Probing the psychophysiology of the airways: physical activity, experienced emotion, and facially expressed emotion.

This article reviews research on airway reactivity in health and asthma within a psychophysiological context, including the effects of physical activity, emotion induction, and manipulation of facial expression of emotion. Skeletal muscle activation leads to airway dilation, with vagal withdrawal being the most likely mechanism. Emotional arousal, in particular negative affect, leads to airway constriction, with evidence for a vagal pathway in depressive states and ventilatory contributions in positive affect. Laboratory-induced airway responses covary with reports of emotion-induced asthma and with lung function decline during negative mood in the field. Like physical activity, facial expression of emotion leads to airway dilation. However, these effects are small and less consistent in posed emotional expressions. The mechanisms of emotion-induced airway responses and potential benefits of emotional expression in asthma deserve further study.