Corpus callosum microstructural organization mediates the effects of physical neglect on social cognition in schizophrenia.

Exposure to early life adversity is associated with both increased risk of developing schizophrenia and poorer performance on measures of social cognitive functioning. In this study, we examined whether interleukin-6 (IL-6) and Corpus Callosum (CC) microstructure mediated the association between childhood physical neglect and social cognition. Fifty-eight patients with a diagnosis of schizophrenia were included. The CANTAB emotion recognition task (unbiased hit rate) was used to assess social cognition. We found that the microstructural organization of the CC significantly mediated the association between physical neglect and emotion recognition. Furthermore, in a sequential mediation analysis that also considered the role of inflammatory response, the association between physical neglect, and lower emotion recognition performance was sequentially mediated by higher IL-6 and lower fractional anisotropy of the CC. This mediating effect of IL-6 was only present when simultaneously considering the effects of CC microstructural organization and remained significant while controlling for the effects of sex, BMI and medication dosage (but not age). Overall, the findings suggest that the association between physical neglect and poorer emotion recognition in schizophrenia occurs, at least in part, via its association with white matter microstructure.