Autonomic patterns for presence and absence : an idiographic investigation of mind-body dynamics

Abstract

This dissertation investigated autonomic physiological correlates of two fundamental experiential states: presence and absence. Presence was defined as self-regulated attention to present-moment experience, which is the first component of mindfulness. Absence was defined as a lack of such attention, encompassed by the state of mindlessness or dearth of mindful awareness to the moment. Guided by Polyvagal Theory (PVT), the study hypothesized that these two states would be associated with distinct patterns of autonomic activity across cardiac and respiratory domains. A repeated single-case design was employed with five participants over 20 days using ecological momentary assessment and ambulatory physiological monitoring. Participants provided reports of presence or absence in response to smartphone prompts, which were temporally linked to physiological data collected via wearable sensors. Measures included heart rate (HR), heart rate variability (as indexed by RMSSD), respiratory rate, and tidal volume. A movement-based meditation, hypothesized to foster embodied presence, was practiced for 10 days. Analyses focused on within-person patterns using permutation-based approaches, with physiological variables standardized relative to each individual’s baseline. Results demonstrated both increases and decreases in reports of presence across the study. Physiologically, two sets of patterns for presence and absence emerged, providing preliminary evidence that presence and absence may be associated with identifiable autonomic signatures. One pattern was primarily characterized by cardiac indicators (lower HR and higher RMSSD during absence), and another by respiratory patterns (higher respiratory rate during absence). These findings provided partial support for the hypothesized distinction between presence and absence, while also suggesting that individual differences may drive patterns of autonomic correlates. While PVT provides a useful organizing framework, incorporating self-reports of arousal may be necessary for a more complete account of the physiological organization of momentary conscious experience in naturalistic contexts. Importantly, the within-person frame of reference used in this exploratory pilot study highlighted a potential limitation of the predominant between-person approach, in that aggregating data across the five participants obscured the meaningful individual patterns of physiological activity that were discovered. The findings suggest that idiographic and ecologically valid methodologies are useful for advancing the understanding of mind - body relationships in naturalistic settings.