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Cold War era intelligence services were keenly interested in the possibilities of using LSD for interrogation and mind control, and also for large-scale social engineering. The CIA conducted extensive research on LSD, which was mostly destroyed.[4] Project MKULTRA (also known as MK-ULTRA) was the code name for a CIA mind-control research program begun in the 1950s and continued until the late 1960s. Tests were conducted by the U.S. Army Biomedical Laboratory now known as the U.S. Army Medical Research of Chemical Defense located in the Edgewood Arsenel at Aberdeen Proving Grounds. Volunteers would take LSD and perform a battery of tests to see the effects of the drug on soldiers. There is much published evidence that the project involved not only the use of drugs to manipulate persons, but also the use of electronic signals to alter brain functioning; for details, see the MKULTRA article proper.
The British government also engaged in LSD testing; in 1953 and 1954, scientists working for MI6 dosed servicemen in an effort to find a "truth drug". (In all probability, MI6 was motivated by rumors that the Soviet Union had developed brainwashing drugs.) The test subjects were not informed that they were being given LSD, and had in fact been told that they were participating in a medical project to find a cure for the common cold. One subject, aged 19 at the time, reported seeing "walls melting, cracks appearing in people's faces ... eyes would run down cheeks, Salvador Dalí-type faces ... a flower would turn into a slug". After keeping the trials secret for many years, MI6 agreed in 2006 to pay the former test subjects financial compensation. Like the CIA, MI6 decided that LSD was not a practical drug for brainwashing purposes.[5]