What is a concussion?

Medical literature consistently defines a "concussion" as a traumatically induced disruption of brain function.  One common misconception is that the disruption of brain function must include a loss of consciousness.  In truth, a loss of consciousness is not a necessary requirement for the diagnosis of a concussion.  While the disruption of brain function certainly can include a loss of consciousness, medically accepted definitions of "concussion" also include a loss of memory for events immediately before or after the injury, and any alteration in mental state at the time of injury (such as feeling dazed, disoriented, or confused).