[Amnestic syndrome--research update].

Amnesia characterized by a severe impairment of the memory without a loss of consciousness is one of the 'classical' organic brain syndromes. According to the course, further symptoms and the circumstances of appearance, several subtypes can be differentiated: transient global amnesia, posttraumatic amnesia, Korsakow's psychosis, and psychogenic amnesia. Many disorders may cause amnesia. Guidelines for the differentiation of the underlying disorders and therapeutic strategies are discussed.