Mild traumatic brain injury: The elusive timing of “recovery”

raumatic brain injury (TBI) is typically described by its severity anging from mild to severe. Mild TBI (mTBI) is by far the most ommon, constituting ∼80–90% of all TBIs [5]. While there is little isagreement over definition and classification of moderate-toevere TBI, classification of mTBI has a lengthy history of ardent ebate, especially over whether any neurocognitive or neuroehavioral sequelae may exist beyond the acute phase [14,30]. or example, concussion, a term used since antiquity, most often mplies a transient neurologic condition without lasting sequelae 13]. However, concussion is a mTBI, likely defining the least severe TBI [37]. As such, the terms concussion and mTBI often are used nterchangeably and will be in this commentary. Indisputably, conussion occurs because of acute brain injury; the debate is how to easure the pathophysiological effects of the injury and whether uch injuries have any lasting effect? In sports concussion how o determine return to play is assumed to be based on outward hysical and behavioral measures implicating the return of noral brain function. Fortunately, the majority of those who sustain mTBI experience a positive outcome without detectable sequelae, eturning to normal activities including competitive sports without