To date, the dynamics of information processing for Chinese visual word recognition has not been well elucidated. A key to understanding the different time courses of orthographic, semantic, and morphological activations in Chinese visual word recognition is to identify when and how the brain processes the various information at different stages.

In a study published in Cognitive Neurodynamics (2021 IF: 5.08), a  CCBS research team led by Prof. Zhen Yuan, collaborating with Prof. Juan Zhang, successfully unveiled the neural mechanism underlying lexicality effect in reading Chinese words. To the best of our knowledge, they are the first group to completely relate the dynamics of important brain events to the dynamics of precise Chinese visual word recognition-processing functions.

In this study, both behavioral and electrophysiological recording were performed to inspect the neural dynamics associated with lexicality effect by using a lexical decision task of reading Chinese disyllabic compound words, morphologically legal (pseudo-words) and illegal non-words. They demonstrated that an early event related potential (ERP) component N200 was firstly detected to be related to the visual identification of Chinese orthography. And then a process of semantic differentiation between the non-words and real words was carried out, in which the ERP component N400 was identified to be associated with lexicality effect. Further, a later ERP component P600 exhibited the difference between the non-words and pseudo-words, illustrating a re-analysis of word meaning or grammatical operation on Chinese morphological legality. Therefore, they argued that Chinese morphological structure might have an independent representation together with semantic representation in mental lexicon, emerging at the later stage of post-lexical processing. It is anticipated that the investigation into real words and different non-words will help establish a new method for improving the understanding of the neural mechanism of Chinese word reading.

Fig. 1 Grand-averaged ERP topographies of N200, N400, and P600 across three lexicality conditions, respectively. Topological plots showed the lexicality N200 effect in fronto-central and central regions, N400 effect in central region, and P600 effect in centro-parietal region.

Fig. 2 Three significant correlations between targeted ERP amplitudes (N200, N400, and P600) and behavioral data (RT and ACC): significant negative correlation between the lexicality N200 effect and real word RT (R= -0.53, p=0.014), between the lexicality N200 effect and pseudo-word ACC (R= -0.46, p=0.038), and between the lexicality N400 effect and real word ACC (R= -0.44, p=0.046). R denotes the Pearson’s correlation coefficient.

The study was led by Prof. Zhen Yuan and the main participant was Porf. Yuan’s PhD student Mr. Fei Gao. This work was jointly supported by the Macau Science and Technology Development Fund (Ref No.: FDCT 0020/2019/AMJ & FDCT 0011/2018/A1), Macao SAR Government Higher Education Fund (Ref No.: CP-UMAC-2020-01), Guangdong Provincial Fund (EF017/FHS-YZ/2021/GDSTCRSKTO), and RSKTO from the University of Macau.

Paper link: https://rdcu.be/czdTS 

Paper Information:

Fei Gao, Jianqin Wang, Chenggang Wu, Meng-yun Wang, Juan Zhang, Zhen Yuan. The neural dynamics associated with lexicality effect in reading single Chinese words, pseudo-words and non-words. Cognitive Neurodynamics, 2021, https://doi.org/10.1007/s11571-021-09720-y.