Vadinova Veronika, Buivolova Olga, Dragoy Olga, van Witteloostuijn Merel, Bos Laura S
University of Amsterdam, Postbus 1605, 1000 BP, Amsterdam, the Netherlands.
HSE University, Staraya Basmannaya st. 21/4, office 510, 105066, Moscow, Russia.
Neuropsychologia. 2020 Oct;147:107591. doi: 10.1016/j.neuropsychologia.2020.107591. Epub 2020 Sep 3.
Implicit-statistical learning (ISL) research investigates whether domain-general mechanisms are recruited in the linguistic processes that require manipulation of patterned regularities (e.g. syntax). Aphasia is a language disorder caused by focal brain damage in the left fronto-temporal-parietal network. Research shows that people with aphasia (PWA) with frontal lobe lesions manifest convergent deficits in syntax and ISL mechanisms. So far, ISL mechanisms in PWA with temporal or parietal lobe lesions have not been systematically investigated.
We investigated two complementary hypotheses: 1) the anatomical hypothesis, that PWA with frontal lesions display more severely impaired ISL abilities than PWA with posterior lesions and 2) the behavioural hypothesis, that the magnitude of impairment in ISL mechanisms correlates to syntactic deficits in aphasia.
We tested 13 PWA, 5 with frontal lesions and 8 with posterior lesions, and 11 non-brain-damaged controls on a visual statistical learning (VSL) task. In addition, all PWA completed several linguistic tasks. Reaction times, obtained in the VSL task, were analyzed using linear mixed-effects model. Correlational statistics were used to assess the relationship between VSL task performance and linguistic measures.
We did not find support for the anatomical hypothesis as patients with spared frontal regions also manifested impaired ISL mechanisms. This is attributed to a) ISL mechanisms being vulnerable to other cognitive dysfunctions and/or b) ISL mechanisms anatomically extending to the posterior brain regions. Notably, ISL mechanisms were impaired, but not absent in aphasia. With regards to the behavioural hypothesis, we provide empirical evidence of correlation between ISL mechanisms and syntactic, but not lexical impairment in aphasia. We discuss both the theoretical contributions to the debate of domain-independence of ISL mechanisms and clinical implications for implicit language therapy.
内隐统计学习（ISL）研究旨在探究在需要处理模式规律性（如句法）的语言过程中，是否会调用通用领域机制。失语症是一种由左侧额颞顶叶网络局灶性脑损伤引起的语言障碍。研究表明，额叶受损的失语症患者（PWA）在句法和ISL机制方面存在趋同缺陷。到目前为止，颞叶或顶叶受损的PWA的ISL机制尚未得到系统研究。
我们研究了两个互补的假设：1）解剖学假设，即额叶受损的PWA比后叶受损的PWA表现出更严重受损的ISL能力；2）行为假设，即ISL机制的受损程度与失语症中的句法缺陷相关。
我们对13名PWA（5名额叶受损，8名后叶受损）和11名非脑损伤对照者进行了视觉统计学习（VSL）任务测试。此外，所有PWA都完成了几项语言任务。使用线性混合效应模型分析VSL任务中获得的反应时间。相关统计用于评估VSL任务表现与语言测量之间的关系。
我们没有找到对解剖学假设的支持，因为额叶区域未受损的患者也表现出受损的ISL机制。这归因于：a）ISL机制易受其他认知功能障碍影响和/或b）ISL机制在解剖学上延伸到后脑区域。值得注意的是，ISL机制受损，但在失语症中并非不存在。关于行为假设，我们提供了ISL机制与失语症中的句法缺陷而非词汇缺陷之间存在相关性的实证证据。我们讨论了对ISL机制领域独立性辩论的理论贡献以及对隐性语言治疗的临床意义。
