문해 능력 상․하위 집단 간 단어 빈도에 따른 사건관련 뇌전위 N400 차이

Differences in Event-Related Potential N400 Responses to Word Frequency Between High and Low Literacy Groups

This study examined literacy-related differences in semantic processing of word frequency using the N400 event-related potential (ERP) component. Participants were divided into high and low literacy groups and performed a lexical decision task with visually presented high- and low-frequency words. ERP data were recorded during task performance. No significant group differences were found in early ERP components (N1 and P200), but distinct patterns emerged in the N400. The low literacy group showed a larger N400 amplitude for low-frequency words than for high-frequency words, indicating a strong frequency effect. In contrast, the high literacy group showed no significant N400 difference across word frequencies. These results support the lexical quality hypothesis, suggesting that high literacy individuals access word meanings more automatically and are less affected by frequency. The findings provide empirical evidence for differences in lexical processing strategies based on literacy. Future research should consider additional variables influencing lexical quality to better understand the neurocognitive mechanisms of word processing.