Department of Communicative Disorders and Sciences, University at Buffalo, NY.
School of Communication Sciences and Disorders, Western University, London, Ontario, Canada.
J Speech Lang Hear Res. 2021 Nov 8;64(11):4096-4123. doi: 10.1044/2021_JSLHR-21-00160. Epub 2021 Sep 28.
Purpose The purpose of this study was to quantify changes in acoustic distinctiveness in two groups of talkers with Parkinson's disease as they modify across a wide range of speaking rates. Method People with Parkinson's disease with and without deep brain stimulation and older healthy controls read 24 carrier phrases at different speech rates. Target nonsense words in the carrier phrases were designed to elicit stop consonants and corner vowels. Participants spoke at seven self-selected speech rates from very slow to very fast, elicited via magnitude production. Speech rate was measured in absolute words per minute and as a proportion of each talker's habitual rate. Measures of segmental distinctiveness included a temporal consonant measure, namely, voice onset time, and a spectral vowel measure, namely, vowel articulation index. Results All talkers successfully modified their rate of speech from slow to fast. Talkers with Parkinson's disease and deep brain stimulation demonstrated greater baseline speech impairment and produced smaller proportional changes at the fast end of the continuum. Increasingly slower speaking rates were associated with increased temporal contrasts (voice onset time) but not spectral contrasts (vowel articulation). Faster speech was associated with decreased contrasts in both domains. Talkers with deep brain stimulation demonstrated more aberrant productions across all speaking rates. Conclusions Findings suggest that temporal and spectral segmental distinctiveness are asymmetrically affected by speaking rate modifications in Parkinson's disease. Talkers with deep brain stimulation warrant further investigation with regard to speech changes they make as they adjust their speaking rate.
目的 本研究的目的是量化两组帕金森病患者在语速大范围变化时的语音区分度变化。
方法 患有帕金森病且未接受深部脑刺激治疗的患者和健康老年对照组以 24 个载波短语在不同语速下阅读。载波短语中的目标无意义词旨在引出塞音和角元音。参与者以 7 种自我选择的语速（从非常慢到非常快）说话，通过幅度产生来引出。语速以每分钟的绝对字数和每个说话者的习惯语速的比例来衡量。音段区分度的度量包括音段时间测量，即嗓音起始时间，和音段频谱测量，即元音发音指数。
结果 所有说话者都成功地从慢语速调整到快语速。患有帕金森病和深部脑刺激的说话者显示出更大的基线语音障碍，并在连续体的快端产生较小的比例变化。语速逐渐变慢与时间对比（嗓音起始时间）增加有关，但与频谱对比（元音发音指数）无关。更快的语速与两个领域的对比减少有关。深部脑刺激的说话者在所有语速下表现出更多的异常发音。
结论 研究结果表明，帕金森病患者的语音区分度在语速变化时，时间和频谱音段区分度不对称地受到影响。深部脑刺激的说话者需要进一步研究他们在调整语速时所做的语音变化。
