these samples generally had a fairly well-defined syllable pattern but subjects differed in the degree to which the acoustic contrasts typical of consonant and vowel sequences were maintained. For some individuals, an intelligibility deficit occurred in the face of highly distinctive (and contrastive) acoustic patterns.
尽管针对共济失调性构音障碍，已经运用多种方法在多种语言中开展了研究，但关于该障碍的哪些特征最为一致、哪些言语任务对该障碍最为敏感，以及不同的言语产生子系统是否受到统一影响等问题依然存在。从14名患有共济失调性构音障碍的个体（7名男性，7名女性）身上获取了针对多项言语任务的感知和声学数据，这些任务包括持续元音发声、音节重复、句子朗诵和对话。对持续元音发声的多维声学分析表明，男性和女性最大且最常见的异常是基频的长期变异性。其他异常频率较高的指标包括：（男女均有的）声门起始时间抖动和峰值幅度变化，以及（女性的）基频微扰。音节交替运动速率（AMR）在时间模式上通常缓慢且不规则。此外，在重复音节中，能量最大值和最小值往往高度可变，这种变异性被认为反映了呼吸功能协调不佳以及发音/发声控制不足。句子朗诵和对话时的音节速率往往比AMR慢，但这三种速率非常相似。句子生成过程中的共振峰频率范围基本正常，表明发音运动减少并非普遍存在的问题。不同受试者的对话样本在可懂度以及呼吸组中的单词/语素数量方面差异很大。对对话中难以理解的片段进行定性分析表明，这些样本通常具有相当明确的音节模式，但受试者在保持辅音和元音序列典型声学对比的程度上存在差异。对于一些个体而言，即使面对高度独特（且具有对比性）的声学模式，仍会出现可懂度缺陷。
