Researchers Study Self-Knowledge (Literally): The Body Sends Cues to the Brain; Understanding Them Can Improve Your Health

August 26, 2013, 6:59 p.m. ET

Researchers Study Self-Knowledge (Literally)

The Body Sends Cues to the Brain; Understanding Them Can Improve Your Health

SHIRLEY S. WANG

How well do people know their bodies and how does that help them function day to day? The attempt to understand how humans make sense of all the complex feedback they receive from the eyes and ears down has taken off and reached a new level of understanding in the last decade. One prong of the research being conducted in the United Kingdom, Germany, the U.S. and elsewhere is focused on understanding how well brains detect and react to cues from inside the body.Studies have found that people who can better read their internal physical sensations, a skill called interoceptive awareness, have a clearer sense of their physical and mental selves, including an ability to experience emotions more strongly and are better able to control them. They also may have a lower likelihood of certain conditions like unexplained pain (pain without an obvious source), depression, eating disorders and panic attacks, according to researchers.

“Being in touch with your body might allow you to perceive bodily changes…and this might help you to respond earlier or might make you more flexible in [emotion] regulation strategies,” said Olga Pollatos, the head of the health psychology department at the University of Ulm in Germany who has conducted extensive research in this area. For instance, the ability to better detect that you are stressed out means that you could react sooner by going to the gym or thinking about something pleasant.

Researchers hope to chart a path to improved care for eating disorders and other mental conditions involving how people seem more out of touch with their bodies.

One group of interest are people who suffer from pain that doesn’t have an obvious source. Experts used to think that such pain sufferers were more acutely sensitive to their bodies and more cued in to detecting pain, but recent work has shown otherwise. Dr. Pollatos and her team studied a group of people with unexplained pain, asking the subjects to report their heart rate by sitting quietly for intervals of time and focusing on their body without feeling for their pulse. Their actual heart rate was measured at the same time. People who are more accurate in their assessment of their heart rates are considered to have better interoceptive awareness.

The researchers found that these unexplained pain sufferers were actually worse than a control group at detecting their heart rate. Their low awareness suggests they may have more trouble differentiating between different bodily sensations, including where the source of the pain is originating, says Dr. Pollatos. Instead of feeling hurt after being socially excluded, for example, these individuals may misread the same bodily signals as physical pain, which could help explain why they experience continued and diffuse pain. Similarly, misinterpretation of bodily sensations may play a role for people who get panic attacks.

“Training these patients to be able to differentiate between different bodily responses and to stop this vicious circle of misinterpreting these sensations as potentially harmful is one avenue this research might take,” said Dr. Pollatos.

In another study published last year, her team found that healthy people who were higher in interoceptive awareness were more sensitive in detecting painful stimulation. This might help them to react to physical pain in everyday situations earlier and therefore prevent injuries, Dr. Pollatos said.

Greater interoceptive awareness also appears to mitigate risk-taking behavior, Dr. Pollatos’s research and that of others has shown. In studies in when people were asked to play a game in which they win or lose money, those in tune with their bodies engaged in less risky behaviors, perhaps because they were better at reading feedback suggesting anxiety, such as a pickup in heartrate or increased sweating from their bodies.

“If you rely on a gut feeling and have better access to that gut feeling, it might make you more cautious,” said Dr. Pollatos.

Tapping into the brain’s ability to detect and integrate complex sensory information may also be useful therapeutically. Jane Aspell, a psychology professor at Anglia Ruskin University in the U.K., showed that people could identify with a virtual silhouette of themselves by tricking the brain with sensory cues to identify with the image, in this case by having the silhouette pulse in time with the individual’s heartbeat. She expects to publish the research soon in the journal Psychological Science.

One recent afternoon, a woman was given virtual-reality glasses that allowed her to see a silhouetted image of her back, captured by cameras behind her, appearing to stand in front of her. A white line bordered the edge of the projected image.

Dr. Aspell then manipulated the white border to flash either in time with the patient’s heartbeat, which was being measured by an electrocardiogram, or at a different rate. When the silhouette pulsed in time with the participants’ hearts, the individuals reported “feeling” more like they were their virtual-reality selves. The participants didn’t know why the silhouette was pulsing—and none suspected it was linked with their heartbeat.

Such a technique may one day be able to be applied to people who may be disconnected from their physical bodies, such as those with anorexia, who often view themselves as bigger than they are, Dr. Aspell said.

This area of work represents a shift in thinking that suggests a more complex relationship between mind and body than the classic top-down model that pictures the brain in full control. In the new framework, the brain can’t be separated from the body; it is motivated by reacting to and making sense of changes in heart rhythm, blood chemistry, breathing and muscle tension.

This “symphony of changes” also leads the brain to register emotions, according to Antonio Damasio, a professor of neuroscience at the University of Southern California, who is studying the cellular basis of feelings, among other projects.

Training people to be more aware of what their bodies tell them, or at least of their heartbeat, has proved difficult so far. Merely teaching people to be more conscious, such as through meditation, seems to have little to no impact on their ability to actually be in tune with their heart rate.

One study, published in Physiology in 2009, examined experienced meditators, Tibetan Buddhist and Kundalini monks, found no evidence that they were any better at detecting their heart rates than non-meditators.

Vivien Ainley, a graduate student in the psychology department of Royal Holloway University of London, is also studying this question and she and her colleagues have made some progress by using a mirror.

They asked 150 individuals to count their heartbeats while staring at themselves in a mirror. People who measured particularly low in awareness did better than when doing the same task staring at a blank screen. Perhaps the mirror affords more visual cues, or individuals find themselves concentrating harder on the body when they see themselves, Ms. Ainley said.