|MadSci Network: Neuroscience|
Dear Mr. Peterson, The answer to your question is quite simple: there is no such thing as truth serum. Now the elaboration: what is commonly known as "truth serum" is actually a ultra-short-acting barbiturate called sodium amytal. This drug can induce a "twilight" state between waking and unconsciousness, in which it was once thought that people would be more suggestible and less able to resist questioning. In fact, it doesn't work very well. It's basically the same idea as getting your friend drunk to get him or her to tell you things he or she ordinarily wouldn't say. Needless to say, this is a far cry from a "truth serum." It has been used in combination with hypnosis, another method of very dubious effectiveness. In fact, there is now a lot of evidence that some people can be made to "remember" things that never happened with hypnosis. Sodium amytal was tested by the CIA (along with many other drugs) in the 1950s and 1960s, but I think it is safe to say that it is not used much for the purpose of eliciting information anymore, at least not by legitimate organizations. Like the polygraph or "lie detector," another marginally effective investigative tool that has been made far too much of in fiction, truth serum is really not a particularly useful way to get to the bottom of a suspect's story, so law enforcement uses more ordinary means, such as "good cop, bad cop," bluffing (i.e. telling the suspect that you know more than you really do), negotiating, etc. to try to convince a suspect to cough up the truth.
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