The dissociation of grammatical category from multiple levels in the neural representation of words: stress typicality effect among Chinese EFL learners

This study aimed to dissociate grammatical category from multiple levels during the processing of stress typicality, with a focus on understanding how class information is represented among Chinese speakers who learn English as a foreign language (EFL). Disyllabic English words were used as stimuli and three event-related potentials (ERPs) components, including P200, N400, and LPC (late positive component), were analyzed across two tasks that varied in their direct utilization of grammatical cue: lexical decision task in Experiment 1 and grammatical classification task in Experiment 2. Our findings indicate differences between words exhibiting distinct stress and grammatical patterns, suggesting that prosodic and grammatical cues are dissociated early around 200 ms, and continue to influence lexical access into later time windows. Additionally, the direct tapping of grammatical cues appears to impact how classes are processed, as differences between tasks were observed. In summary, our results reveal that grammatical class could be represented at the orthographic level and dissociated from prosody at an early stage. Furthermore, the representation of grammatical class among Chinese EFL learners may be independent of semantics.