Scientific Reports
April 23, 2024
Berit Singer, Daniel Meling, Matthias Hirsch-Hoffmann et al.
The original version of this Article contained an error in the name of author Berit Singer which was incorrectly given as Singer Berit.
Scientific Reports
March 26, 2024
Berit Singer, Daniel Meling, Matthias Hirsch-Hoffmann et al.
15 citations
In this study, for the first time, we explored a dataset of functional magnetic resonance images collected during focused attention and open monitoring meditation before and after a five-day psilocybin-assisted meditation retreat using a recently established approach, based on the Mapper algorithm from topological data analysis. After generating subject-specific maps for two groups (psilocybin...
Frontiers in Pharmacology
2023
Dario Dornbierer, Laurenz Marten, Jovin Mueller et al.
32 citations
Recently, the Amazonian plant medicine "ayahuasca"-containing the psychedelic compound N,N-dimethyltryptamine (DMT) and numerous β-carboline alkaloids, such as harmine-has been suggested to exhibit beneficial effects in patients with affective and other mental health disorders. Although ayahuasca ingestion is considered safe, its pharmacokinetics/pharmacodynamics and tolerability profile pose...
Human Brain Mapping
August 21, 2020
Lukasz Smigielski, Michael Kometer, Milan Scheidegger et al.
42 citations
Abstract The concept of self and self‐referential processing has a growing explanatory value in psychiatry and neuroscience, referring to the cognitive organization and perceptual differentiation of self‐stimuli in health and disease. Conditions in which selfhood loses its natural coherence offer a unique opportunity for elucidating the mechanisms underlying self‐disturbances. We assessed the...
Schizophrenia Bulletin
August 5, 2020
Pantelis Leptourgos, Martin Fortier-Davy, Robin Carhart-Harris et al.
88 citations
Abstract The recent renaissance of psychedelic science has reignited interest in the similarity of drug-induced experiences to those more commonly observed in psychiatric contexts such as the schizophrenia-spectrum. This report from a multidisciplinary working group of the International Consortium on Hallucinations Research (ICHR) addresses this issue, putting special emphasis on hallucinatory...
Journal of Neuroscience
June 19, 2020
Lilian Weber, Andreea O. Diaconescu, Christoph Mathys et al.
82 citations
The auditory mismatch negativity (MMN) is significantly reduced in schizophrenia. Notably, a similar MMN reduction can be achieved with NMDA receptor (NMDAR) antagonists. Both phenomena have been interpreted as reflecting an impairment of predictive coding or, more generally, the "Bayesian brain" notion that the brain continuously updates a hierarchical model to infer the causes of its sensory...
Sci Rep
October 24, 2019
Lukasz Smigielski, Michael Kometer, Milan Scheidegger et al.
174 citations
Characterization and prediction of acute and sustained response to psychedelic psilocybin in a mindfulness group retreat.
Neuroimage
August 1, 2019
Lukasz Smigielski, Milan Scheidegger, Michael Kometer et al.
261 citations
Both psychedelics and meditation exert profound modulatory effects on consciousness, perception and cognition, but their combined, possibly synergistic effects on neurobiology are unknown. Accordingly, we conducted a randomized, double-blind, placebo-controlled study with 38 participants following a single administration of the psychedelic psilocybin (315 μg/kg p.o.) during a 5-day mindfulness...
Psychopharmacology
July 1, 2017
Robin Rotz, Michael Kometer, Dario Dornbierer et al.
19 citations
Rationale Gamma-hydroxybutyrate (GHB) is a putative neurotransmitter, a drug of abuse, an anesthetic agent, and a treatment for neuropsychiatric disorders. In previous electroencephalography (EEG) studies, GHB was shown to induce an electrophysiological pattern of “paradoxical EEG-behavioral dissociation” characterized by increased delta and theta oscillations usually associated with sleep...
The International Journal of Neuropsychopharmacology
June 14, 2017
Thomas Pokorny, Katrin H. Preller, Michael Kometer et al.
202 citations
Background: Impaired empathic abilities lead to severe negative social consequences and influence the development and treatment of several psychiatric disorders. Furthermore, empathy has been shown to play a crucial role in moral and prosocial behavior. Although the serotonin system has been implicated in modulating empathy and moral behavior, the relative contribution of the various serotonin...
Psychopharmacology
July 31, 2015
Michael Kometer, Thomas Pokorny, Erich Seifritz et al.
