Psychological Inflexibility and HF-HRV reactivity to laboratory stressors

Abstract

Psychological Inflexibility (PI) is a key component of the Unified Flexibility and Mindfulness Model. Higher levels of psychological Inflexibility have been associated with poorer wellbeing. High Frequency Heart Rate Variability (HF-HRV) is a reliable and valid index of vagal activation and wellbeing. The association between Psychological Inflexibility and HF-HRV has been examined in the context of laboratory-induced stressors that evoke different patterns of cardiovascular activation. The present sample included 81 US undergraduate students comprised of 44 females and 37 males (4 did not identify their gender) with a mean age of 19.9 (SD = 2.79) Participants were assigned to view a 3-min video that elicited an orienting response and complete a 3-min math task that elicited a defensive response. The order of stimulus exposure was counterbalanced. Psychological Inflexibility was measured using subscales from the Five Facet Mindfulness Questionnaire using the Unified Flexibility and Mindfulness Model as a guide for scoring. Higher Psychological Inflexibility participants, relative to lower Psychological Inflexibility participants, had a significantly smaller increase in HF-HRV during the orienting stressor indicating less vagal activation. Higher Psychological Inflexibility participants also had a larger decrease in HF-HRV in response to the defensive stressor indicating greater vagal withdrawal. These results shed light on the interactions between Psychological Inflexibility, HF-HRV reactivity to laboratory stressors.