Proceedings of the Annual Meeting of the Cognitive Science Society

Individual differences in executive control, including working memory capacity (WMC), are known to modulate sentence processing, but their role in neurodivergent populations remains unclear. This study examined how WMC relates to the processing of subject- and object-relative clauses in Brazilian Portuguese speakers with and without ADHD, using a WMC task and a self-paced reading paradigm with comprehension questions. Online measures showed that WMC modulated reading times differently across groups at the onset of the relative clause in object-extracted structures. This pattern suggests that both expectation-based and memory-based factors contribute to processing difficulty, consistent with locality accounts. Offline measures showed that accuracy was reduced in the OR condition and modulated differently by WMC across groups, with WMC predicting higher accuracy in the control group but not in the ADHD group. These findings suggest that reading times may reflect different processing strategies across cognitive profiles.