Source:http://linkedlifedata.com/resource/umls/id/C0006107
MSH: A nonspecific term used to describe transient alterations or loss of consciousness following closed head injuries. The duration of UNCONSCIOUSNESS generally lasts a few seconds, but may persist for several hours. Concussions may be classified as mild, intermediate, and severe. Prolonged periods of unconsciousness (often defined as greater than 6 hours in duration) may be referred to as post-traumatic coma (COMA, POST-HEAD INJURY). (From Rowland, Merritt's Textbook of Neurology, 9th ed, p418),NCI: A violent jar or shock, or the condition which results from such an injury.,NCI: A violent jar or shock, or the condition which results from such an injury.,MEDLINEPLUS: <p>A concussion is a type of <a href='http://www.nlm.nih.gov/medlineplus/traumaticbraininjury.html'>brain injury</a>. It is a short loss of normal brain function in response to a <a href='http://www.nlm.nih.gov/medlineplus/headinjuries.html'>head injury</a>. Concussions are a common type of sports injury. You can also suffer from one if you suff