Major Depressive Disorder (MDD)Depressive DisordersPsilocybin

Psilocybin-assisted therapy of major depressive disorder using Acceptance and Commitment Therapy as a therapeutic frame

This theory-building paper (2020) argues for the synergy between Acceptance and Commitment Therapy (ACT) and psilocybin-assisted therapy, describes the process, and limitations to using this framework.

Authors

  • James Guss
  • Thomas Williams
  • Monnica Williams

Published

Journal of Contextual Behavioral Science
meta Study

Abstract

Psychedelic-assisted therapy is based on the premise that psychedelic substances can act as catalysts or adjuncts to psychotherapeutic processes. Recent clinical trials involving psychedelic-assisted therapy have generally employed a similar three-part structure consisting of preparation, support during the dosing sessions, and subsequent “integration.” However, the content of these sessions and the frame through which the therapists approach participants and understand the clinical process has thus far been inconsistent among studies. In designing a manualized therapy protocol for a small clinical trial of psilocybin-assisted therapy for major depressive disorder, our group sought to delineate an explicit and replicable, evidence-based model that intentionally builds upon both the neurobiological actions of the medication and the phenomenology of the drug experience. Having identified considerable concordance in proposed mechanisms of change between Acceptance and Commitment Therapy (ACT) and psilocybin therapy, we employed ACT as an overarching psychotherapeutic framework. We hypothesize that the psilocybin experience can provide direct experiential contact with ACT processes that increase psychological flexibility, and that these deeply felt experiences may in turn be reinforced during ACT-informed follow-up therapy sessions. In this paper, we describe the rationale for selecting ACT, areas of potential synergism between ACT and psilocybin-therapy, the basic structure of our treatment model, and limitations to this approach.

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Research Summary of 'Psilocybin-assisted therapy of major depressive disorder using Acceptance and Commitment Therapy as a therapeutic frame'

Introduction

Classical psychedelics such as psilocybin produce marked alterations in cognition, perception and emotion via serotonin 5HT-2A receptor agonism. After a long hiatus in research following regulatory restrictions in the 1970s, interest in psychedelic-assisted therapies has resurged, with recent clinical trials typically organised around a three-part structure of preparatory sessions, supported dosing sessions, and integration work afterwards. However, the content and therapeutic framing of preparation and integration have varied markedly between studies: some trials use non-specific supportive models while others incorporate elements of condition-specific, evidence-based therapies. This heterogeneity leaves open questions about how best to harness the subjective, set-and-setting-dependent aspects of the psychedelic experience to produce durable clinical change in specific disorders such as major depressive disorder (MDD). Sloshower and colleagues set out to develop a manualised, replicable model for psilocybin-assisted therapy tailored to MDD by intentionally aligning psychotherapeutic procedures with both the neurobiological effects of psilocybin and the phenomenology of the drug experience. After evaluating candidate modalities, the study team selected Acceptance and Commitment Therapy (ACT) as the overarching therapeutic frame. They hypothesise that moderate-to-high dose psilocybin can provide direct experiential contact with ACT processes that increase psychological flexibility and that ACT-informed preparatory and integration sessions can reinforce those experiences to extend clinical benefit. The paper describes the rationale for selecting ACT, the points of conceptual overlap with psilocybin therapy, the basic structure of the manual, therapist training, and acknowledged limitations of the approach.

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Study Details

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