<prompt> Wernicke;s encephalopathy is due to deficiency ofThiamineNiacinFolic acidPyridoxine  <response>: The commonest cause of the organic amnestic syndrome is chronic alcohol dependence. It is also called as Wernicke-korasakoff syndrome. Wernicke;s encephalopathy is the acute phase of delirium proceeding to the organic amnestic syndrome, while korasakoff;s syndrome is the chronic phase of the amnestic syndrome. Ref: a sho textbook of psychiatry, Niraj Ahuja,7th edition, pg no. 27 