Brainwashing refers to an extreme form of indoctrination of individuals, or the reindoctrination of ideological deviants. It may involve police torture techniques to weaken resistance, including the the denial of sleep and food or use of drugs to create confusion and a blank, receptive mind for propaganda. In the case of political prisoners, brainwashing may be the preparation for a show trial where the victim confesses guilt, thus creating propaganda for use at home and abroad. In the case of prisoners of war, they may become collaborators during the war or be repatriated afterwards with subversive intent. Foreign espionage agents may be brainwashed to act as double agents.
Brainwashing evolved in the East and recent practices are largely confined to countries such as North Korea, China and the USSR, where its objective was to form or reform good communists.