Neural correlates of semantic typicality during episodic memory retrieval in autism spectrum disorder

This study examined the effects of item typicality (typical vs. atypical), encoding type (categorical vs. perceptual), and neurodivergence (autistic vs. neurotypical male adults) on memory discrimination and associated neuronal patterns. Despite similar overall memory discrimination performance between groups, analyses of event-related potentials revealed that neurotypicals displayed an early ERP effect, suggesting reliance on familiarity-driven processes. In contrast, autistic participants showed a later ERP modulation, indicating a reliance on recollection-based processes. Notably, relying on either familiarity or recollection influenced the activation in the post-old/new-response period, in which only neurotypical adults needed to reinstate item details for the subsequent Remember-Know-Guess (R-K-G) judgments. These findings suggest that autistic adults may recruit different cognitive processes to achieve memory performance comparable to neurotypical adults. Additionally, our results suggest that item typicality interacts with encoding type in modulating the cognitive processes underlying memory retrieval and their neural correlates in both autistic and neurotypical adults. The study highlights the need to investigate the role of semantic processes in episodic memory retrieval in both neurotypical and autistic individuals.