Acceptance as a possible link between past psychedelic experiences and psychological flexibility

Introduction

Classical psychedelics such as psilocybin, LSD, DMT and mescaline have been linked to lasting improvements in mental health and well-being, and recent research highlights the importance of acute psychologically transformative experiences—mystical-type phenomena and psychological insights—as predictors of improved outcomes in psychedelic-assisted therapy. Psychological flexibility (PF), a multidimensional construct encompassing six adaptive components (Acceptance, Defusion, Present Moment Awareness, Self-as-Context, Values clarification, Committed Action) and its counterpart psychological inflexibility (PI) with six maladaptive components, has been proposed as one mechanism that could underlie sustained benefits after psychedelic use. Prior work has tended to treat PF as a unidimensional construct (often via the AAQ-II), which overlooks the distinct but interrelated components that may differentially relate to psychedelic experiences and mental health. This study, led by Krabbe and colleagues, set out to examine how features of a single meaningful past psychedelic experience (mystical-type features and psychological insight) and measures of past use frequency relate to current, component-level PF and PI, and to well-being and ill-being. The investigators used two complementary analytic strategies: network analysis to map associations among components and outcomes (an “Acute Model” using experience measures and a “Frequency Model” using use-frequency measures), and mediation analyses to test whether aggregate psychological flexibility mediates relationships between past psychedelic variables and present well-being/ill-being. The approach aims to clarify whether the quality (depth) or quantity (frequency) of past psychedelic use more strongly relates to multidimensional PF and mental health.