Purpose of Review <p>Post-traumatic stress disorder (PTSD) and anxiety commonly occur after traumatic brain injury (TBI), and this may be due in part to a unique neurophysiologic mechanism involving the autonomic nervous system (ANS). This paper will review the relationship between TBI induced ANS dysfunction and neuropsychiatric outcomes, commonly used measurements of ANS dysfunction, and the efficacy of ANS focused treatments to alleviate symptoms of PTSD and anxiety.</p> Recent Findings <p>TBI induced elevations in sympathetic activity can be measured through heart rate variability and may contribute to anxiety disorders, including PTSD. Biofeedback, sleep restoration, and yoga have been found to reduce sympathetic activity and effectively treat PTSD and anxiety in individuals with TBI. There is minimal current research supporting the use of vagal nerve stimulation.</p> Summary <p>Managing post-TBI PTSD and anxiety by actively decreasing sympathetic output is a promising treatment modality. </p>