PDF(Pubmed)
Abstract：
Most studies on word repetition have demonstrated that repeated stimuli yield reductions in brain activity. Despite the well-known repetition reduction effect, some literature reports repetition enhancements in electroencephalogram (EEG) activities. However, although studies of object and face recognition have consistently demonstrated both repetition reduction and enhancement effects, the results of repetition enhancement effects were not consistent in studies of visual word recognition. Therefore, the present study aimed to further investigate the repetition effect on the P200, an early event-related potential (ERP) component that indexes the coactivation of lexical candidates during visual word recognition. To achieve a high signal-to-noise ratio, EEG signals were decomposed into various modes by using the Hilbert-Huang transform. Results demonstrated a repetition enhancement effect on P200 activity in alpha-band oscillation and that lexicality and orthographic neighborhood size would influence the magnitude of the repetition enhancement effect on P200. These findings suggest that alpha activity during visual word recognition might reflect the coactivation of orthographically similar words in the early stages of lexical processing. Meantime, there were repetition reduction effects on ERP activities in theta-delta band oscillation, which might index that the lateral inhibition between lexical candidates would be omitted in repetition.
摘要：
大多数关于单词重复的研究表明，重复的刺激会减少大脑活动。尽管有众所周知的减少重复的效果，一些文献报道了脑电图（EEG）活动的重复增强。然而,尽管对物体和面部识别的研究一直证明了重复减少和增强效果，在视觉单词识别研究中，重复增强效果的结果不一致。因此,本研究旨在进一步研究对P200的重复效应，P200是一种早期事件相关电位（ERP）组件，可在视觉单词识别过程中对词汇候选项的共激活进行索引。为了实现高信噪比，使用Hilbert-Huang变换将EEG信号分解为各种模式。结果表明，在α波段振荡中，重复增强对P200活动的影响，词性和正交邻域大小会影响重复增强对P200的影响。这些发现表明，视觉单词识别过程中的alpha活动可能反映了在词汇处理的早期阶段拼字相似单词的共激活。同时,θ-δ波段振荡对ERP活动有重复减少效应，这可能表明在重复中将省略词汇候选之间的横向抑制。
