Chinese Character Features Facilitate Working Memory Updating: Evidence From the EEG

According to the multicomponent model of working memory (WM), the phonological loop serves to protect WM representations from interference through its phonological storage and rehearsal mechanisms, thereby enhancing performance on WM tasks. However, the neural mechanisms by which language knowledge facilitates WM remain unclear. The present study aims to explore how Chinese character features influence WM and to uncover the underlying mechanisms involved.

Using the 2-back task paradigm with both real and pseudo characters, we recorded behavioral and electroencephalogram (EEG) data from 33 participants (aged 18-24 years; 16 males). By employing a combination of event-related potential (ERP) and time-frequency analysis (TFA) techniques, we investigated differences in neural activity among participants as they engaged in the real character and pseudo-character 2-back tasks.

Behavioral results showed that the d-prime was higher and the reaction time was shorter for the real character 2-back task. The ERP results revealed that the P200 and P300 amplitudes were significantly smaller during the real character 2-back task than during the pseudo-character 2-back task. TFA results revealed that the event-related desynchronization (ERD) of alpha oscillations was significantly smaller during the real character task than during the pseudo-character task. There were no differences in theta activity.

The characteristics of Chinese characters influence the WM updating process. The presence of language knowledge in Chinese characters may enhance the brain's ability to perform verbal WM tasks more efficiently. In contrast, the absence of language information in pseudo-characters adversely affects the continuous updating process of verbal WM.