Distant mild traumatic brain injury: a review of electrophysiological and imaging findings at late times after concussion

Mild traumatic brain injury (mTBI), also referred to as concussion, is a common yet incompletely understood condition of the central nervous system. While traditionally considered to be limited in scope and self-resolving, recent studies point to a much more insidious nature of the injury that can continue to evolve for months, years or even the remaining lifetime of the victim. I review the available literature, with a focus on electrophysiological and imaging studies with a follow up period of at least 3 months from injury. Where available, I include observations on the behavioral, cognitive and psychological aspects of the victims. I conclude with an exploration of potential biomarker-based and combined biomarker-neuropsychological methods to study the chronic effects of mTBI.