 Oxidative DNA damage is substantially increased in the hippocampus of elderly patients with chronic schizophrenia.Transient global amnesia is a dramatic, sudden, temporary, near-total loss of short-term memory.Various causes have been hypothesized including ischemia, epilepsy, migraine and disturbance of cerebral venous blood flow, leading to ischemia of structures such as the hippocampus that are involved in memory.