Atypical age-related changes in the structure of the mentalizing network in children with refractory focal epilepsy

Refractory focal epilepsy (rFE) is commonly comorbid with impaired social functioning, which significantly reduces quality of life. Previous research has identified a mentalizing network in the brain-composed of the anterior temporal cortex, medial prefrontal cortex (mPFC), posterior temporal sulcus (pSTS), and temporoparietal junction-that is thought to play a critical role in social cognition. In typically-developing (TD) youth, this network undergoes a protracted developmental process with cortical thinning and white matter expansion occurring across adolescence. Because epilepsy is associated with both social dysfunction and irregular neural development, we investigated whether gray and white matter in the mentalizing network differed between youth with rFE (n = 22) and TD youth (n = 41) aged 8-21 years. Older age was associated with reduced cortical thickness in the bilateral mPFC in TD youth, but not in rFE youth. Compared to TD youth, rFE youth had greater white matter density in the right pSTS. Our findings suggest that rFE youth show atypical patterns of cortical thickness and white matter density in regions of the brain that are typically associated with social information processing, potentially as a result of ongoing seizures, comorbid conditions, or other illness-related factors. These results encourage future research to examine whether such variations in neural structure are predictive of specific social deficits in rFE youth.