FRIDAY, Jan. 23, 2004 (HealthDayNews) -- People who are highly sensitive to their heartbeat and other internal "body states" tend to experience more anxiety and other negative emotions on a daily basis.
So says a new British study in the February issue of Nature Neuroscience.
But that heightened sense of awareness may not be such a bad thing, says a neurology expert familiar with the research.
In their study of 38 people, scientists found those who showed the most activity in a certain region of the brain while performing a task that measured their body awareness were prone to more anxiety and other "negative emotions" in daily life. The task asked the people to determine whether their heartbeat was synchronized with a series of tones.
The researchers, from University College London and Karolinska Hospital in Stockholm, also found the brain region -- called the right anterior insular cortex -- tended to be bigger in the more self-aware people.
The new finding, the authors note, lends credence to previous research that found the region controls awareness of emotions.
The researchers used functional magnetic resonance imaging to evaluate how the participants' internal body responses were mapped in the brain. The participants were also given questionnaires about their anxiety levels and other symptoms to evaluate how their awareness of body states correlated with their emotions.
Another expert in the field finds the new research important and "surprising," and offers the following perspective: "The idea that the subjective experience of emotion reflects awareness of internal body states is not new," says Antoine Bechara, an assistant professor of neurology at the University of Iowa. The idea was suggested more than a hundred years ago.
But it has been controversial within neuroscience circles, Bechara says, and some experts did not believe it. The new study, he says, provides hard evidence that the theory is true. "The evidence is based not only on functional neuroimaging, but also on measuring the size of a specific brain region, the anterior insular cortex."
"The finding that people who are more aware of their internal body states, and tend to experience more anxiety and negative emotions in daily life, have a larger size anterior insular cortex is a first," Bechara says.
"If this hyperawareness is within the normal range, then I would say that it is a good thing and it should not be controlled at all," Bechara adds. "In fact, I say that it is an advantage like having a very high IQ."
Many people are taught that emotions such as anxiety are bad because they can interfere with good judgment, Bechara says. But evidence from patients with certain types of brain damage in which emotions are wiped out proves the opposite, he says. Those with abnormally low levels of awareness, Bechara says, have diminished "emotional" and "social" intelligence.
"I would say that it is not good at all to try to be less aware of one's own internal body states," Bechara adds.
However, if that awareness becomes extreme and anxiety and other negative emotions disrupt normal routines, the person should seek professional help, he says.