Psilocybin is a naturally occurring classic psychedelic associated with widespread changes in brain function and promising therapeutic outcomes in several neuropsychiatric disorders. Complementing these findings, qualitative studies following psilocybin administration have revealed diverse and highly individual effects across multiple domains of subjective experience. However, little is known...
BACKGROUND: Psychedelics exert widespread effects on brain activity, but their impact on motor function is unclear. This is clinically relevant given the emerging interest in psychedelic-assisted physical therapy for disorders of motor function. This study examined the feasibility and safety of administering movement tasks following low-to-moderate doses of psilocybin in healthy volunteers....
RATIONALE: Clinical interest in psilocybin-assisted rehabilitation for motor disorders is growing. However, psilocybin's motor effects are under-researched, and quantifying them is essential for assessing treatment risks and outcomes. OBJECTIVES: This study aims to clarify whether acute effects of psilocybin disrupt established patterns of manual dexterity and coordination. Specifically, we...
Despite growing interest in the therapeutic potential of 3,4-methylenedioxymethamphetamine (MDMA), no targeted measure to systematically assess side effects of MDMA-assisted psychotherapy (MDMA-AP) exists. Our aim was to develop an MDMA-Assisted Psychotherapy Side Effects Tool (M-SET) to capture side effects over the course of MDMA-AP. Informed by a systematic review and a review of other...
Background Psilocybin is a classic psychedelic that acutely alters brain functional connectivity. These changes are linked to therapeutic doses and subjective effects, with some evidence that changes persist beyond acute drug administration. However, the effects of lower doses on sustained connectivity changes remain unclear.
Functional disorders, characterised by symptoms unexplained by organic disease, impose a significant burden on individuals and healthcare systems. Existing treatments are limited in efficacy, with no effective pharmacotherapies. There is growing evidence supporting the treatment potential of psychedelics in neuropsychiatric conditions, including several distinct functional disorders. This...
Conscious experience depends on the coordinated activity of neural processes that span multiple scales: from synapses to whole-brain dynamics. A recently introduced measure, dynamical independence (DI), identifies, characterises, and quantifies these multi-scale relationships using an information-theoretic dimensionality reduction approach. Here, we use DI to examine changes in the emergent...
Abstract Background Psychedelics exert widespread effects on brain activity, but their impact on motor function is unclear. This is clinically relevant given the emerging interest in psychedelic-assisted physical therapy for disorders of motor function. This study’s primary objectives examined the feasibility and safety of administering movement tasks following low-to-moderate doses of...
Abstract Background: Motor functional neurological disorder (FND) is a common illness associated with significant functional impairment. There are no effective pharmacotherapies, and despite the early promise of physiotherapy studies, many suffer disabling symptoms in the long term. There is a theoretical rationale for combining psychedelics with physiotherapy; however, the potential benefit of...
The most well known study on doing nothing concluded that being alone for 15 mins with nothing to do but think is aversive. Here we examine skilful doing nothing in the form of Stillness Meditation. Meditation-naive adult participants (N = 165) were randomly allocated to 15 mins of Stillness Meditation or one of two active controls (Focused Attention and Audiobook). Stillness Meditation...
Background: Depressive disorders are a major global health challenge, with many individuals unresponsive to existing treatments. Novel psychedelic therapies show promise but require further research. Objectives: This study aimed to evaluate the feasibility, safety and effectiveness of psilocybin with psychotherapeutic support for treatment-resistant depression (TRD), investigate predictors of...
Abstract Background Depressive disorders are a major global health challenge, with many individuals unresponsive to existing treatments or left with residual symptoms such as impairments in cognition and social functioning. Emerging psychedelic therapies show promise for treating depression but require further research. Aims & Objectives This pilot study aimed to evaluate the feasibility,...
