The effects of unison production on speech fluency in people with aphasia

许多旨在改善失语症患者(PWAS)口语输出的治疗方法包括统一语音，让失语症患者与临床医生或录音一起说话。这项研究的目的是确定个人和刺激特征，以预测一致说话的益处程度，并调查这种益处的可能机制。这一知识很重要，因为了解谁从这种常用且潜在强大的治疗成分中受益，他们在哪些条件下受益，以及他们为什么受益，对于定制治疗以实现最大治疗效率至关重要。一致讲话使用两种不同的计时模式之一：(1)自然会话模式，用于日常对话；或(2)韵律模式，遵循基于节拍的计时框架，如歌曲或一些诗歌中。在任何一种情况下，准确地使一个人的语言与另一个人的语言一致(即，吸引一个人的语言)需要预测：必须在听到和处理来自另一个人的相应输入之前制定运动命令。自然的会话计时要求说话人利用句法知识与另一个人保持一致，而韵律模式允许说话人在不严重依赖句法知识的情况下预测语音计时。鉴于许多PWA处理句法的能力受损(即，语法错误)，我们假设大多数PWA将更多地受益于与具有格律与会话时间模式的句子一致发言。然而，PWA在语言、运动语言和计时技能上存在很大的异质性，因此节律和会话计时模式可能会在不同的个体之间产生不同程度的效果。这项研究的结果将展示个体特征和言语时机如何影响失语症患者是否从一致说话中受益，并将测试预测性加工是否如真实的言语夹带所证明的那样，对于实现一致言语产生的好处是必要的。

Many treatments designed to improve spoken output in persons with aphasia (PWAs) incorporate unison speech, having the person with aphasia speak along with the clinician or with a recording. The goal of this study is to determine the individual and stimulus characteristics that predict the degree of benefit from speaking in unison, and to investigate a possible mechanism for this benefit. This knowledge is important because understanding who benefits from this commonly used and potentially powerful therapy component, under which conditions they benefit, and why they do, is critical for customizing therapy for maximum therapeutic efficiency. Unison speech is conducted using one of two different timing patterns: (1) a natural conversational pattern, which is used in everyday conversations, or (2) a metrical pattern, which follows a beat-based timing framework, as in songs or some poems. In either case, precisely aligning one’s speech with that of another person (i.e., entraining one’s speech) requires prediction: motor commands must be formulated before the corresponding input from the other person has been heard and processed. While natural conversational timing requires the speaker to make use of syntactic knowledge to align with the other person, a metrical pattern allows a speaker to predict speech timing without relying heavily on syntactic knowledge. Given that many PWAs have an impaired ability to process syntax (i.e., agrammatism), we hypothesize that most PWAs will benefit more from speaking in unison to sentences with metrical vs. conversational timing patterns. However, there is great heterogeneity in linguistic, motor speech, and timing skills across PWAs, so metrical and conversational timing patterns are likely to have different degrees of effectiveness across individuals. Results from this study will demonstrate how individual characteristics and speech timing affect whether or not a person with aphasia benefits from speaking in unison, and will test whether predictive processing, as evidenced by true speech entrainment, is necessary for a benefit of unison speech production to be realized.