Respiratory factors in clinical psychophysiology and biofeedback

Respiration is a complex physiological system affecting a variety of physic al processes that can act as a critical link between mind and body. In this paper, we discuss the physiology and psychophysiology of breathing and its relevance for understanding several clinical syndromes that are not direct ly associated with respiratory disturbance. We present findings from three areas - panic disorder, functional cardiac disorder, and chronic pain - sup porting respiratory factors as either markers, mediators, or etiological me chanisms for a number of physical symptoms. Recent technological advances a llowing the ambulatory measurement of end-tidal partial pressure of CO2 (pC O(2)), and respiratory patterns have opened up new avenues for investigatio n and treatment of these disorders. Recent evidence from our laboratories i ndicates that subtle but consistent breathing abnormalities are present in panic patients as opposed to other anxiety disorder or normal control group s. Contrary to previous models that emphasized outright hyperventilation as a key factor in anxiety disorders, this research focuses on respiratory in stability and breathing behaviors such as sighs as signs of dysfunctional r egulation of breathing. Finally, we discuss some treatment approaches based on the proposed mediational model that can be effective in the disorders m entioned above.