165 citations
RationaleDuring the last years, considerable progress has been made toward understanding the neuronal basis of consciousness by using sophisticated behavioral tasks, brain-imaging techniques, and various psychoactive drugs. Nevertheless, the neuronal mechanisms underlying some of the most intriguing states of consciousness, including spiritual experiences, remain unknown.ObjectivesTo elucidate...
Cerebral Cortex
July 16, 2013
Fosco Bernasconi, André Schmidt, Thomas Pokorny et al.
62 citations
Emotional face processing is critically modulated by the serotonergic system. For instance, emotional face processing is impaired by acute psilocybin administration, a serotonin (5-HT) 1A and 2A receptor agonist. However, the spatiotemporal brain mechanisms underlying these modulations are poorly understood. Here, we investigated the spatiotemporal brain dynamics underlying psilocybin-induced...
Journal of Neuroscience
June 19, 2013
Michael Kometer, André Schmidt, Lutz Jäncke et al.
357 citations
Visual illusions and hallucinations are hallmarks of serotonergic hallucinogen-induced altered states of consciousness. Although the serotonergic hallucinogen psilocybin activates multiple serotonin (5-HT) receptors, recent evidence suggests that activation of 5-HT2A receptors may lead to the formation of visual hallucinations by increasing cortical excitability and altering visual-evoked...
Cerebral Cortex
August 8, 2012
André Schmidt, Andreea O. Diaconescu, Michael Kometer et al.
110 citations
This paper presents a model-based investigation of mechanisms underlying the reduction of mismatch negativity (MMN) amplitudes under the NMDA-receptor antagonist ketamine. We applied dynamic causal modeling and Bayesian model selection to data from a recent ketamine study of the roving MMN paradigm, using a cross-over, double-blind, placebo-controlled design. Our modeling was guided by a...
Psychopharmacology
July 26, 2012
André Schmidt, Michael Kometer, Rosilla Bachmann et al.
94 citations
RationaleBoth glutamate and serotonin (5-HT) play a key role in the pathophysiology of emotional biases. Recent studies indicate that the glutamate N-methyl-D-aspartate (NMDA) receptor antagonist ketamine and the 5-HT receptor agonist psilocybin are implicated in emotion processing. However, as yet, no study has systematically compared their contribution to emotional biases.ObjectivesThis study...
Biological Psychiatry
May 9, 2012
Michael Kometer, André Schmidt, Rosilla Bachmann et al.
300 citations
BackgroundSerotonin (5-HT) 1A and 2A receptors have been associated with dysfunctional emotional processing biases in mood disorders. These receptors further predominantly mediate the subjective and behavioral effects of psilocybin and might be important for its recently suggested antidepressive effects. However, the effect of psilocybin on emotional processing biases and the specific...
PLoS One
February 17, 2012
Erich Studerus, Alex Gamma, Michael Kometer et al.
372 citations
Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24...
Neuropsychopharmacology
September 28, 2011
Boris B. Quednow, Michael Kometer, Mark A. Geyer et al.
241 citations
The serotonin-2A receptor (5-HT(2A)R) has been implicated in the pathogenesis of schizophrenia and related inhibitory gating and behavioral inhibition deficits of schizophrenia patients. The hallucinogen psilocybin disrupts automatic forms of sensorimotor gating and response inhibition in humans, but it is unclear so far whether the 5-HT(2A)R or 5-HT(1A)R agonist properties of its bioactive...
Biological Psychiatry
December 4, 2010
Michael Kometer, B. Rael Cahn, David Andel et al.
101 citations
BackgroundRecent findings suggest that the serotonergic system and particularly the 5-HT2A/1A receptors are implicated in visual processing and possibly the pathophysiology of visual disturbances including hallucinations in schizophrenia and Parkinson's disease.MethodsTo investigate the role of 5-HT2A/1A receptors in visual processing the effect of the hallucinogenic 5-HT2A/1A agonist...
Journal of Psychopharmacology
September 20, 2010
Erich Studerus, Michael Kometer, Felix Hasler et al.
529 citations
Psilocybin and related hallucinogenic compounds are increasingly used in human research. However, due to limited information about potential subjective side effects, the controlled medical use of these compounds has remained controversial. We therefore analysed acute, short- and long-term subjective effects of psilocybin in healthy humans by pooling raw data from eight double-blind...
Nature reviews. Neuroscience
September 2010
Franz X Vollenweider, Michael Kometer
After a pause of nearly 40 years in research into the effects of psychedelic drugs, recent advances in our understanding of the neurobiology of psychedelics, such as lysergic acid diethylamide (LSD), psilocybin and ketamine have led to renewed interest in the clinical potential of psychedelics in the treatment of various psychiatric disorders. Recent behavioural and neuroimaging data show that...