Mind Games

All in Our Heads

Back when the Azrieli Faculty of Medicine’s Dr. Liron Rozenkrantz was pursuing her undergraduate degree in neuroscience at Bar-Ilan, she kept returning to one question: Why should we stop there? “There,” in this instance, was the study of the effects of our mental processes, such as beliefs and expectations, on the physiological processes that cause pain. Or, in simpler terms, the placebo effect. “Already back then, we understood the neurobiological mechanisms at work in blocking pain in the spinal cord,” says Rozenkrantz. “But I wanted to know, why aren’t our beliefs having neurobiological effects in every area of life? And if they are, why aren’t we trying to harness those beliefs to improve our health and well-being?”

After a Ph.D. at the Weizmann Institute, postdoctoral research at MIT, and a fellowship in the Program in Placebo Studies at Harvard University, Rozenkrantz is now doing just that in her Psychobiology of Beliefs Lab, which studies people’s behavior, physiological responses, hormonal levels, and blood biomarkers to determine how beliefs influence our metabolic processes (“Believing that a certain food is nourishing can lead us to feel full, biologically speaking,” Rozenkrantz explains, “even if it has no more calories or nutrients than another, lesser option”) and immune systems. In the case of the latter, the Covid-19 pandemic provided the perfect conditions: In a study of hundreds of patients who had yet to contract the virus, Rozenkrantz showed that simply believing that one is likely to develop severe symptoms makes the development of those symptoms more likely. Indeed, perceptions about the robustness of our own immunity—more than anxiety about the virus itself, or the fear of infection—predicts our experience of symptoms with remarkable accuracy. Rozenkrantz developed these findings into a “Perceived Immunity Scale,” a tool that measures the interplay between our beliefs about our immunity and our day-to-day health. Her work, which was published last May in the prestigious British Journal of Health Psychology, can help both researchers and healthcare providers when studying and selecting treatments for both acute and chronic illness.

“Today, there’s a huge emphasis on improving preventive health measures such as diet and exercise. But what we’re learning is that improving our health beliefs is no less critical to our well-being,” says Rozenkrantz. “We believe that altering our health beliefs can affect our ability to manage chronic illness, obesity, even depression. But you don’t have to take our word for it,” she says with a smile. “We have the neurobiological evidence to prove it.”