Department of Neurology, University Medicine Greifswald, Greifswald, Germany.
Department of Neurology, Charité Universitätsmedizin Berlin, Berlin, Germany.
PLoS One. 2020 Jun 4;15(6):e0233608. doi: 10.1371/journal.pone.0233608. eCollection 2020.
Decades of research have explored communication in cerebrovascular diseases by focusing on formulaic expressions (e.g., "Thank you"-"You're welcome"). This category of utterances is known for engaging primarily right-hemisphere frontotemporal and bilateral subcortical neural networks, explaining why left-hemisphere stroke patients with speech-motor planning disorders often produce formulaic expressions comparatively well. The present proof-of-concept study aims to confirm that using verbal cues derived from formulaic expressions can alleviate word-onset difficulties, one major symptom in apraxia of speech.
In a cross-sectional repeated-measures design, 20 individuals with chronic post-stroke apraxia of speech were asked to produce (i) verbal cues (e.g., /guː/) and (ii) subsequent German target words (e.g., "Tanz") with critical onsets (e.g., /t/). Cues differed, most notably, in aspects of formulaicity (e.g., stereotyped prompt: /guː/, based on formulaic phrase "Guten Morgen"; unstereotyped prompt: /muː/, based on non-formulaic control word "Mutig"). Apart from systematic variation in stereotypy and communicative-pragmatic embeddedness possibly associated with holistic language processing, cues were matched for consonant-vowel structure, syllable-transition frequency, noun-verb classification, meter, and articulatory tempo.
Statistical analyses revealed significant increases in correctly produced word onsets after verbal cues with distinct features of formulaicity (e.g., stereotyped versus unstereotyped prompts: p < 0.001), as reflected in large effect sizes (Cohen's dz ≤ 2.2).
The current results indicate that using preserved formulaic language skills can relieve word-onset difficulties in apraxia of speech. This finding is consistent with a dynamic interplay of left perilesional and right intact language networks in post-stroke rehabilitation and may inspire new treatment strategies for individuals with apraxia of speech.
几十年来的研究通过关注惯用表达（例如，“谢谢”-“不客气”）探索了脑血管疾病中的交流。这一类言语表达主要涉及右半球额颞和双侧皮质下神经网络，这也解释了为什么左半球言语运动计划障碍的中风患者通常能够相对较好地产生惯用表达。本概念验证研究旨在证实使用源自惯用表达的口头提示可以减轻言语失用的起始困难，这是言语失用的主要症状之一。
在一项横断面重复测量设计中，要求 20 名慢性中风后言语失用症患者产生（i）口头提示（例如，/guː/）和（ii）随后的德语目标词（例如，“Tanz”）的关键起始音（例如，/t/）。提示在显著方面有所不同，特别是在惯用性方面（例如，刻板提示：/guː/，基于惯用短语“Guten Morgen”；非刻板提示：/muː/，基于非惯用控制词“Mutig”）。除了与整体语言处理相关的可能具有系统性的刻板性和交际语用嵌入变化外，提示还在辅音-元音结构、音节过渡频率、名词-动词分类、韵律和发音速度方面进行了匹配。
统计分析显示，在使用具有明显惯用性特征的口头提示（例如，刻板提示与非刻板提示：p < 0.001）后，正确产生的单词起始音显著增加，这反映在较大的效应量（Cohen 的 dz ≤ 2.2）中。
当前的结果表明，使用保留的惯用语言技能可以减轻言语失用的起始困难。这一发现与中风后康复中左旁区损伤和右半球完整语言网络的动态相互作用一致，可能为言语失用症患者激发新的治疗策略。
