This document is a fax from [redacted], [redacted] Legal Group, DCI Counterterrorist Center, CIA to Steve Bradbury, Office of Legal Counsel, Department of Justice, containing answers composed by the CIA' s Office of Medical Services to the questions that Bradbury faxed to [redacted] yesterday regarding interrogation techniques, specifically the effect that sleep deprivation can have on lowering the threshold of pain that detainees feel when enduring other interrogation techniques.