Differences in Early Visual-Form Processing and Later Semantic Access Between Ancient and Modern Chinese Characters and the Effects of Learning: An ERP Study

Chinese characters developed from ancient script forms, including oracle-bone, bronze, and small-seal scripts, into modern forms, including clerical and regular scripts. The clerical transformation marked a key turning point in this development, and this historical sequence provides a framework for examining how diachronic variation within a single writing system relates to cognitive processing. This study examined behavioral and ERP correlates of this evolution and whether short-term form–meaning learning modulated them. An initial pool of 600 images representing 120 candidate Chinese characters spanning five historical stages was rated online in pairs for visual-form and semantic similarity using 7-point scales, yielding 441,273 valid ratings. Within-character visual-form ratings were averaged to derive evolutionary-continuity scores, and the characters were grouped into four continuity levels to balance learned and unlearned materials; 90 characters were then selected for the main experiment. Twenty-eight university students performed a noun/non-noun semantic judgment task in a within-participant 2 (learning status: learned vs. unlearned) × 2 (character type: ancient vs. modern) ERP experiment. Behavioral analyses compared the two categories and all five script stages, whereas ERP analyses focused on ancient–modern differences in the N170 and N400 windows. Modern characters elicited faster and more accurate responses. Learning was associated with improved performance for both types, with larger benefits for ancient characters. Reaction times differed significantly between small-seal and clerical scripts in both learning conditions, consistent with the historical significance of the clerical transformation. The N170 showed an interaction between character type and learning status: learned ancient characters elicited more negative amplitudes than learned modern characters, whereas this difference was absent for unlearned items. This pattern suggests that early visual-form differentiation varied with learning status, consistent with experience-dependent modulation. The N400 showed main effects of character type and learning status, without an interaction; modern and unlearned items elicited more negative amplitudes. These N400 effects may be related to long-term reading experience, lexical-semantic representations, and semantic activation. Overall, the stage-specific behavioral and component-specific ERP patterns are consistent with an interactive, experience-dependent account in which short-term form–meaning learning may support initial access to unfamiliar forms, whereas more stable semantic processing may partly depend on longer-term reading experience.