Bourqui M, Lancheros M, Assal F, Laganaro M
Faculty of Psychology and Educational Science, University of Geneva, Geneva, Switzerland.
Department of Clinical Neurosciences, Geneva University Hospital and Faculty of Medicine, Geneva, Switzerland.
Clin Linguist Phon. 2025 Feb;39(2):99-120. doi: 10.1080/02699206.2024.2345353. Epub 2024 May 1.
Speakers with motor speech disorders (MSD) present challenges in speech production, one of them being the difficulty to adapt their speech to different modes. However, it is unclear whether different types of MSD are similarly affected when it comes to adapting their speech to various communication contexts. This study investigates the encoding of speech modes in individuals with AoS following focal brain damage and in individuals with hypokinetic dysarthria (HD) secondary to Parkinson's disease. Participants with mild-to-moderate MSD and their age-matched controls performed a delayed production task of pseudo-words in two speech modes: normal and whispered speech. While overall accuracy did not differ significantly across speech modes, participants with AoS exhibited longer response latencies for whispered speech, reflecting difficulties in the initiation of utterances requiring an unvoiced production. In contrast, participants with HD showed faster response latencies for whispered speech, indicating that this speech mode is easier to encode/control for this population. Acoustic durations followed these same trends, with participants with AoS showing greater lengthening for whispered speech as compared to controls and to participants with HD, while participants with HD exhibited milder lengthening. Contrary to the predictions of speech production models, suggesting that speech mode changes might be particularly difficult in dysarthria, the present results suggest that speech mode adaptation rather seems particularly costly for participants with AoS.
患有运动性言语障碍（MSD）的患者在言语产生方面存在挑战，其中之一是难以使他们的言语适应不同的模式。然而，在使言语适应各种交流情境时，不同类型的MSD是否受到类似影响尚不清楚。本研究调查了局灶性脑损伤后患有失语症（AoS）的个体以及帕金森病继发的运动减少型构音障碍（HD）个体中言语模式的编码情况。患有轻度至中度MSD的参与者及其年龄匹配的对照组在两种言语模式下完成了伪词延迟产生任务：正常言语和低语。虽然总体准确率在不同言语模式之间没有显著差异，但患有AoS的参与者在低语时表现出更长的反应潜伏期，这反映了在开始需要清音产生的言语时存在困难。相比之下，患有HD的参与者在低语时表现出更快的反应潜伏期，表明这种言语模式对该人群来说更容易编码/控制。声学时长也呈现出相同的趋势，与对照组和患有HD的参与者相比，患有AoS的参与者在低语时表现出更大程度的延长，而患有HD的参与者延长程度较轻。与言语产生模型的预测相反，该模型认为言语模式变化在构音障碍中可能特别困难，目前的结果表明，言语模式适应对患有AoS的参与者来说似乎成本特别高。
