23 papers in the library · 3,246 citations · publishing 2010-2024
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...
Scientific Reports October 24, 2019 Lukasz Smigielski, Michael Kometer, Milan Scheidegger et al. 174 citations
Meditation and psychedelics have played key roles in humankind's search for self-transcendence and personal change. However, neither their possible synergistic effects, nor related state and trait predictors have been experimentally studied. To elucidate these issues, we administered double-blind the model psychedelic drug psilocybin (315 μg/kg PO) or placebo to meditators (n = 39) during a...
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...
Current Topics in Behavioral Neurosciences 2018 Michael Kometer, Franz X. Vollenweider
Serotonergic hallucinogens, such as lysergic acid diethylamide (LSD), psilocybin, and N,N-dimethyltryptamine (DMT), are famous for their capacity to temporally and profoundly alter an individual's visual experiences. These visual alterations show consistent attributes despite large inter- and intra-individual variances. Many reports document a common perception of colors as more saturated, with...
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...
Neuropsychopharmacology March 2012 André Schmidt, Rosilla Bachmann, Michael Kometer et al.
Psychotomimetics like the N-methyl-D-aspartate receptor (NMDAR) antagonist ketamine and the 5-hydroxytryptamine2A receptor (5-HT(2A)R) agonist psilocybin induce psychotic symptoms in healthy volunteers that resemble those of schizophrenia. Recent theories of psychosis posit that aberrant encoding of prediction errors (PE) may underlie the expression of psychotic symptoms. This study used a...
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...