When people experience a near-death or life-threatening incident, they sometimes report an altered state of consciousness in which they have the perception of being out of or away from their physical body. During such an experience these individuals at times have the impression of encountering a spiritual personage who offers them a choice to stay or return to their physical life and/or...
Since its synthesis in 1962, ketamine has been widely used in diverse medical contexts, from anesthesia to treatment-resistant depression. However, interpretations of ketamine's subjective effects remain polarized. Biomedical frameworks typically construe the drug's experiential effects as dissociative or psychotomimetic, while psychedelic paradigms emphasize the potential therapeutic merits of...
To determine the relationships between psilocybin dose, psychedelic experiences, and therapeutic outcome in treatment-resistant depression. For treatment-resistant depression, 233 participants received a single dose of 25, 10, or 1 mg of COMP360 psilocybin (a proprietary, pharmaceutical-grade synthesized psilocybin formulation, developed by the sponsor, Compass Pathfinder Ltd.) with...
The Hallucinogen Rating Scale (HRS) has been widely used to measure the subjective effects of psychedelics and other psychoactive substances. Its advantages include a basis in phenomenological interviews and clinical studies, straightforward items, and broad coverage of psychedelic effects. Previous studies have attempted to resolve its factor structure but were limited by small samples of...
Background: This study investigates the complex relationship between accentuation and attention in visual perception, extending classical Gestalt principles by introducing dissimilarity as a complementary mechanism to similarity in perceptual organization. Objectives and Methods: Through a series of phenomenological experiments, we demonstrate how accentuation, driven by dissimilarity, plays a...
Stroboscopic light stimulation (SLS) on closed eyes typically induces simple visual hallucinations (VHs), characterised by vivid, geometric and colourful patterns. A dataset of 862 sentences, extracted from 422 open subjective reports, was recently compiled as part of the Dreamachine programme (Collective Act, 2022), an immersive multisensory experience that combines SLS and spatial sound in a...
THE ELEPHANT AND THE BLIND: The Experience of Pure Consciousness--Philosophy, Science, and 500+ Experiential Reports by Thomas Metzinger. MIT Press, 2024. 648 pages. Paperback; $80.00. ISBN: 9780262547109. *What is consciousness and how can science fruitfully study it? In this book, Thomas Metzinger proposes that the experience of pure awareness occurs without "subjectivity" and will help...
Cette étude explore comment les expériences de mort imminente (EMI) transforment la perception du Réel. Elle introduit la « conscience EMISTE », un état modifié de conscience. Les concepts de « corps phénoménal » et d’« ultra-réel » sont mis en avant, avec des perceptions intensifiées, les « ultra qualia ». Cette recherche propose de réévaluer la nature du Réel et de la conscience, en ouvrant...
Psychedelics are well known for their ability to produce profoundly altered states of consciousness. But, more importantly, the effects of psychedelics can influence neurobehavioral changes that last well after these acute subjective effects end. This phenomenon is currently being leveraged in the development of psychedelic-assisted psychotherapies for the treatment of multiple neuropsychiatric...
In a recent set of articles (Klein et al., 2023; Klein & Loftus, 2024), my colleagues and I used the logic of adaptationism—the application of evolutionary principles to study the functional design of naturally selected systems (e.g., Klein et al., 2002)—to help make sense of the role natural selection played in the evolution of consciousness. To avoid well-known, seemingly intractable problems...