The present article aims to illustrate and review evidence on how associative learning involving interoceptive stimuli (interoceptive conditioning) can lead to changes in physiological, emotional, and perceptual outcomes. We first outline a functional perspective on Pavlovian conditioning and provide a general introduction and historical background on interoceptive conditioning as a special instance of Pavlovian conditioning. Next, biological and learning accounts of panic disorder are discussed, followed by an analysis of which stimuli and responses may be most promising to model learning that is relevant to panic disorder. Finally, studies on interoceptive fear conditioning with respiratory stimuli are reviewed and discussed, and future directions are outlined.
K E Y W O R D Sanxiety, conditioning, interoception, psychopathology, respiration, startle blink BOX 1 Six propositions a 1. Unlike the continuum of exteroceptive stimulation, which is the body material of all our conscious experiences, the continuum of interoceptive stimulation leads largely to unconscious reactions. 2. Interoceptive conditioning, whether involving conditioned or unconditioned interoceptive stimuli, is readily obtainable and is by its very nature largely unconscious in character. 3. While interoceptive conditioning is by its nature more limited than is exteroceptive conditioning with respect to total kinds and variety of stimulations, the interoceptive kinds of stimulations are, on the other hand, by their very nature much more recurrent, periodic, and organism bound, making interoceptive conditioning an almost built-in function that is constantly generated and regenerated in the very process of living and acting. 4. Interoceptive conditioning is somewhat slower in formation than is exteroceptive, but, once conditioned, it is more fixed and irreversible (less readily extinguished). 5. When equal but opposing interoceptively produced and exteroceptively produced reactions are juxtaposed, the interoceptive reactions dominate the exteroceptive ones, with the final result that preceding exteroceptive stimuli become conditioned stimuli for succeeding interoceptive reactions, whereas preceding interoceptive reactions become strengthened by exteroceptive reactions succeeding them. 6. The juxtaposition of conditioned interoceptive and exteroceptive stimuli of the same conditioned reaction, unlike similar juxtapositions of exteroceptive stimuli of different modalities, produces a certain amount of conflict and decrementation of conditioning. a (Razran, 1961, p. 97)