FRONTOSTRIATAL WHITE MATTER INTEGRITY RELATIONS WITH 'COOL' AND 'HOT' SELF-REGULATION FOLLOWING PEDIATRIC TRAUMATIC BRAIN INJURY.

Traumatic brain injury (TBI) produces microstructural damage to white matter pathways connecting neural structures in prefrontal and striatal regions involved in self-regulation (SR). Dorsal and ventral frontostriatal pathways have been linked to cognitive ('cool') and emotional ('hot') SR, respectively. We evaluated the relation of frontostriatal pathway fractional anisotropy (FA) 2 months post-TBI on cool and hot SR assessed 7 months post-TBI. Participants were ages 8-15, including children with uncomplicated mild TBI (mTBI; n=24), more severe TBI (cmsTBI; n=60), and typically developing children (TD; n=55). Diffusion tensor tractography was used to map frontostriatal pathways. Cool SR included focused and sustained attention performance, and parent-reported attention while hot SR included risk-taking performance and parent-reported emotional control. Multivariate general linear models showed that children with cmsTBI had greater parent-reported cool and hot SR difficulties and lower dorsal and ventral FA than TD children. Focused attention, risk taking, and emotional control correlated with FA of specific dorsal and ventral pathways; however, only the effect of TBI on focused attention was mediated by integrity of dorsal pathways. Results suggest frontostriatal FA may serve as a biomarker of risk for SR difficulties or to assess response to interventions targeting SR in pediatric TBI and in broader neurodevelopmental populations.