Neuroscience of Consciousness
January 1, 2017
Chris Letheby, Philip Gerrans
280 citations
Psychedelic-induced ego dissolution—where the sense of being a distinct self disappears—is best explained by predictive processing models of self-awareness. Self-awareness arises from hierarchical predictive models that posit a stable, enduring entity to which representations are bound. The self-model functions as a useful Cartesian fiction: a false representation of a simple substance that integrates cognitive processing across levels and domains. Unlike narrative accounts, this self-model has a robust cognitive function, but it does not qualify as a real self. Ego dissolution reveals the self-model's binding role in cognition, yet the self itself does not exist.
September 13, 2024
Chris Letheby, Philip Gerrans
6 citations
A recent wave of research re-examines classic psychedelic substances such as psilocybin, LSD, and DMT. Evidence suggests these can be given safely in controlled conditions at moderate to high doses and may help treat addictive and mood disorders. The main mechanism appears to be inducing a dramatically altered state of consciousness, but how psychedelic-assisted psychotherapy works and the relations between subjective experiences and neural changes are debated. This volume collects philosophical chapters on three themes: what psychedelic science reveals about self and mind; methodological, theoretical, and clinical questions about studying and using psychedelics therapeutically; and broader ethical, spiritual, and cultural implications of psychedelic experience.
Philosophical Perspectives on Psychedelic Psychiatry
September 13, 2024
Chris Letheby, Philip Gerrans
1 citation
This chapter reviews the history of psychedelics in psychiatry, including the phenomenological and behavioral effects that initially prompted their therapeutic study. It provides an overview of recent research on the safety, efficacy, and therapeutic mechanisms of psychedelic-assisted psychotherapy. The chapter also summarizes the contributions of each chapter in the volume, showing how they address philosophical issues arising from the new wave of psychedelic psychiatry. The chapters are organized around three themes: 'Self and Mind', 'Science and Psychiatry', and 'Ethics and Spirituality'.
Philip Gerrans, Hugh Mgovern, Jakob Hohwy et al.
1 citation
preprint
Complex post-traumatic stress disorder (C-PTSD) involves additional symptoms beyond those of PTSD, including emotional instability, negative self-concept, and interpersonal difficulties, often from prolonged trauma like childhood maltreatment or domestic violence. A novel model based on active inference and self-modelling explains these differences and identifies the insula's role in affective regulation. The model suggests that MDMA-assisted therapy may help recalibrate emotional regulation and strengthen self-model, offering a potential treatment avenue. Theoretical and clinical implications are discussed, with emphasis on further empirical research.
European journal of psychotraumatology
December 1, 2026
Philip Gerrans, Hugh McGovern, Jakob Hohwy et al.
Complex post-traumatic stress disorder (C-PTSD) involves lasting difficulties with emotions, self-concept, and relationships, beyond typical PTSD symptoms. This review proposes a neurocognitive explanation based on predictive processing and self-modelling, focusing on how the brain's insula integrates bodily signals, emotions, and self-awareness. The authors suggest that C-PTSD arises from maladaptive predictions shaped by prolonged interpersonal trauma, leading to unstable self-regulation. They examine MDMA-assisted psychotherapy as one intervention that may temporarily alter emotional salience, trust, and self-related thinking. The framework generates testable hypotheses about self-modelling in C-PTSD and offers guidance for developing treatments that target affective regulation and self-referential processing.