Division of Neuroscience and Experimental Psychology, University of Manchester, Manchester Academic Health Science Centre, Oxford Road, Manchester, UK.
MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK.
Sci Rep. 2021 Feb 4;11(1):3168. doi: 10.1038/s41598-021-82809-w.
Aphasia affects at least one third of stroke survivors, and there is increasing awareness that more fundamental deficits in auditory processing might contribute to impaired language performance in such individuals. We performed a comprehensive battery of psychoacoustic tasks assessing the perception of tone pairs and sequences across the domains of pitch, rhythm and timbre in 17 individuals with post-stroke aphasia and 17 controls. At the level of individual differences we demonstrated a correlation between metrical pattern (beat) perception and speech output fluency with strong effect (Spearman's rho = 0.72). This dissociated from more basic auditory timing perception, which did not correlate with output fluency. This was also specific in terms of the language and cognitive measures, amongst which phonological, semantic and executive function did not correlate with beat detection. We interpret the data in terms of a requirement for the analysis of the metrical structure of sound to construct fluent output, with both being a function of higher-order "temporal scaffolding". The beat perception task herein allows measurement of timing analysis without any need to account for motor output deficit, and could be a potential clinical tool to examine this. This work suggests strategies to improve fluency after stroke by training in metrical pattern perception.
失语症影响至少三分之一的中风幸存者，人们越来越意识到，听觉处理的更基本缺陷可能导致此类个体语言表现受损。我们对 17 名中风后失语症患者和 17 名对照者进行了一系列全面的心理声学任务，评估了音高、节奏和音色领域中对音对和序列的感知。在个体差异水平上，我们证明了韵律模式（节拍）感知与言语输出流畅度之间存在相关性，具有很强的效应（Spearman's rho = 0.72）。这与更基本的听觉时间感知不同，后者与输出流畅度无关。从语言和认知测量来看，这也是特定的，其中语音、语义和执行功能与节拍检测不相关。我们根据分析声音的韵律结构以构建流畅输出的要求来解释这些数据，这两者都是高阶“时间结构”的功能。本文中的节拍感知任务允许在无需考虑运动输出缺陷的情况下测量时间分析，并且可能是一种潜在的临床工具来检查这一点。这项工作通过在韵律模式感知方面的训练，提出了改善中风后流畅度的策略。
