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No. 22: Jul-Aug 1982

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Conditioned responses that short-circuit the conscious brain

Don't let the title of this item deter you; this is serious stuff. We all know about the placebo effect. A sick patient improves because he believes he is getting a helpful medicine, even though it is an inert substance. The reverse works, too, at least in experiments with mice. It seems that mice can be conditioned into believing that an ordinarily delectable substance (saccharin and water) gives them stomach pain, by simultaneously injecting them with a pain-producing chemical. Unexpectedly, this chemical also suppressed the immune system of the mice. The mice, of course, knew nothing about the effect on their immune system. Nevertheless, whenever they received saccharin after being conditioned, their immune system was suppressed even though the pain-producing chemical was not administered. While one can imagine the mice consciously associating saccharin and stomach pain, and their brains somehow sending signals that simulated pain, it seems inconceivable that the mice knew anything about their immune system. We have always assumed that the placebo effect (and its reverse) worked because of the subjects' logical association of cause and effect, but evidently there is something else going on here!

(Wingerson, Lois; "Training the Mind To Heal," Discover, 3:80, May 1982.)

Comment. This all opens a rather large Pandora's Box, because it implies that seemingly innocent signals can trigger unrealized reactions. It's something like a post-hypnotic suggestion. Some cause -- not recognized as a cause -- results in an effect -- not consciously related to the real cause. We could all be puppets, not even recognizing the strings that control us!

From Science Frontiers #22, JUL-AUG 1982. 1982-2000 William R. Corliss