Amnesia.

Glossary Alcoholic blackout Amnesia without loss of consciousness, in which the intoxicated person retains the ability to perform certain ‘automatized’ behaviors, without any subsequent memory for the episode. Amnesia A special case of forgetting in which the memory loss is greater than would be expected under ordinary circumstances. Anterograde amnesia affects memory for events occurring after the instigating event; retrograde amnesia affects memory for events occurring before the instigating event. Amnesic syndrome A profound deficit in learning and memory usually associated with bilateral damage to the diencephalon or the medial portions of the temporal lobe. It always involves an anterograde amnesia, and may involve a retrograde amnesia as well. Functional amnesia A significant loss of memory attributable to an instigating event, usually stressful, that does not result in insult, injury, or disease affecting brain tissue. Its most common forms are psychogenic amnesia, psychogenic fugue, and multiple personality disorder. Implicit memory In contrast to explicit memory, which entails conscious recall or recognition of past events, implicit memory refers to any effect of a past experience on subsequent experience, thought, or action – for example, priming effects. Infantile and childhood amnesia An amnesia observed in adults, affecting memory for personal experiences occurring in the first 5–7 years of life. Infantile amnesia commonly covers the period before language and speech develop. Posthypnotic amnesia A retrograde amnesia induced by means of hypnotic suggestion; it may be canceled by a prearranged reversibility cue. Priming A phenomenon where an event facilitates (positive priming) or impairs (negative priming) performance on another, later task. Source amnesia A phenomenon where a subject retains access to new information acquired during a learning experience, but forgets the learning experience itself; it is commonly reflected in cryptomnesia, or unconscious plagiarism. Transient global amnesia A benign and temporary amnesia characterized by sudden onset, apparently caused by momentary vascular insufficiencies affecting brain tissue. Trauma-memory argument The notion, rooted in the nineteenth century ideas of Sigmund Freud and Pierre Janet, that psychological trauma causes amnesia by virtue of a process of repression or dissociation. Traumatic retrograde amnesia A retrograde amnesia resulting from a concussive blow to the head; most of the affected memories are eventually recovered, except for a ‘final RA’ affecting the accident itself.