Sex differences in cortical thickness in first-time DWI offenders : A preliminary MRI study

Abstract

Driving while impaired by alcohol (DWI) is a persistent yet preventable public health problem. Recent evidence indicates an increasing number of females engaging in DWI behaviour and distinct sex-based trajectories, though sex-based analysis is infrequent in DWI research, especially with respect to the role of cognitive processes. The current study investigated associations between sex, cortical thickness analysis using high resolution Magnetic Resonance Imaging (MRI) and psychological functioning in DWI offenders. It was hypothesized that male offenders possess brain features consistent with impaired executive control, while female offenders show more signs of alcohol misuse and psychological dysfunction. 31 male and 16 female DWI offenders, and 31 male and 31 female non-DWI drivers were recruited. All subjects underwent T1 high resolution MRI scanning and cortical thickness analysis using the CIVET pipeline and assessment on sociodemographic, alcohol misuse, impulsivity, and psychological adjustment. Male DWI offenders, compared to male non-DWI comparators, showed reduced cortical thickness in the posterior and ventral anterior cingulate cortex, the parahippocampal gyrus and anterior insula, areas associated with decision making, error monitoring and emotional processing. Female DWI offenders, compared to their female non-DWI comparators, showed no signs of structural anomalies, but stronger signs of alcohol misuse and depression and anxiety-related dysfunction. These preliminary results suggest that sexual dimorphism contributes to the heterogeneity of the DWI offender population, the trajectory to DWI behaviour, and the uncertain effectiveness of generalized approaches to prevention.