amnesia, loss of that occurs most often as a result of damage to the from trauma, , neurological or nutritional deficiencies (e.g., deficiency), or toxicity, or infection.Amnesia can be classified in different ways. The most common distinction is between amnesia, in which events following the causative trauma or are forgotten, and amnesia, in which events preceding the causative event are forgotten. In rare instances, an individual may experience both anterograde and retrograde amnesia at the same time.In addition, amnesia may be transient, progressive, or permanent. For example, in transient global amnesia, memory loss is complete but temporary, lasting up to 24 hours, after which memory is gradually regained. Memory loss in degenerative brain diseases, on the other hand, tends to be progressive. Complete and permanent memory loss can result from excessive alcohol or drug intake that produces a so-called blackout state, during which the brain is unable to record new memories, leaving the individual with no memory of events for the blackout period. Childhood amnesia (or infantile amnesia) is the inability of an adult to recollect events from early childhood. This form of amnesia is generally attributed to brain development and the inability to consolidate memories in early childhood. Childhood amnesia may or may not be permanent., Amnesia refers to the loss of memories, including facts, information and experiences. Movies and television tend to depict amnesia as forgetting your identity, but that's not generally the case in real life. Instead, people with amnesia — also called amnestic syndrome — usually know who they are., Amnesia is a deficit in memory caused by brain damage or brain diseases, [1] but it can also be temporarily caused by the use of various sedative and hypnotic drugs. The memory can be either wholly or partially lost due to the extent of damage that is caused..