In the United States, the Central Intelligence Agency tested the drug on subjects for different reasons. The name for one of these test projects was MK-ULTRA. Subjects did not know they were given the drug. It was used in interrogations to see if it would make people tell the truth, or remember things they had forgotten. It was also used to convince people they were becoming insane, or that things had happened which really had not, such as an invasion from outer space, or a Communist takeover of the country, or that their bodies were transformed in some way. The CIA supposedly felt it was important to learn how ordinary citizens might react to such things if they happened. The drug sometimes made the scenarios more believable. The effects of these experiments were often harmful to the subjects, even years later, because of the intense anxiety or fear caused when someone unknowingly takes a drug like LSD.