Laboratoire de Psychologie Cognitive, Aix-Marseille University & CNRS, France.
Joint Doctoral Program in Language and Communicative Disorders, San Diego State University & University of California, San Diego, United States.
Neuropsychologia. 2019 Jun;129:276-283. doi: 10.1016/j.neuropsychologia.2019.04.009. Epub 2019 Apr 16.
During reading, word recognition speed is influenced by the amount of orthographic overlap with surrounding words. The nature of this phenomenon is not understood: some theories attribute it to low-level visual operations (i.e., parafoveal feature detectors influencing foveal letter detectors), whereas other theories assume that orthographic processing (i.e., letter position coding and word activation) occurs across multiple words in parallel. To arbitrate between these theories, we used electroencephalography to reveal the time course of orthographic spatial integration in a lexical decision task. Foveal target words were flanked on each side by parafoveal words, manipulated across three conditions: repetition flankers (e.g. rock rock rock), unrelated flankers (step rock step) and a no-flanker condition. Linear mixed-effect models were constructed to analyze EEG data on a trial-by-trial basis. Word recognition was worse in the unrelated flanker condition than in the repetition and no-flanker conditions. This behavioral pattern was accompanied by increased negativity in the N250 and N400 windows, associated with the activation of sub-lexical and lexico-semantic representations, respectively. Crucially, the absence of effects prior to 200 ms post-stimulus onset provides evidence against the involvement of low-level visual processes. We conclude that orthographic spatial integration is driven by parallel processing of multiple words, which leads to the activation of a larger set of sub-lexical nodes and more difficult processing at the lexical level when those words are orthographically unrelated.
在阅读过程中，单词识别速度会受到与周围单词的正字法重叠量的影响。这种现象的本质尚不清楚：一些理论将其归因于低级视觉操作（即，旁视网膜特征探测器影响中央视网膜字母探测器），而其他理论则假设正字法处理（即，字母位置编码和单词激活）在多个单词中并行发生。为了在这些理论之间做出裁决，我们使用脑电图来揭示词汇决策任务中正字法空间整合的时间过程。中央视网膜目标词的每一侧都有旁视网膜词的侧翼，在三种条件下进行操纵：重复侧翼（例如，rock rock rock）、不相关侧翼（step rock step）和无侧翼条件。线性混合效应模型被构建来逐试分析 EEG 数据。在不相关的侧翼条件下，单词识别比重复和无侧翼条件差。这种行为模式伴随着 N250 和 N400 窗口中负性的增加，分别与亚词汇和词汇语义表示的激活有关。至关重要的是，在刺激后 200 毫秒之前没有效应的出现，这提供了反对低水平视觉过程参与的证据。我们得出结论，正字法空间整合是由多个单词的并行处理驱动的，这导致了更大的一组亚词汇节点的激活，并且当这些单词在正字法上不相关时，在词汇水平上的处理更加困难。
