Successfully used by some major intelligence powers, mainly in the Soviet Union and the USA, as a torture and interrogation method. The subject is submerged in a sensory deprivation tank while unconscious, thus waking up sensory deprived. The effects of this are claustrophobia and delusions, since the subject believes he/she is buried alive. Usually, total nervous breakdown is achieved within 72 hours, making any attempts by the subject to resist interrogation futile and facilitating subsequent brain-washing. Side effects include cardiac complications and insanity.