Neurobiology of Language, Max Planck Institut für Psycholinguistik Nijmegen, Netherlands ; Neurobiology of Language, Donders Institute for Brain, Cognition and Behaviour, Radboud University Nijmegen Nijmegen, Netherlands.
Institute of Neuroscience and Psychology, University of Glasgow Glasgow, Scotland.
Front Psychol. 2014 Oct 9;5:1129. doi: 10.3389/fpsyg.2014.01129. eCollection 2014.
Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words' rhyme consistency and the non-words' lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- vs. accuracy-related effects for our understanding of dyslexic word recognition.
发展性阅读障碍通常表现为单词识别准确性和一般处理速度的双重缺陷。虽然之前对阅读障碍者单词识别的研究可能受到速度-准确性权衡的影响，但本研究采用了一种新的眼动追踪任务，较少受到这种混淆的影响。参与者（10 名阅读障碍者和 12 名对照组）被要求看真实的单词刺激，同时忽略呈现的非单词刺激，同时记录他们的眼动。根据连续非线性函数对单词识别准确性随时间的提高进行建模。在被试内操纵了单词的押韵一致性和非单词的词汇性（不可发音、可发音、拟声词）。从模型拟合中得出的与速度相关的测量结果证实了阅读障碍者的处理速度普遍较慢，并在阅读障碍者和对照组中都显示出了押韵一致性效应。就整体错误率而言，阅读障碍者（而不是对照组）在不一致的押韵单词上表现出较低的准确性，这表明阅读障碍者对这些单词的表示存在缺陷。有趣的是，两个组在速度或准确性上都没有表现出拟声词效应，这可能会对这种效应在任务独立性方面的普遍性提出质疑。本研究结果表明，对于我们对阅读障碍者单词识别的理解，区分速度相关效应与准确性相关效应是很重要的。
