Truth Out -The CIA, apparently, was not legally authorized to subject detainees to some of the more extreme forms of torture described in the manual, such as immersion in an icy "Water Pit" and forced confinement in a 55-gallon drum or barrel, the purpose of which was to "demonstrate the reaction to uncooperative behavior and accelerate the physical and psychological stresses of captivity."
But other techniques cited in the PREAL instructional manual, such as walling, cramped confinement, facial slap, sleep deprivation, attention grasp, facial hold and stress positions were included in Yoo and Bybee's August 1, 2002 torture memo.
The manual also describes how the use of hooding (a form of sensory deprivation) and sexual humiliation can be used as a form of torture, which military interrogators employed against detainees at Guantanamo. Moreover, SERE trainees were also subjected to isolation, according to the PREAL manual (another form of torture detainees underwent), including a harsh form where the isolated prisoner was hooded and cuffed in what the manual called "Iso-stress."
....The harsh physical techniques included in the manual are consistent with notes written by psychologist Bruce Jessen for a SERE survival-training course more than two decades ago, which said enemies who captured US personnel used methods of torture, such as those outlined in the PREAL manual, as a way of gaining "total control" over the prisoner. The "end goal," according to Jessen's handwritten notes, was to make the prisoner feel "completely dependent" on his captors so they would "comply with [their] wishes."