A concussion generally occurs when there is a mild injury to the brain without major rupture of blood vessels or physical visible damage to the brain tissue. How bad is a concussion, is sometimes difficult to determine in the very initial stages. It is important to give sufficient rest to the brain and avoid bright light Which can otherwise act as an irritant to the brain and thereby delay or affect recovery. When a person has a concussion, he or she may feel dizzy, nauseous and unwilling to participate in day-to-day activities. There may be some degree of short-term memory loss, difficulty in memory recall along with other signs such as wanting to sleep longer and have tendency to become lethargic.