1. Occurrence. .................................................................................. 14   1. 2004 National Athletic Trainers’ Association   1.  2. Two Forces. ................................................................................. 14   3. Subconcussive Hits. ..................................................................... 15   4. Pathological Changes. .................................................................. 16   45.  The word concussion derives from the Latin concutere for “to shake  violently.” Concussions are just that – a shaking of the brain inside the skull that  changes the alertness of the injured person. That change can be relatively mild (“She  was slightly dazed.”) or profound (“She was unconscious.”). Both situations fall  within the definition of concussion. Concussions are often classified as a form of mild  traumatic brain injury.   5. Metabolic Changes. ..................................................................... 17   6. Symptoms. ................................................................................... 18   7. Why Water Polo Players – Particularly Youth   8. Players – Are Vulnerable. ............................................................ 18  On the Sidelines. .......................................................................... 20   9. B.  Consensus Best Practices for the Treatment of  Concussion for the Period 2002-Present ................................................ 21  Vienna Protocol. .......................................................................... 21   A.  A Primer on Concussions  Introduction.   A.  A Primer on Concussions ....................................................................... 13  Introduction. ................................................................................. 13   Behalf of the Class) .......................................................................................... 71  COUNT III MEDICAL MONITORING (On Behalf of the Class) ........................... 73  COUNT IV  GROSS NEGLIGENCE (On Behalf of Minor H.C.) ............................ 75  VI.  CLAIMS ALLEGED ....................................................................................... 69  COUNT I NEGLIGENCE (On Behalf of the Class) .................................................. 69 