The Power of Suggestion? (And NO scratching!)

"The two systems are constantly in communication."

"[The] brain is involved in the individual's survival, and the immune system is involved in survival, and that's what they do."

"So of course they talk to each other." 

Jonathan Kipnis, professor of pathology and immunology, Washington University, St.Louis 

 

"[In other words, the findings suggest that] what we think matters."

"It was striking to see the consistency of the effect and the fact that it was displayed across the vast majority of participants."

"What was particularly striking was that directing attention toward the inflamed area changed not only what participants experienced, but the inflammatory response itself."

"This raises the possibility that our subjective experience of what is happening in the body is not only a passive process but may be actively contributing to how physiological responses are regulated."

"I’ve studied humans for more than 20 years, and this was the most striking effect I’ve ever seen."

"Our cognitive processes can shape how the body regulates itself. Feeling pain does contribute to the healing process."

"People are aware of the placebo effect, when someone is given a sham drug, and they think it’s real and they get better."

Liron Rozenkrantz, principal investigator, Azrieli Faculty of Medicine, Ban-Ilan University, Israel  

A view of Bar-Ilan University’s Azrieli Faculty of Medicine. Credit: Courtesy of Bar-Ilan University.

 

Published in the journal Nature Human Behaviour, a study out of Israel suggests that attention to injuries in/on the body may align the brain with the immune system to work together to diminish the effects of inflammation. Inflammation is the most common cause of alerting the immune system to the presence of of injury, infection or an irritant. Ignoring a pain or an itch, according to this new study, may worsen the inflammation in some situations. 

 

Deliberately toughing it out in the hope that it will disappear appears not to be the solution; rather awareness of and mindful attention to the injury appears to prompt brain and immune system to work in tandem toward relief. The study found that when people attempted to distract themselves from an itch, the inflammation -- measured by redness and skin swelling -- grew larger and lasted longer than a focus on it would achieve in alleviating both symptoms.

 

In the scientific world of human biology growing evidence has surfaced that the brain and the immune system, assumed to be separate and distinct from one another, have in fact an intimate relationship. Links have been made between dysfunctional immune activity and inflammation with a number of psychiatric and neurological disorders which include schizophrenia, depression, long COVID and dementia. 

 

Illustrative: A man suffers shoulder pain (BitsAndSplits; iStock via Getty Images)

 

Professor Rozenkrantz, the main author of the study and her colleagues, focused on 57 study participants by deliberately causing inflammation on their forearms, similar to the results seen with "a bad mosquito bite" by pricking their skin with a drop of histamine, a chemical used by immune cells that triggers an inflammatory response. Researchers instructed their subject participants to focus fixedly at a screen, distract themselves with a cognitive task appearing on the screen, or alternately focus attention internally on the sensations felt at the inflamed site (without touching or looking at the site).

 

Directing attention to the inflamed skin sensations, both the swelling and redness diminished. In contrast, when the same study participants distracted themselves, more inflammation with swelling and redness of a 50 percent increase were experienced by 90 percent of the participants. The inflammation recovered faster when paid attention to. When 20 minutes had elapsed, close to 90 percent of those involved who paid attention saw their swelling stabilize or diminish. With the distracted test, 46 percent only, saw improved inflammation.

 

The message seemed clear, that additional input from the brain was likely to have aided the immune system in improved regulation of the inflammatory response. "It was striking to see the consistency of the effect and the fact that it was displayed across the vast majority of participants", explained Dr. Rozenkrantz. While the mechanisms involved are not fully understood, at least two ways exist that the brain regulates inflammation. The inflamed sensations themselves appeared to have a role. Researchers in a followup experiment covered people's skin with lidocaine a local anesthetic, following the administering of Histamine. 

 

The dulled sensations enabled study participants to pay attention to the inflammation with a lesser reward in dulled response forthcoming. A smaller effect on the itch resulted even when paying attention to the inflammation with dulled sensation, in comparison with the experiment absent numbing cream. People experienced greater heart rate variability, a widely used proxy for increased parasympathetic activation when attention was paid to the inflammation. 

 

Additionally, there was a  diminished "fight-or-flight" stress response and more "rest-and-digest" resulting with attention paid to the inflamed site. Activity from the vagus nerve which connects the brain to essential organs connecting  to 200,000 nerve fibres running on either side of  the neck, reduces inflammation when stimulated.  

"By thinking about, 'This inflammation is hurting me', you're actually ramping up the input of the inflammation to the nervous system, which in turn may be ramping up the output to turn it off."

"It's a very reasonable hypothesis now. that the stimulation of the vagus nerve somehow contributes to the decreased inflammation in the skin of the arm [in this experiment]."

Kevin Tracey, president, CEO, Feinstein Institutes for Medical Research  

Illustrative: A woman having shoulder and neck pain (kieferpix; iStock via Getty Images)

 

"We tend to think of the immune system, injury, or inflammation resolution as something that can take care of itself without any involvement of any high cognitive function. But what happens if the mind focuses on the pain? Does directing the brain toward the injury actually impact its healing? That’s never been studied in humans before." 

"Within less than 20 seconds, you already see the response. It’s sort of like the skin has been stung by something. There’s a bump in the middle, and a flare-up or redness all around it."

"[The inflammation lasts about 20 to 30 minutes, and then it resolves quickly]."

"We simply told them to pay attention to sensations arising from the inflamed site. If attention draws away from it, then bring your attention back. We did the same thing when they were distracted, explaining that if their attention wandered, to return to what was happening on the screen." 

Liron Rozenkrantz, principal investigator, Azrieli Faculty of Medicine