SLC6A3 and Anxiety: Patients were evaluated at week 16 post TBI, with low cognitive functioning (Rancho Los Amigos ≤ IV) and moderately severe disability (Disability Rating Scale ≥7). Heterogeneous disruption of the nigrostriatal system was documented, and it was observed that the administration of methylphenidate is associated with a decrease in DAT density, which is important for a positive clinical response.No data are presented regarding the mood or anxiety in the patients.