Patients with concussion exhibit a brief disturbance in consciousness due to injury, which does not last more than half an hour. They also experience recent memory loss, meaning patients cannot recall the circumstances of the injury. Additionally, some patients may experience a range of clinical symptoms including headache, dizziness, nausea, insomnia, loss of appetite, lack of concentration, and decreased memory. The vast majority of concussion patients can recover with one to two weeks of rest. Furthermore, head CT scans of concussion patients do not show any organic changes. Therefore, concussions are generally not considered minor injuries.