[Transient global amnesia. Case report]

All memory disturbances, especially those developing suddenly, cause anxiety of the patient. Transient global amnesia is a form of amnesia of interest in many aspects. The amnesia was described in 1964 by Fisher and Adams, and as yet about 1000 cases have been reported. Middle aged or elderly patients prevail. The attack of amnesia lasts from several to about 20 hours and begins suddenly being regarded as mental confusion. The amnesia covers recent and remote events in many years. During the attack the patient is not appearing to be ill, but is depressed not knowing what has happened. The awareness of own personality, the ability to solve logical problems and visuospatial functions are preserved. The ability to execute complex activities, e.g. car driving, is normal. The aetiology of the disorder is completely unknown. The hypotheses for explaining the syndrome are: 1. ischaemia in the posterior cerebral arteries region with transient fall of blood supply through the vertebrobasilar system, 2. epilepsy or migraine, 3. disturbed aggregation of platelets in the cerebral vessels leading to loss of vessel patency. The first hypothesis seems least plausible. Attacks of this amnesia were noted after triazolam, after thalamic infarction and cerebral angiography, in brain tumours, hydrocephalus, scleroderma, frontal lobe haemorrhage. After an attack the events occurring in it are not remembered. Recurrence of attacks is very rare. Most authors consider that the disorder is benign and regresses without sequelae or only with slight changes in cognitive functions and memory fixation.