Korsakow's psychosis was first described in 1887. This is characterized by a loss of memory, and falsification, with a marked tendency to disorientation, and is often due to chronic alcoholism. It is practically always accompanied by polyneuritic symptoms. According to Bonhöffer, it usually follows delirium tremens. This occurred in one-fourth of Kraepelin's cases. Occasionally it begins suddenly, but as a rule gradually, during the course of a chronic alcoholism. The patients frequently complain of dizziness, headaches and fainting spells. In the foreground of this affection is the impairment of memory. This is one of the characteristic features. The events of a few hours ago are completely forgotten. Disorientation appears next. This affects time more than anything else. The power of apprehension or perception is very markedly impaired (one-sixth of the normal in Kraepelin's cases) and the reaction time is greatly increased. He also found memory reduced to one-third or one-fourth of the normal on actual tests (repetition of words and syllables). Falsification of past events is also demonstrable. This often leads to elaborate delusion formations. The mood is usually anxious at first, later indifferent, dull, suspicious, irritable, in some eases cheerful and even humorous. The methods of life are completely changed. The patients neglect themselves, lie in bed, etc. The physical signs are those of neuritis. Muscular pains in the limbs appear, with evidences of loss of power. Paraplegias and weakness of the grip are found. Romberg's sign is frequently present. Anesthesias, hyperesthesias or paresthesias are noted. The reflexes are usually decreased, rarely increased. Ataxia and other difficulties of gait are common. The pulse is usually slower as a result of involvement of the vagus. Speech difficulty, writing defects, facial paralyses, weakness of the eye muscles, with inequality and inactivity of the pupils, are to be expected. There are usually tremors of the fingers. Epileptiform convulsions are not infrequent. Aphasia, agraphia, apraxia, monoplegia, hemiplegic, etc., are observed in many cases. Physical disturbances of various kinds due to chronic alcoholism are also present.