Processing of classifier-noun agreement by Chinese as a second language learners: Evidence from ERPs

Classifiers are important linguistic elements in Mandarin Chinese that denote units of entities and require congruence with their accompanying nouns, e.g., "yī-zhīCL-niǎo" (one-CL-bird) instead of "*yī-běnCL-niǎo (one-CL-bird)". This study employed event-related potentials (ERPs) to investigate how Chinese as a second language (CSL) learners process classifier-noun agreement structures, focusing on two violation conditions: classifier-noun mismatch (Mismatch) and classifier omission (Missing). Native speakers exhibited a combined N300-N400 pattern effect in the Mismatch condition and a P600 effect in the Missing condition. By contrast, CSL learners revealed a distinct pattern: the Mismatch condition elicited a P300 effect rather than an N400, while the Missing condition elicited a native-like P600 effect. These findings suggest that CSL learners may assign greater processing weight to structural cues relative to classifier-specific lexical-semantic cues during online processing of classifier-noun agreement. This pattern is consistent with the cue-based processing assumptions of the Competition Model, which posits that L2 learners may tend to assign more weight to cues with higher availability and reliability during real-time comprehension.