A person having an attack of<unk>  has almost no capacity to establish new memories, but generally appears otherwise mentally alert and lucid, possessing full knowledge of self-identity and identity of close family, and maintaining intact perceptual skills and a wide repertoire of complex learned behavior. The individual simply cannot recall anything that happened outside the last few minutes, while memory for more temporally distant events may or may not be largely intact. The degree of amnesia is profound, and, in the interval during which the individual is aware of his or her condition, is often accompanied by anxiety. The diagnostic criteria for<unk> , as defined for purposes of clinical research, include: * The attack was witnessed by a capable observer and reported as being a definite loss of recent memory (anterograde amnesia). * There was an absence of clouding of consciousness or other cognitive impairment other than amnesia. * There were no focal neurological signs or deficits during or after the attack. * There were no features of epilepsy, or active epilepsy in the past two years, and the patient did not have any recent head injury. * The attack resolved within 24 hours. Progression of a<unk>  event This onset of<unk>  is generally fairly rapid, and its duration varies but generally lasts between 2 and 8 hours. A person experiencing<unk>  typically has memory only of the past few minutes or less, and cannot retain new information beyond that period of time. One of its bizarre features is perseveration, in which the victim of an attack faithfully and methodically repeats statements or questions, complete with profoundly identical intonation and gestures "as if a fragment of a sound track is being repeatedly rerun." This is found in almost all<unk>  attacks and is sometimes considered a defining characteristic of the condition. The individual experiencing<unk>  retains social skills and older significant memories, almost always including knowing his or her own identity and the identity of family members, and the ability to perform various complex learned tasks including driving and other learned behavior; one individual "was able to continue putting together the alternator of his car." Though outwardly appearing to be normal, a person with<unk>  is disoriented in time and space, perhaps knowing neither the year nor where they reside. Although confusion is sometimes reported, others consider this an imprecise observation, but an elevated emotional state (compared to patients experiencing Transient Ischemic Attack, or TIA) is common. In a large survey, 11% of individuals in a<unk>  state were described as exhibiting "emotionalism" and 14% "fear of dying". The attack lessens over a period of hours, with older memories returning first, and the repetitive fugue slowly lengthening so that the victim retains short-term memory for longer periods. While seemingly back to normal within 24 hours, there are subtle effects on memory that can persist longer. In the majority of cases there are no long-term effects other than a complete lack of recall for this period of the attack and an hour or two before its onset. There is emerging evidence for observable impairments in a minority of cases weeks or even years following a<unk>  attack. There is also evidence that the victim is aware that something is not quite right, even though they can't pinpoint it. Persons suffering from the attack may vocalize signs that 'they just lost their memory', or that they believed they had a stroke, although they aren't aware of the other signs that they are displaying. The main sign of this condition is the repetitive actions of something that is not usually repeated.
Transient global amnesia
Childhood amnesia
Excited delirium
Transient epileptic amnesia
Emergence delirium
Drug-induced amnesia
Post-traumatic amnesia
Psychogenic amnesia