Each one of us goes through life constantly bombarded with situations that test our character, morals, and mental stamina. These situations — whether it’s an argument with a family member, a break-up, or a difficult boss — often test us, and the result is we become defensive. We stick to how we’ve learned to deal with situations (often with hardheadedness) even when that situation no longer exists. While this isn’t necessarily a bad thing, it sometimes makes people forget how to be reasonable; they shut themselves into their own bubble of living. A new study, however, suggests self-affirmation can tap into these people’s brains, making them more receptive.

Specifically focusing on health advice, researchers from the University of Pennsylvania’s Annenberg School for Communication were interested in seeing how they could convince people to take steps toward a healthier lifestyle without becoming defensive. Studies have shown that when people are faced with information that contradicts their way of living, the parts of their brains that handle reason and logic stop working, while the areas responsible for a fight-or-flight response become active. The researchers found people can take a step back from that response, and take productive action, if the criticism they’re receiving is paired with a message of self-affirmation.

“Self-affirmation involves reflecting on core values,” said Emily Falk, lead author of the study and director of the Communication Neuroscience Laboratory at the University of Pennsylvania’s Annenberg School for Communication, in a press release. Those core values can vary depending on the person, but they always reflect that person’s sense of self-worth, whether it’s being helpful toward friends and family, being creative, or cooking.

By reminding them they’re valuable in some way, the part of the brain responsible for emotional responses, decision-making, and determining how much value to place on an idea — the ventromedial prefrontal cortex (VMPFC) — becomes active, and that advice or criticism comes off as less of an attack and more of a note that we can all improve ourselves a bit more. “Our work shows that when people are affirmed, their brains process subsequent messages differently,” Falk said.

With a group of 67 sedentary adults, the researchers found these reminders were effective in passing on advice encouraging a more active lifestyle. Each participant wore an activity-tracking device on their wrist for a week before the intervention and a month after. The intervention involved undergoing a functional magnetic resonance imaging (fMRI) scan while hearing health messages like, “According to the American Heart Association, people at your level of physical inactivity are at a much higher risk of developing heart disease.” Other messages gave suggestions on how to live healthier (“After an hour of sitting, try standing for five minutes”), and some participants also got self-affirming messages like, “Think of a time when you will help a friend of family member reach an accomplishment.”

Participants who heard both types of messages showed not only more activity in their brains’ VMPFC, but they were also more likely to follow the advice they were given for the month following the messages. “Our findings highlight that something as simple as reflecting on core values can fundamentally change the way our brains respond to the kinds of messages we encounter every day,” Falk said. “Over time, that makes [a] potential huge impact.”

Over two-thirds of Americans are considered overweight or obese, according to the National Institute of Diabetes and Digestive and Kidney Diseases. Yet, a Gallup poll from last year found 55 percent of Americans don’t think they’re overweight, and are thus not actively taking steps to be healthy. The new findings could make it easier to approach these people with life-changing advice.

Source: Falk E, O’Donnell M, Cascio C, et al. PNAS. 2015.