Interoceptive Breathing Perceptions with Anxiety

Background Interoception (i.e. the sensing, processing, and evaluation of signals originating from within the body) has emerged as a key process linked to anxiety, sharing both neural and physiological substrates. The current project examined how anxiety is related to subjective measures of sensitivity towards two different interoceptive breathing modalities, inspiratory resistance and hypercapnia (elevated carbon dioxide; CO 2 ), across a spectrum of anxiety levels. Methods Participants (n = 75) completed self-report measures of anxiety and related variables before undergoing two breathing perception tasks involving graded increases in inspiratory resistance (10, 20, 30 cmH 2 O/L/s) and hypercapnia (2%, 4%, 6% CO 2 ). Perceptual responses (sensory via breathlessness ratings and affect via anxiety ratings) at each step were recorded using visual analogue scales. Data were analysed in STATA using linear mixed effects regression models to assess the variance associated with anxiety status, stimulus level, and their interaction. Additional exploratory correlation analyses were also performed between the perceptual, physiological and anxiety-related measures. Results Primary analyses indicated that anxiety was associated with increased overall affective ratings (resistance: β = 3.83, p < 0.05; CO 2 : β = 3.28, p < 0.05) but not sensory ratings. However, anxiety did not influence participants’ sensitivity to changes in stimulus intensity (i.e. slope) for either inspiratory resistance or hypercapnia. Additionally, anxiety did not relate to ventilatory responses during either stimulus. Exploratory analyses revealed additional correlations including lower self-efficacy relating to altered ventilation during both tasks. Conclusions Overall, these findings suggest that anxiety is primarily associated with increased overall affective perceptions of breathing-related interoceptive signals but does not alter the sensory ratings nor ventilatory responses. This dissociation highlights potential markers for anxiety vulnerability and may inform the development of targeted interventions that focus on specifically modifying affective responses to bodily sensations.