What is Concussion?
[[File:Concussion mechanics.svg|thumb|The arrows show the main forces in a concussion]] [[File:Trauma subdural arrows.jpg|thumb|[[CT scan]], the arrows show places where bleeding occurred.]] [[Image:Gatica1.png|thumb|Rotational force is key in concussion. Punches in [[boxing]] deliver more rotational force to the head than impacts in sports such as [[American football]];boxing carries a higher risk of concussion than football.<ref name=Pellman>{{Cite journal |author=Pellman EJ, Viano DC |title=Concussion in professional football: Summary of the research conducted by the National Football League's Committee on Mild Traumatic Brain Injury |journal=Neurosurgical Focus |volume=21 |issue=4 |pages=E12 |year=2006 |doi=10.3171/foc.2006.21.4.13 |pmid=17112190 |url=http://www.aans.org/education/journal/neurosurgical/Oct06/21-4-12-1028.pdf |access-date=2013-06-16 |archive-date=2008-02-28 |archive-url=https://web.archive.org/web/20080228143922/http://www.aans.org/education/journal/neurosurgical/Oct06/21-4-12-1028.pdf |url-status=dead }}</ref>]] '''Concussion''' is an [[injury]] to the [[brain]] caused by being hit on the [[head]], as often happens in [[Traffic collision|motor vehicle collisions]], fights or contact [[Sport|sports]] such as [[football]]. It is the most common form of [[traumatic brain injury]]. Related terms include '''mild brain injury''', '''mild traumatic brain injury (MTBI)''', '''mild head injury (MHI)''', and '''minor head trauma'''. Patients with severe concussion are occasionally monitored in hospital. The main reason for this is the risk of [[bleeding]] in the [[brain]], which can be life-threatening. Common symptoms of concussion include: [[headache]], dizziness, [[fatigue]], problems with vision, confusion and loss of [[consciousness]]. A person with a mild concussion may have nothing more than a headache or [[Mental confusion|confusion]] for a while. In more severe cases, symptoms tend to last longer, and may include loss of consciousness. Other associated symptoms are: worsening headache, ina