Scientists changed how people breathed and watched their brains respond — the unexpected finding could explain why we make different choices under pressure

Breathing is something people do thousands of times a day without thinking about it. Yet a new study suggests that deliberately changing the way we breathe may do more than help us feel calm.

Researchers have found evidence that the rhythm of breathing can influence how the heart and brain work together during decision-making, potentially affecting how willing people are to take risks.

The study, led by researchers from the German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE) and Charité – Universitätsmedizin Berlin, found that extending the exhalation phase of breathing increased heart rate variability and altered activity in brain regions involved in processing rewards.


Participants who used a slower breathing pattern also tended to make bolder choices in risky situations.

The findings, published in the journal Neuron, offer a new look at the relationship between breathing, the cardiovascular system and the brain.

Why something as simple as breathing could matter

Decision-making is often treated as a purely mental process.

When faced with a difficult choice, people typically weigh information, estimate possible outcomes and decide which option appears most favourable.

But the brain does not operate separately from the rest of the body.

Heart rate, breathing, stress responses and other signals constantly travel between the body and brain. Researchers studying this connection have increasingly become interested in whether changing those physical signals can influence the way people think.

The latest study examined whether consciously controlling breathing could actually alter that process.

Researchers tested a slow breathing pattern

The research team studied 41 healthy adults as they completed a series of decisions involving potential risks and rewards.

Participants were placed under carefully controlled breathing conditions. In one condition, they followed their normal breathing rhythm. In another, they deliberately slowed their breathing while making their exhalation substantially longer.

The specific breathing pattern used an approximately 2:8 inhale-to-exhale ratio.

While the participants made decisions, researchers simultaneously monitored their physiological and brain responses.

Functional MRI scans were used to measure activity inside the brain. The researchers also tracked breathing, heart activity, skin conductance and changes in pupil size.

This allowed them to examine what was happening throughout the body while participants evaluated risky choices.

Longer exhales were linked to bolder decisions

The results revealed a notable change.

When participants used the extended-exhalation breathing pattern, their heart rate slowed and their choices shifted towards greater risk-taking.

But the researchers found that this did not appear to happen because participants simply became less sensitive to losses.

Instead, the breathing intervention appeared to make them more responsive to potential rewards.

That distinction is important.

Someone taking greater risks because they have stopped worrying about losing something is behaving differently from someone who becomes more willing to take a chance because the possible reward appears more attractive.

According to the researchers, the latter pattern better described what they observed.

The heart and brain appeared to change together

The researchers also identified changes in brain activity associated with the altered breathing pattern.

Greater activity was observed in areas including the ventromedial prefrontal cortex and precuneus, regions that have been linked to reward processing and decision-making.

The findings were also associated with changes in heart rate variability, a measure of the variation in time between individual heartbeats.

Heart rate variability is often used as an indicator of how the autonomic nervous system is regulating the cardiovascular system.

Taken together, the results suggest that the effect of controlled breathing may involve more than simply slowing the heartbeat.

Instead, changing the breathing rhythm may alter cardiovascular signals that are then reflected in how the brain evaluates potential outcomes.

Stress can change the way people make choices

The findings may help explain why people's decisions can change dramatically depending on their physical and emotional state.

Under pressure, the body can enter a heightened state of arousal. Breathing becomes faster, the heart beats more rapidly and attention can become focused on immediate threats.

That can influence how a person evaluates risk.

The opposite state may produce a different pattern. Slower breathing and a calmer cardiovascular response could make potential rewards more prominent during decision-making.

The researchers' findings suggest that the relationship may be more direct than previously appreciated: changing the body's state through breathing could, in turn, change how the brain processes a choice.

Could breathing exercises affect everyday decisions?

Controlled breathing techniques have been practised for centuries in different cultures and traditions.

They are often associated with relaxation and stress management, but the new research points towards another possible role: influencing how people evaluate rewards and risks.

That does not mean that taking a few slow breaths will automatically make someone a better decision-maker.

The experiment involved a relatively small group of healthy participants and was conducted under controlled laboratory conditions.

Whether the same effects occur during everyday decisions — such as financial choices, workplace situations or interpersonal conflicts — remains to be established.

The researchers say further work will be needed to determine how broadly the findings apply.

Researchers are interested in eating behaviour

One area the team wants to investigate next is food-related decision-making.

Eating is heavily influenced by reward. People do not choose food based solely on nutritional information; taste, cravings, emotions and physiological state can all influence what they decide to eat.

Because the study suggests that breathing can alter how the brain responds to potential rewards, the researchers want to know whether controlled breathing could also affect food choices.

This could be particularly relevant to research into eating behaviour and weight management.

However, any potential application would require considerably more evidence before breathing techniques could be considered an established intervention for such conditions.

What the study reveals about the body-brain connection

The bigger significance of the research may lie in what it says about the relationship between the body and the brain.

For a long time, decision-making was largely studied as a function of cognitive processes occurring inside the brain.

Increasingly, researchers are finding that the brain is continuously receiving information from the heart, lungs and other organs.

Breathing provides an unusually accessible way to influence some of those signals.

Unlike many biological processes, breathing can be consciously controlled almost immediately. That makes it an interesting tool for researchers studying how physiological changes affect cognition.

The new study adds evidence to the idea that the way we breathe may influence not only how calm or alert we feel, but also how our brains evaluate choices.

A simple breathing change, but a complicated biological effect

The researchers are not suggesting that breathing is a magic switch for human behaviour.

Instead, the study points to a more subtle mechanism in which breathing, heart activity and brain function interact.

A longer exhalation altered cardiovascular dynamics. Those changes were associated with activity in brain regions involved in reward processing, while participants became more willing to choose riskier options.

Whether this mechanism can eventually be harnessed for practical applications remains an open question.

For now, the findings provide an intriguing reminder that some of the processes we usually take for granted may be influencing our decisions in ways we barely notice.

Every breath may be automatic, but scientists are finding that its rhythm could have a much bigger role in the brain than previously understood.