ABSTRACT
Mild traumatic brain injury (mTBI) or concussion, the most common form of brain injury, results in a complex cascade of injurious and reparative events in the brain, and is not always as mild in nature as the mTBI term would imply. Over the last decades it has become clear that repeated mTBIs may give rise to chronic and sometimes progressive brain changes that may lead to a broad range of psychiatric and neurological symptoms. Presently, there is a convention to categorize TBI into three groups: mild, moderate, and severe, based on initial presentation. At the more severe end of the injury spectrum, the correlation between initial injury severity rating and various outcome measures is relatively robust. At the milder end of the spectrum, this correlation is less tight, and over the last 100 years this has generated confusion with regards to the typical presentation and outcome of milder injuries. For a successful translation of basic science knowledge to the clinic to occur, further techniques and models are needed that better reflect mTBI in humans. The purpose of this chapter is to overview the underlying evidence for the necessity of animal models for mTBI in sports and other high risk activities such as military service.
