The role of explicit contextual truth in counterfactual reasoning: ERP evidence from Chinese.

Previous research has yielded mixed findings on whether counterfactual validity is processed independently of context. We report two event-related potential (ERP) studies examining how contextual information affects counterfactual reasoning in Chinese. In Experiment 1, participants read counterfactual sentences preceded by an explicitly true or false context sentence. Following a true context (e.g., New technology has led to an improvement in building quality), invalid counterfactual words (e.g., increased in "the number of casualties would have increased") elicited a larger P600 than valid words (e.g., dropped). No such effect was found following a false context. In Experiment 2, the true context was compared with a neutral context that was true but irrelevant to the counterfactual evaluation. A P600 effect emerged for the true explicit context but not for the neutral context. We interpret these effects within the retrieval-integration account of language comprehension: when the premise is true and explicitly stated, the relevant information is already activated in the discourse representation, and integrating invalid words with premise-based expectations produces processing difficulty reflected in the P600. These findings demonstrate that online counterfactual reasoning in Chinese is modulated by both the truth and the explicitness of contextual information. Furthermore, participants with higher Theory of Mind/empathy scores showed larger P600 effects in true contexts, but no such correlation was found in false or neutral contexts, suggesting that mentalizing ability plays a role in contextual counterfactual reasoning.