Improving perception of air flow obstruction in asthma patients.

OBJECTIVE The objective of the study was to train asthma patients to improve their ability to discriminate added resistive loads. METHODS Training consisted of a task in which patients judged the relative difficulty of breathing through two circuits. Difficulty of breathing through the circuits was varied by addition of resistive loads. We assigned 45 patients randomly to one of three conditions: a feedback plus fading condition, a feedback condition, and a control condition. RESULTS Feedback of accuracy of judgments coupled with fading resulted in reduction of difference threshold. Neither feedback alone nor a control condition in which patients were given experience in making judgments without feedback resulted in threshold change. CONCLUSIONS Perception training with added resistive loads may help patients to detect an increase in air flow obstruction due to asthma before it becomes severe.