title: Anxiogenic effects of repeated administrations of 20% CO2-enriched air: stability within sessions and habituation across time.
abstract: Increasingly carbon dioxide-enriched air is being used as an aversive unconditioned stimulus in laboratory examinations of anxiety. Yet, little is known about the stability of the autonomic and subjective effects of this stimulus across repeated inhalations and sessions. We examined whether repeated administrations of high concentrations of CO2-enriched air produced either habituation, stability, or sensitization across several autonomic and self-report indices within one session (Experiment 1) and then several sessions (Experiment 2) of exposure. Results suggest that non-clinical participants do not habituate to CO2 within sessions, but do show habituation on cardiac and subjective report of anxiety across sessions. Individual difference factors such as anxiety sensitivity and suffocation fear seem to moderate some of these effects, including self-reported distress and anxiety in response to the challenge. These results support the use of CO2 as a panicogenic aversive stimulus in laboratory models of fear onset and in clinical settings for interoceptive exposure treatments of panic.
authors.affiliation: Department of Psychology, University at Albany, State University of New York, 12222, USA. forsyth@csc.albany.edu
authors.forename: J P
authors.initials: JP
authors.lastname: Forsyth
authors.forename: C W
authors.initials: CW
authors.lastname: Lejuez
authors.forename: C
authors.initials: C
authors.lastname: Finlay
mesh_terms: D000293:Adolescent; D000328:Adult; D001143:Arousal / Q000187:drug effects*; D001341:Autonomic Nervous System / Q000187:drug effects; D002245:Carbon Dioxide / Q000494:pharmacology*; D003214:Conditioning, Classical; D005260:Female; D005712:Galvanic Skin Response / Q000187:drug effects; D006185:Habituation, Psychophysiologic / Q000187:drug effects; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D010200:Panic / Q000187:drug effects
chemical_list: D002245:Carbon Dioxide