Repeated experiences of air hunger and ventilatory behavior in response to hypercapnia in the standardized rebreathing test: effects of anxiety.
In this study, we assessed air hunger (AH) and ventilatory responses to repeated CO(2) exposures in healthy women (N=31), scoring high or low for trait anxiety. A standardized rebreathing test, implying a gradually increasing CO(2) stimulus, was administered three times with 15-min intervals. Respiratory behavior and the intensity of AH perception were measured continuously. Across repeated exposures, maximal tolerance for AH habituated and the slope of AH (increase in AH per unit increase in CO(2)) diminished. Also the dynamics of the breathing response changed across trials. The thresholds for AH and tidal volume (V(T)) moved closer to each other, whereas the threshold for the respiratory rate (RR) was generally postponed. In addition, the association between AH and V(T) was stronger than between AH and RR, and the latter association became weaker over trials, particularly in high anxious persons. This suggests that AH perception became increasingly influenced by psychological factors, especially in high anxious persons. The results suggest that habituation of perceived air hunger is depending on a complex interplay between both changes in respiratory behavior and in perceptual-cognitive processes related to trait anxiety.
Wan
Li
L
Department of Psychology, University of Leuven, Leuven 3000, Belgium.
Van Diest
Ilse
I
De Peuter
Steven
S
Bogaerts
Katleen
K
Oyen
Natalie
N
Hombroux
Nele
N
Van de Woestijne
Karel
K
Gallego
Jorge
J
Van den Bergh
Omer
O
D000293:Adolescent; D000328:Adult; D001007:Anxiety / Q000503:physiopathology* / Q000523:psychology*; D002245:Carbon Dioxide; D005221:Fatigue / Q000523:psychology; D005260:Female; D006801:Humans; D006935:Hypercapnia / Q000503:physiopathology* / Q000523:psychology*; D012129:Respiratory Function Tests; D015656:Respiratory Mechanics / Q000502:physiology*; D013990:Tidal Volume / Q000502:physiology
D002245:Carbon Dioxide