title: Fearful responding to repeated CO2 inhalation: a preliminary investigation.
abstract: In an effort to explore factors which maintain fear of physical sensations, repeated administration of 35% CO2 was used with college students scoring high and low on the Anxiety Sensitivity Index. Half of each group was administered 12 CO2 trials, while the other half received 9 CO2 trials, followed by a dishabituation trial (Trial 10) and 2 more CO2 administrations (Trials 11 and 12). Measures included subjective anxiety, heart rate, skin conductance, and number of panic symptoms reported. Results indicated a nonsignificant trend for the High ASI group to show increased pre-inhalation anxiety across trials, while the Low ASI group showed a rapid reduction in pre-inhalation anxiety. Post-inhalation skin conductance mirrored this pattern, although rapid reduction in post-inhalation heart rate was observed. Overall, the High ASI participants showed a notable lack of fear reduction across trials. Results are discussed in light of sensitization as a factor contributing to anticipatory anxiety, with implications for understanding the etiology and maintenance of Panic Disorder.
authors.affiliation: Department of Psychology, State University of New York at Buffalo 14260, USA.
authors.forename: J G
authors.initials: JG
authors.lastname: Beck
authors.forename: J C
authors.initials: JC
authors.lastname: Shipherd
authors.forename: B J
authors.initials: BJ
authors.lastname: Zebb
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001008:Anxiety Disorders / Q000503:physiopathology*; D002245:Carbon Dioxide / Q000009:adverse effects*; D005260:Female; D006185:Habituation, Psychophysiologic / Q000502:physiology*; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D016584:Panic Disorder / Q000503:physiopathology; D012677:Sensation / Q000502:physiology
chemical_list: D002245:Carbon Dioxide