Introduction to the brain imaging and behavior special issue: mild traumatic brain injury among active duty service members and veterans.

Abstract

As noted in the recent special issue in Brain Imaging and Behavior (Tate et al. 2012), there has been a growing interest among researchers, clinicians, policy makers, patients and family members, and other consumers regarding mild traumatic brain injury (mTBI). This interest stems from several converging points of view including epidemiology data that indicates the significant prevalence and incidence of mTBI in the general population, associated legal issues (i.e., symptom validity), our growing understanding of the effects of concussive and subconcussive sports injuries (i.e., chronic traumatic encephalopathy), and an attentiveness to the relationship between TBI and dementia in a rapidly aging society. These interests combined with recent advances in cognitive sciences, improvement in the clinical management of mTBI, a growing number of treatment options, and acquisition and analysis of imaging data are propelling the effort toward identification of unique biomarkers that could improve diagnosis, prognosis, and guide/assess treatments. Not surprisingly, mTBI occurs in the context of a number of different situations. However, in addition to common means of head injury among civilians (i.e., motor vehicle accidents, falls, and other collision-related events), Military and Veteran populations have a number of additional deployment-related risk factors for head injury including combatant training, gunshot wounds, blast exposure, and assault. Brain-related injury in many Military and Veteran TBI patients is also complicated by additional comorbid conditions not typically experienced by civilian TBI patients including combat-related PTSD or depression, burns, hearing dysfunction, traumatic amputations and other injuries associated with combat. With the recent combat operations in support of Operation Enduring Freedom (OEF), Operation Iraqi Freedom (OIF), Operation New Dawn (OND), and other conflicts, surveillance data from the Defense and Veterans Brain Injury Centers (DVBIC) have identified over 327,299 U.S. ServiceMembers and Veterans across the branches of service that sustained a TBI (https://dvbic.dcoe.mil/sites/default/files/DoD-TBI-WorldwideTotals%202000-2015Q1-May15-2015.pdf). These head injuries occur both during theatre operations and in garrison with the majority (>70 %) falling into the mild range of severity. The sheer numbers of Service Members and Veterans injured underscore the importance of advancing our understanding of the functional, clinical, and long-term consequences of mild TBI, especially in Military populations. Moreover, there is a growing interest in understanding the impact of mTBI on unit readiness, return to duty, safety of troop operations, troop retention, and long-term cognitive effects (i.e., chronic traumatic encephalopathy and possible links with dementia). Given these concerns, there has been a sudden and rapid growth in the number of investigators * David F. Tate David.Tate@mimh.edu