A “placebo” is a medical term for a treatment that gives only psychological benefits (or none). If you have a drug trial you might want to give some patients the real drug and others a placebo, then wait to see what happens.
“Placebo” is a Latin word transplanted into English. In Latin in means “I shall be pleasing,, and its root is “placere,, to please. It’s not particularly old, as words go; it only entered usage in medicine in the late 1700s. It was used in liturgies (in Latin) long before that, though.
They probably didn’t do large scale medical research in the 1700s, unless of course you consider the existence of people in the 1700s to be, by itself, large scale medical research. Modern medical research has gotten more sophisticated, and that led to the creation of a new word in the 1990s: “nocebo.” A “nocebo” is the opposite of a “placebo.” It creates a feeling of unhealthiness for no medical reason. It’s not a dosage you’d give to someone in a research study though. Instead it’s a factor that can have a negative effect on a treatment, even though there’s no therapeutic reason for it. A nocebo might be a belief, or an attitude, or even something cultural. As Robert and Michele Root-Bernstein wrote in 1997: “Research has also shown that the nocebo effect can reverse the body’s response to true medical treatment from positive to negative.”
A new field, ripe for study, is of course the interaction of nocebo and placebo effects. If you give a placebo to someone who doesn’t believe it’s going to do any good, and it doesn’t, is that because it’s just a placebo? Or is their belief acting as a nocebo effect, thus canceling out the placebo effect? Even worse, what if a patient is suffering from an ailment because of a nocebo effect, and you give them a placebo — in the inevitable battle of effects, which one will previal? There’s a grant in there somewhere.
