Traumatic brain injury (TBI) is a common occurrence in the United States, with an estimated incidence exceeding 1 million injuries per year. Cognitive, emotional, behavioral, and physical impairments are common sequelae of TBI and may, in a significant minority of patients, persist well into the late period following injury. The etiology of these symptoms in individuals with mild TBI is controversial, with hypotheses of postconcussive symptom formation variously ascribing greater or lesser weight to neural damage, pre- and/or post-injury psychological or psychiatric factors, somatization, malingering, or some combination of these. Some of these hypotheses reflect biases common to medicolegal or compensation-related contexts, whereas others are derived from recent neuroimaging and electrophysiology studies. Studies of the latter sort suggest that many of the typical postconcussive symptoms are associated with neurobiological dysfunction in one or more areas of the central nervous system. Whether these symptoms constitute a postconcussive syndrome per se is debatable. Instead, it may be more accurate to describe them as commonly co-occurring symptoms rather than as a syndromal sequela of TBI. The present review addresses these issues including the epidemiology and course of recovery from mild TBI and the validity of the postconcussive syndrome. Suggestions regarding the assessment and treatment of individuals with post-concussive symptoms are offered.
Keywords: diagnosis; electroencephalography; neuroimaging; postconcussive syndrome; traumatic brain injury; treatment.