It´s not the purpose of this type of interrogation.
There are many extreme methods of interrogation that are still, sadly, in use today, particularly in military environments. A dilemma of extreme interrogation is that whilst they may produce information, the truth of these may be a different matter. When subjects reach satisficing, they will say or do anything to reduce their discomfort. Professional interrogators knows that! And unreliable information may be verified as credible at a later date.
Extreme Interrogation.
Threats vary on a long sliding scale from minor to extreme. You can threaten to tell other people or you can put a gun in a person's mouth and threaten to pull the trigger. At the extreme, the goal is to create terror and belief that pain or something highly undesirable is about to happen. Threats may be of physical pain, harm to significant others or action that the subject desperately seeks not to happen. Blackmail works in this way, where the threat of exposure of secrets can lead people into desperate action. Threats work on fear and anticipated pain, where the thought and expectation of discomfort leads the person to imagine and virtually feel the pain, physical or emotional, that would be experienced. Threats may be unspoken, for example where the interrogator plays with a weapon or where instruments of torture are visible. If the individual is immune to threats, then people they hold dear may be threatened, such as friends. The problem with threats is that if the subject calls your bluff and you do not carry out the threat, then your credibility as an interrogator is lost.
The application of pain is a basic technique of extreme interrogation, whether through creating general discomfort, physical beating or using instruments of torture. Whilst many people will do anything to escape pain, extreme cases such as SF/SOF is trained to withstand high levels of pain. It also has surprised many interrogators how people with high ideals will go through terrible pain rather than give in.
Interrogators can also use disorientation methods to disorient their subjects, including:
Language that causes confusion.
Rapid barrages of questions.
Use of hypnosis and hypnotic language.
Time distortion, such as through changing meal times, turning lights on and off at different times.
Use of narcotics.
The basic principle of disorientation is to reduce the person's sense of judgment and their ability to make rational decisions. When asked questions, they may thus give answers that they would not give if they were able to think rationally before responding.
Depriving people of basic needs can lead both to disorientation, causing poor judgment as above, or desperation that leads to provision of information in order get that which is needed.
Deprivation can include:
Food and drink: Extreme hunger or thirst can persuade.
Sleep: Lack of sleep disorientates.
Company: Solitary confinement leads to craving attention (especially for some).
Sensation: Sensory deprivation disorientates.
Access: To information or significant others.
Debilitation is the systematic weakening of the person. Physically this may be through means such as corporal punishment, pain and deprivation. Psychological weakening may take place through humiliation and other actions, such as making them stand naked, forced religious sacrilege, triggering of phobias and mock executions.
Torture has many faces -and they work.