As with any physical activity, concussion is a real possibility while practicing Martial Arts. Thus, it's important that students take precautionary measures to reduce the risk of a concussion.
A concussion is an injury to the brain caused by any blunt force trauma to the head. It can be caused by a blow to the head or falling and hitting your head on the ground. Within the skull, there is space for the brain to move in and try to soften any impacts that might normally occur from simple everyday activities. In a concussion, the brain is so violently moved it actually collides with the skull and can cause anywhere from bruising and swelling to bleeding.
To help prevent a concussion, students should always wear the appropriate gear, especially a helmet when sparring. The floor should have some matting or softer area to fall upon. Make sure the area is clear from clutter or any spills that might cause slippage. In addition, before sparring or entering actual combat, students should learn and practice a bit how to fall to prevent a concussion or other severe injuries. Always have others around, especially someone who might be qualified, to ensure they can respond if something were to happen. And most importantly, whatever training is done should be conducted with a level of control. If you don't know how to control your hits, you probably shouldn't be out on the floor.
Even with all the safeguards in place, a concussion can and does still happen. Thus, it's important to both recognize the signs of and how to respond to a concussion.
Concussions can vary greatly from mild to severe. In a mild concussion, the student might only exhibit slight dizziness or a headache. More severe concussions can result additionally in nausea, blurred vision, short-term memory loss, and loss of consciousness. Other things to look for is if the disorientation or confusion persists, the student is unable to walk, or continually says the same thing over and over again.
Because the injury is a trauma to the brain, the student might seem to at first recover but then suffer from the effects of the concussion later on. Thus, it is important that regardless of the severity, the student be checked out by a doctor or medical professional. If the concussion is severe, such as a loss of consciousness, the student should not be moved immediately for fear of causing other injuries to the spine.
Concussions are not a joke and can lead to long term issues, including death. Don't try to be the "macho" man (or woman) and simply ignore the effects.