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Self-Entropic Broadening Theory: Toward a New Understanding of Self and Behavior Change Informed by Psychedelics and Psychosis

This review (2022) provides a theory of how changes due to (classical) psychedelics and psychosis have such different (positive vs negative) outcomes. This is done through the lens of self-entropic broadening theory (broader attentional scope, hyperassociative thinking), where psychedelics lead to low self-focus (awe, ego dissolution, mystical experiences), whilst psychosis leads to high self-focus (hyperreflexivity, self-referential processing).

Authors

  • Peter Hendricks

Published

Pharmacological Reviews
meta Study

Abstract

The extremes of human experiences, such as those occasioned by classic psychedelics and psychosis, provide a rich contrast for understanding how components of these experiences impact well-being. In recent years, research has suggested that classic psychedelics display the potential to promote positive enduring psychologic and behavioral changes in clinical and nonclinical populations. Paradoxically, classic psychedelics have been described as psychotomimetics. This review offers a putative solution to this paradox by providing a theory of how classic psychedelics often facilitate persistent increases in well-being, whereas psychosis leads down a “darker” path. This will be done by providing an overview of the overlap between the states (i.e., entropic processing) and their core differences (i.e., self-focus). In brief, entropic processing can be defined as an enhanced overall attentional scope and decreased predictability in processing stimuli facilitating a hyperassociative style of thinking. However, the outcomes of entropic states vary depending on level of self-focus, or the degree to which the associations and information being processed are evaluated in a self-referential manner. We also describe potential points of overlap with less extreme experiences, such as creative thinking and positive emotion-induction. Self-entropic broadening theory offers a heuristically valuable perspective on classic psychedelics and their lasting effects and relation to other states by creating a novel synthesis of contemporary theories in psychology.

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Research Summary of 'Self-Entropic Broadening Theory: Toward a New Understanding of Self and Behavior Change Informed by Psychedelics and Psychosis'

Introduction

Classic psychedelic-assisted therapy has attracted growing attention because trials and population-level analyses suggest these substances can produce enduring psychological and behavioural benefits across diverse conditions, including substance use disorders, depression, end-of-life anxiety, and demoralisation. At a biological level, research indicates classic psychedelics promote neuroplasticity and have anti-inflammatory effects, offering plausible mechanisms for lasting change. Paradoxically, these same compounds have a long history of being described as psychotomimetic; early investigators proposed using psychedelics to model psychosis "from the inside," and subsequent empirical work has noted acute overlaps between psychedelic states and features of early psychosis. Dourron and colleagues set out to resolve this psychotomimetic–psychedelic paradox by proposing self-entropic broadening (SEB) theory. SEB synthesises existing frameworks—notably entropic brain theory (EBT), REBUS, and broaden-and-build theory—by arguing that both classic psychedelics and early psychosis instantiate an entropic processing style (broadened attentional scope, decreased predictability and hyperassociative thinking), but diverge in the degree and direction of self-focus. The review aims to characterise shared cognitive and neural features, specify where and why trajectories differ, and suggest testable predictions and research priorities to explain when entropic states lead to flourishing versus languishing.

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References (132)

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