Amnesia, is a condition where mrmory is disturbed. Amnesia affects both organic and functional causes. An example of an organic cause of amnesia is damage to the brain, through trauma or disease. Where as an example of a functional cause involve physcholigical elements such as the defense mechanisms. There is several different types of amnesia which I have broken down below: Lacunar amnesia Lacunar amnesia relates directly the loss of memory on one specific event. Global amnesia Global amnesia is when you lose your entire memory. It is thought that this is a defense mechanism that are body instates after a very traumatic event. As a result of this complete loss, it is common that post-traumatic stress disorder can develop, and involve the spontaneous and realistic flashes of these traumatic memoreis. Traumatic amnesia Traumatic amnesia occurs most often due to a head injury, such as falling or being hit on the head. General with traumatic amnesia the length of the amnesia is directly related to the extent of the injury itself. In often cases a mild trauma is suffered, during events such as a car accident, where the occupant of the car might have an interuption in their memory just before the accident because of a brief loss in the memory transfer mechanism. Dissociative amnesia Dissociative amnesia refers to the long-term repressed memory that can result in emotional or pschological trauma. Childhood amnesia Childhood amnesia, which in several instances is called Infantile amnesia, is probably the most common type of amnesia - the failure to remember events from our childhoods. There is many popular theories as to why we have this loss of memory from our child; most recently it has been thought to be as a result of language development or under-developed parts of the brain.