Brains of individuals with asthma may be overly responsive to emotional and physiological signals related to their disease, which may exacerbate inflammation and breathing problems, researchers say.
Studies have shown that asthmatic responses to allergens can worsen during stressful times. Richard Davidson and colleagues looked explicitly at the brain's role in these responses.
Six patients with asthma were given ragweed or dust-mite extracts to inhale and were then told particular speech words. Three types of words were told to the patients: asthma-related (such as "wheeze"), non-asthma negative (such as "loneliness"), and neutral (such as "curtains"). The researchers examined the patients' brain responses via functional magnetic resonance imaging (fMRI).
Two particular areas of the subjects' brains showed more activity with asthma-related words than with other words. This activity was specifically related to physiological signals from the inhaled allergens, the researchers determined.
One brain region has a role in obtaining information about the body's physiological condition, such as shortness of breath, and the other region relates to processing emotional information.
Other brain regions are likely involved in the asthma-stress interaction, the researchers say, but these results suggest potential avenues for treating asthma and other stress-responsive disorders.
The findings are published in the Online Early Edition of Proceedings of the National Academy of Sciences.
