In simple terms, concussion is a disturbance of brain functioning caused by direct or indirect force to the head. You do NOT have to lose consciousness to suffer a concussion, and it can commonly occur outside of sport. The brain can move within the skull, and if a sudden blow or movement occurs, the brain can knock against the skull, causing swelling and sometimes bleeding.  The brain is a highly sensitive structure and even a small insult can cause a variety of neurological symptoms. Concussion generally occurs from a mild blow to the head, either with or without loss of