Conscious experience depends on the coordinated activity of neural processes that span multiple scales—from synapses to whole-brain dynamics. A recently introduced measure, dynamical independence, identifies, characterises and quantifies these multi-scale relationships using an information-theoretic dimensionality-reduction approach. Here, we use DI to examine changes in emergent dynamical...
This article presents a taxonomy of altered states of consciousness, primarily based on their central phenomenological features. Following taxonomic principles and a modified Delphi methodology, a multidisciplinary, international group identified eight distinct phenomenological/behavioral states (some with subcategories): proto and transitional, delirium, minimal to no awareness, experiential...
Background There has been a resurgence of research into the potential therapeutic benefits of psychedelics for neuropsychiatric disorders. Classic psychedelics, such as psilocybin, exert complex effects on higher cognitive functions such as perception and awareness, but their impact on motor function remains unexplored. Moreover, there is a theoretical rationale for using psychedelics to...
Abstract Evidence suggests that MDMA-assisted psychotherapy (MDMA-AP) has therapeutic potential for treatment of psychiatric illness. We conducted the first comprehensive systematic review and meta-analysis of the side effects of MDMA-AP across indications. We also assessed the quality of side effects-reporting in published trials of MDMA-AP. PubMed, EMBASE, PsycINFO, MEDLINE and Cochrane...
Abstract Objectives Contentless experience involves an absence of mental content such as thoughts and perceptions. It is often described as pure consciousness or complete stillness/silence, and is a goal in Shamatha, Thai Forest, and Stillness Meditation. This study examined the subjective character of the deepest experience of stillness/silence typically reported in each practice, and whether...
Abstract In contentless experience (sometimes termed pure consciousness ) there is an absence of mental content such as thought, perception, and mental imagery. The path to contentless experience in meditation can be taken to comprise the meditation technique, and the experiences (“interim-states”) on the way to the contentless “goal-state/s”. Shamatha, Transcendental, and Stillness Meditation...
Abstract Contentless experience involves an absence of mental content such as thought, perception, and mental imagery. In academic work it has been classically treated as including states like those aimed for in Shamatha, Transcendental, and Stillness Meditation. We have used evidence synthesis to select and review 135 expert texts from within the three traditions. In this paper we identify the...
The medical use of psychedelic substances (e.g. psilocybin, ayahuasca, lysergic acid diethylamide and 3,4-methylenedioxymethamphetamine) is attracting renewed interest, driven by a pressing need for research and development of novel therapies for psychiatric disorders, as well as promising results of contemporary studies. In this Viewpoint, we reflect upon the ‘Clinical Memorandum on...
Recent theories in computational psychiatry propose that unusual perceptual experiences and delusional beliefs may emerge as a consequence of aberrant inference and disruptions in sensory learning. The current study investigates these theories and examines the alterations that are specific to schizophrenia spectrum disorders vs those that occur as psychotic phenomena intensify, regardless of...
Shamatha, Transcendental, and Stillness Meditation are said to aim for "contentless" experiences, where mental content such as thoughts, perceptions, and mental images is absent. Silence is understood to be a central feature of those experiences. The main source of information about the experiences is texts by experts from within the three traditions. Previous research has tended not to use an...
Abstract This review in memoriam of Jack Pettigrew provides an overview of past and current research into the phenomenon of multistable perception across multiple animal species. Multistable perception is characterized by two or more perceptual interpretations spontaneously alternating, or rivaling, when animals are exposed to stimuli with inherent sensory ambiguity. There is a wide array of...
In their Review “What is consciousness, and could machines have it?” (27 October 2017, p. [486][1]), S. Dehaene et al. argue that the science of consciousness indicates that we are not on the verge of creating conscious machines. However, Dehaene et al. ask and answer the wrong questions. To
It has often been suggested in the popular and academic literature that the psychedelic state qualifies as a higher state of consciousness relative to the state of normal waking awareness. This article subjects this proposal to critical scrutiny, focusing on the question of what it would mean for a state of consciousness to be 'higher'. We begin by considering the contrast between conscious...