Maastricht Brain Imaging Center, Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, the Netherlands.
Maastricht Brain Imaging Center, Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, the Netherlands.
Neuropsychologia. 2021 Jul 30;158:107889. doi: 10.1016/j.neuropsychologia.2021.107889. Epub 2021 May 12.
Statistical learning, or the ability to extract statistical regularities from the sensory environment, plays a critical role in language acquisition and reading development. Here we employed electroencephalography (EEG) with frequency-tagging measures to track the temporal evolution of speech-structure learning in individuals with reading difficulties due to developmental dyslexia and in typical readers. We measured EEG while participants listened to (a) a structured stream of repeated tri-syllabic pseudowords, (b) a random stream of the same isochronous syllables, and (c) a series of tri-syllabic real Dutch words. Participants' behavioral learning outcome (pseudoword recognition) was measured after training. We found that syllable-rate tracking was comparable between the two groups and stable across both the random and structured streams of syllables. More importantly, we observed a gradual emergence of the tracking of tri-syllabic pseudoword structures in both groups. Compared to the typical readers, however, in the dyslexic readers this implicit speech structure learning seemed to build up at a slower pace. A brain-behavioral correlation analysis showed that slower learners (i.e., participants who were slower in establishing the neural tracking of pseudowords) were less skilled in phonological awareness. Moreover, those who showed stronger neural tracking of real words tended to be less fluent in the visual-verbal conversion of linguistic symbols. Taken together, our study provides an online neurophysiological approach to track the progression of implicit learning processes and gives insights into the learning difficulties associated with dyslexia from a dynamic perspective.
统计学习，或从感官环境中提取统计规律的能力，在语言习得和阅读发展中起着关键作用。在这里，我们采用脑电图（EEG）与频率标记测量相结合的方法，跟踪有阅读障碍（发展性阅读障碍）和典型阅读者个体在言语结构学习中的时间演变。在参与者听（a）重复的三音节伪词的结构化流，（b）相同等时音节的随机流和（c）一系列三音节真实荷兰语单词时，我们测量了 EEG。在训练后，我们测量了参与者的行为学习结果（伪词识别）。我们发现，两组之间的音节率跟踪相当，并且在随机和结构化音节流中都很稳定。更重要的是，我们在两组中都观察到了对三音节伪词结构的跟踪逐渐出现。然而，与典型读者相比，在阅读障碍者中，这种隐式言语结构学习似乎进展较慢。脑行为相关分析表明，学习较慢的人（即，在建立伪词神经跟踪方面较慢的参与者）在语音意识方面的技能较差。此外，那些对真实单词的神经跟踪较强的人往往在语言符号的视觉-语言转换方面不太流利。总之，我们的研究提供了一种在线神经生理学方法来跟踪隐式学习过程的进展，并从动态的角度深入了解与阅读障碍相关的学习困难。
