When wrestling with a moral dilemma, a person may reach a decision not only by thinking through the problem but also by tuning into physical signals from their body, a new study suggests.
The research found that people who are more in tune with their body signals — such as shifts in their heart rate — tend to make moral decisions that align with the judgments that most other people would make if presented the same scenario. These findings suggest that such internal, physical cues could thus play a role in guiding a person’s moral intuition, the study authors said.
“Morality is often viewed as a product of culture and context,” Tamami Nakano, a cognitive neuroscientist at the University of Osaka who was not involved in the study, told Live Science in an email. “Showing that bodily signals actively mediate this calibration is both novel and compelling.”
In short, the study supports the idea that these bodily reactions form part of a feedback loop that helps guide people in their decision making.
What’s more, previous studies have suggested that siding with the majority in a moral dilemma could help take some strain off the brain, and the new study seems to align with that notion, too.
“Recent theories suggest that our brains are designed to minimize physical resource consumption while maintaining survival,” study co-author Hackjin Kim, a neuroscientist at Korea University, told Live Science in an email. “One way to do this [conserve energy] is to learn others’ expectations to avoid social conflict,” Kim suggested. Combining these ideas, Kim and colleagues proposed that people who are better attuned to their bodily feedback signals may use that information to keep their decision-making in line with others’ expectations.
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In their new study, published May 5 in The Journal of Neuroscience, the team tested this hypothesis by presenting participants with moral dilemmas and asking them to choose between two decisions — one “utilitarian,” which prioritized minimizing harm for the most people, and one “deontological,” which prioritized following established rules and norms.
In a separate test, the researchers asked the participants to focus on their bodies and count their heartbeats over a short interval while the participants’ heartbeats were simultaneously recorded with an electrocardiogram.
People who were more accurate at counting their heartbeats also tended to choose the moral decision that most other people chose, the team found. This was true whether more people chose the utilitarian or deontological option for a given moral dilemma.
It may be that cues from a person’s body help signal when the person is about to do something that could run up against social norms — a scenario that requires more energy and effort to navigate, the study authors propose. Basically, it’s easier to go with the flow than run against the grain.
“The idea is that feeling that anxiety is going to make you notice that you did something to cause that anxiety, and then make you try to avoid doing those things in the future,” said Jordan Theriault, a psychologist and biologist at Northeastern University who was not involved in the study. “You feel that feedback from your body, and then you learn not to do that again in the future,” he told Live Science. As Theriault describes, you learn over time what others expect of you morally, and your physical reactions form part of the feedback loop that helps guide future decision making.
In the study, participants responded to each dilemma without knowing which of the two options other people chose. They weren’t pressured into making a certain decision or conforming to what the rest of the group unknowingly agreed upon, so the results reflect each individuals’ moral intuition. Notably, all 104 participants were Korean university students, so it’s possible they shared similar cultural and demographic backgrounds as well as similar moral norms.
The team also studied people’s brains while at rest to determine how much time they spent in different “brain states” — patterns of brain activity associated with different kinds of tasks. The brain switches back and forth between many different states even when a person isn’t doing anything specific.
To track these states, the team used functional magnetic resonance imaging (fMRI), which tracks blood flow as an indirect measure of brain activity. The researchers found that the people who were more aware of their body’s signals tended to spend more time in a brain state associated with evaluation and judgment. This particular state was marked by activity in a brain region called the medial prefrontal cortex, which has previously been linked to the process of adjusting choices to meet other people’s expectations.
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These brain scans may further support the idea that people who are more in tune with their bodily signals use those cues to stay aligned with majority opinion. However, because these data were collected separately from the moral-decision tasks, “we still need task-based evidence showing which specific brain regions process body-related signals when people face real moral dilemmas and how these signals influence behavior in real time,” Nakano told Live Science. This might involve having people contend with moral dilemmas while in an fMRI scanner.
In future work, Kim plans to investigate how the relationship between moral intuition and awareness of body signals varies among cultures, types of moral dilemmas and individual personality differences. But for now, Kim said, “this research lays a new theoretical framework for understanding cultural and individual differences in moral behavior and predicting norm-following behavior in group or online settings.”
