From a press release
“Scientists have known for many years that on-going pain in one part of the body is reduced when a new pain is inflicted to another part of the body. This pain blocking is a physiological reaction by the nervous system to help the body deal with a potentially more relevant novel threat. To explore this “pain inhibits pain” phenomenon, painful electric pulses were first administered to a subject’s foot (first pain) and the resulting pain intensity was then measured. Then the subject was asked to put their hand in a bucket of ice water (novel stimulus causing pain reduction), and as they did so, a telephone ringtone sounded in headphones. After this procedure had been repeated several times, it was observed that the pain felt from the electrical stimulation was reduced simply when the ring tone sounded.”
Raymonde Scheuren, Fernand Anton, Nathalie Erpelding, Gilles Michaux. Beep Tones Attenuate Pain following Pavlovian Conditioning of an Endogenous Pain Control Mechanism. PLoS ONE, 2014; 9 (2): e88710 DOI: 10.1371/journal.pone.0088710
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