Shedding light on athletes' ability to work through pain, researchers at the University of Luxembourg conducted an experiment in which they conditioned subjects to numb-out their pain sensations.
"We have shown that just as the physiological reaction of saliva secretion was provoked in Pavlov's dogs by the ringing of a bell, an analogous effect occurs regarding the ability to mask pain in humains," says Professor of Biological Physiology at UL Fernand Anton.
In Luxembourg, researchers delivered painful electric pulses to a subject's foot and measured the intensity. Participants were then asked to place their hand in a bucket of ice cold water, which is well known to inhibit pain receptors, during which researchers sounded a bell.
Repetitions indicated that pain was eventually inhibited upon hearing the ringing rather than the sensation of the cold water.
Researchers observed reduced facial reactions telltale to pain reception and reduced muscle reactivity in the 32 participants.
"Conversely, similar learning effects may be involved in the enhancement and maintenance of pain in some patients," says lead author Raymonde Scheuren.
The findings support a 2013 study of triathletes, well-known for their high tolerance for pain and their ability to embrace it, honing a "no pain, no gain" culture.
Researchers compared a test group of 19 triathletes and a control group of 17 non-athletes in their reactions to pain. While both groups identified pain equally, the triathletes were more able to withstand it and less reactive to it, leading researchers to conclude that their training had given them a secondary benefit.
"It is very difficult to separate physiology and psychology," says Prof. Defrin. "But in general, experience is the sum of these factors." The study was published in the journal PAIN.
Another study, conducted in 2012, showed that pain sensitivity was decreased after running by means of fMRI scans.
Pavlov never imagined his study would lead to an explanation of how to push through the pain, although it's likely that his dog pushed through some serious hunger pangs in the last round of tests until the bell's reactivity wore off.
Mind over matter, Fido.
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