Analysis of Task Demand Effects on Visual and Auditory Mismatch Negativity (MMN) Across Autistic and Schizotypal Traits.

Mismatch negativity (MMN) is an event-related potential component elicited by violations of sensory predictions and is widely interpreted, within the predictive processing framework, as a neural correlate of prediction error. Disruptions in prediction error signalling have been proposed as a potential mechanism underlying the diverse cognitive and perceptual profiles observed in autism and schizophrenia spectrum conditions. In this study, 122 community participants completed auditory and visual oddball tasks with two levels of target detection difficulty while undergoing EEG recording, alongside self-report measures of autistic and schizotypal traits. We found that increased task difficulty significantly reduced MMN amplitude in both modalities, with large effect sizes for auditory (d = 1.826) and visual (d = 1.005) MMN, indicating a modulation by perceptual load. Although associations between MMN amplitude and trait dimensions were limited, emerging patterns suggest a potential dissociation between social and nonsocial autistic traits. These findings address key gaps in the literature, particularly the underrepresentation of visual MMN, and highlight the importance of multidimensional, cross-modal approaches to investigate prediction error mechanisms in neurodiverse populations.