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.
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There is experimental evidence that pharmacological interoceptive exposure therapy can reduce anxiety disorder symptom severity either as monotherapy or as an augmentative approach.
“There is also experimental evidence that pharmacological interoceptive exposure therapy can reduce anxiety disorder symptom severity either as monotherapy (7,121–123) or as an augmentative approach (124).”
From Interoception and Mental Health: A Roadmap. (2018) · cites this paper as [122]
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- Authors
- Forsyth, J. P., Lejuez, C. W., & Finlay, C.
- Affiliations
- University at Albany, State University of New York (US)
- Brown University (US)
- Corresponding author
- Forsyth, John P
- ORCID
- Lejuez, C.W
- Venue
- Journal of Behavior Therapy and Experimental Psychiatry
- Publisher
- Elsevier BV
- Published
- 2000-06
- Volume
- 31
- Issue
- 2
- Pages
- 103-121
- ISSN
- 0005-7916 (ISSN-L)
- OpenAlex
- W2042459543
- Cited by
- 37
- References
- 0
- Citations by year
- 2026: 3 · 2025: 1 · 2024: 1 · 2021: 1 · 2020: 1 · 2018: 1 · 2017: 2 · 2016: 3 · 2014: 2 · 2013: 1
- FWCI
- 1.62
- Type
- journal article
- Language
- en
- Open access
- closed
- Locations
- Journal of Behavior Therapy and Experimental Psychiatry (publishedVersion)
- PubMed (publishedVersion)
- Topics
- Social Sciences › Psychology › Experimental and Cognitive Psychology › Anxiety, Depression, Psychometrics, Treatment, Cognitive Processes
- Life Sciences › Neuroscience › Cognitive Neuroscience › Memory and Neural Mechanisms
- Health Sciences › Medicine › Psychiatry and Mental health › Psychosomatic Disorders and Their Treatments
- Keywords
- anxiety, habituation, sensitization, panic, anxiety sensitivity, interoceptive exposure, panic disorder, autonomic responses, cardiac response, individual differences
- MeSH terms
- Adolescent, Adult, Arousal, Autonomic Nervous System, Carbon Dioxide, Conditioning, Classical, Female, Galvanic Skin Response, Habituation, Psychophysiologic, Heart Rate, Humans, Male, Panic
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