A new study published in Nature Human Behaviour suggests that directing attention to bodily sensations can dampen acute inflammatory responses in humans. The research, led by Nofar Mizrachi and Liron Rozenkrantz of Bar-Ilan University’s Azrieli Faculty of Medicine, proposes that voluntary cognitive processes can influence immune regulation previously considered automatic.
Acute inflammation is the body’s rapid, protective response to injury or irritation, characterised by local heat, swelling and redness. In the laboratory, scientists trigger this process using histamine—a chemical released during allergic reactions that widens blood vessels and causes fluid leakage. The resulting wheal (a raised bump) and flare (the surrounding redness) provide a readout of the body’s inflammatory response.
The researchers designed three pre-registered experiments to test whether conscious attention to bodily signals could alter this immune reaction. In the first, 37 healthy adults received a histamine prick on the forearm across two sessions. In one, participants were instructed to stare at a screen and focus attention on the skin sensations from the arm. In the other, they watched engaging video clips to distract their attention from the site, while the skin response was recorded over 20 minutes.
The observer conducting the skin measurements was blind to which condition each participant experienced, and session order was balanced. Participants were not told the study’s purpose, and when asked to guess the aim at the end, only 14 per cent correctly identified it.
The findings were striking: focusing attention on the arm markedly reduced the inflammatory reaction. At the 20‑minute peak, the swelling averaged 3.5 millimetres under internal attention compared with 5.0 millimetres during distraction, a roughly 1.5-fold difference. Redness followed a similar pattern, averaging 10.6 millimetres under internal attention versus 14.0 millimetres with distraction, though the redness did not fade on a different timeline than the swelling.
About nine in ten participants showed a larger swelling reaction when attention was directed away from the arm. In a supplementary analysis—not part of the pre-registered plan—nearly 90 per cent displayed swelling that had stopped growing or begun to shrink by 20 minutes during internal focus, compared with 46 per cent during distraction.
To rule out the influence of video content, a second experiment with 20 new participants used an identical geometric slideshow of 37 shapes. In the internal‑attention condition, each new shape served as a cue to re‑focus on the itching sensation; in the distraction condition, participants evaluated whether each shape could exist in real life.
With the same visual input and matched mental effort, the effect persisted. Swelling and redness were around 1.6 times smaller when participants attended to their arm sensations rather than assessing the abstract shapes. The pattern that 90 per cent of participants exhibited larger reactions under distraction again held true. Notably, participants reported that the itching and burning felt stronger under focus, even as the immune response was smaller.
“What I find most surprising is that a process as basic and fundamental as acute peripheral inflammation is affected by cognition at all,” Rozenkrantz noted. “Inflammation is generally thought of as an autonomous physiological process, largely independent of cognition, so finding that something as voluntary as where we direct our attention can participate in its regulation really challenges that separation between cognition and basic bodily regulation.”
The researchers then asked whether sensory feedback from the skin was necessary for the brain to regulate swelling. In a third experiment, 17 participants returned after a prior session and received a topical lidocaine to dull nerve signals at the test site. The peak swelling under internal attention rose to 4.0 millimetres with numbness, compared with 3.1 millimetres in the earlier internal condition, while numbness also slowed recovery toward baseline.
Despite the dampened sensory input, the internal‑attention condition remained smaller than the distraction condition, which averaged 4.9 millimetres. This suggested that while sensory signals contribute to the regulation of swelling in later stages, attention may regulate the response through other pathways when local sensation is reduced. It also appeared that perceived itching ratings did not differ significantly between the numb and distraction conditions, implying that sensation alone did not dictate the outcome.
The researchers monitored the autonomic nervous system to probe how the brain might communicate with the skin. Measures tied to the fight‑or‑flight branch—such as skin conductance, heart rate and skin temperature—showed no significant differences between conditions, and participants’ anxiety scores did not differ meaningfully either.
However, heart rate variability—the fluctuation in the interval between heartbeats, linked to the calming “rest and digest” branch via the vagus nerve—was modestly higher during internal attention. This difference persisted even when the skin was numbed, which the authors interpret as consistent with the vagus nerve’s anti-inflammatory pathway engaging independently of local sensory signals.
Independent expert feedback varied in tone. Professor Warren Mansell, director of the LEx Mental Health Research Group at Curtin University, who was not involved in the study, said: “What I find most surprising is that a process as basic and fundamental as acute peripheral inflammation is affected by cognition at all.” He added that the findings “raise the possibility that through willingly attending to unpleasant feelings in our bodies, we may support our body’s immune reaction to it. It also raises the possibility that chronically distracting ourselves from distress in our body may undermine our immune system.”
Mansell cautioned against overinterpreting the results, noting that distraction can still be a useful short‑term strategy for managing discomfort even if it is not beneficial for longer‑term physiological restoration. He also pointed out that the study’s focus on involuntary worry-related bodily sensations is different from the voluntary attention examined here, and that drawings of broader clinical implications remain premature.
The authors emphasise that this is an initial demonstration in a tightly controlled experimental model. They warn against extrapolating to chronic inflammation, disease, wound healing or whole-body illnesses, and stress that the observed effects are modest and context-specific.
They also acknowledge limitations, including small sample sizes across the experiments and a participant pool that was predominantly young women in the third study. The researchers did not measure specific immune cells or signalling molecules, leaving the precise biochemical steps unresolved, and the lidocaine approach may not block every nerve fibre involved.
Looking ahead, the study’s authors say the key question is how broadly attention can regulate physiological processes. They envisage future work to test the impact of more extensive training on more global and enduring indices of immune functioning, and to explore where and when attention might shape other bodily responses.
“What excited us most is how many new questions this opens up,” Rozenkrantz said. “If attention can participate in regulating inflammation, what other physiological processes might it influence? When does this happen, for whom, and under what conditions? And eventually, how might we harness it clinically?”
The study, Voluntary attention regulates acute immune responses in humans, was authored by Nofar Mizrachi, Menachem Rottem and Liron Rozenkrantz.
