Neuroimage
July 12, 2017
Candace R. Lewis, Katrin H. Preller, Rainer Kraehenmann et al.
105 citations
Psilocybin, the active compound in psychedelic mushrooms, is an agonist of various serotonin receptors. Seminal psilocybin positron emission tomography (PET) research suggested regional increases in glucose metabolism in frontal cortex (hyperfrontality). However, a recent arterial spin labeling (ASL) study suggests psilocybin may lead to hypo-perfusion in various brain regions. In this...
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...
Psychopharmacology
July 1, 2017
Rainer Kraehenmann, Dan Pokorný, Leonie Vollenweider et al.
Rationale Accumulating evidence indicates that the mixed serotonin and dopamine receptor agonist lysergic acid diethylamide (LSD) induces an altered state of consciousness that resembles dreaming. Objectives This study aimed to test the hypotheses that LSD produces dreamlike waking imagery and that this imagery depends on 5-HT2A receptor activation and is related to subjective drug effects....
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...
Proceedings of the National Academy of Sciences
April 18, 2016
Katrin H. Preller, Thomas Pokorny, Andreas Hock et al.
175 citations
Social ties are crucial for physical and mental health. However, psychiatric patients frequently encounter social rejection. Moreover, an increased reactivity to social exclusion influences the development, progression, and treatment of various psychiatric disorders. Nevertheless, the neuromodulatory substrates of rejection experiences are largely unknown. The preferential serotonin (5-HT)...
European Neuropsychopharmacology
January 22, 2016
Thomas Pokorny, Katrin H. Preller, Rainer Kraehenmann et al.
148 citations
The mixed serotonin (5-HT) 1A/2A/2B/2C/6/7 receptor agonist psilocybin dose-dependently induces an altered state of consciousness (ASC) that is characterized by changes in sensory perception, mood, thought, and the sense of self. The psychological effects of psilocybin are primarily mediated by 5-HT2A receptor activation. However, accumulating evidence suggests that 5-HT1A or an interaction...
Current Topics in Behavioral Neurosciences
2016
Katrin H. Preller, Franz X. Vollenweider
285 citations
Classic serotonergic hallucinogens or psychedelics produce an altered states of consciousness (ASC) that is characterized by profound alterations in sensory perception, mood, thought including the perception of reality, and the sense of self. Over the past years, there has been considerable progress in the search for invariant and common features of psychedelic states. In the first part of this...
NeuroImage Clinical
August 22, 2015
Rainer Kraehenmann, André Schmidt, Karl Friston et al.
107 citations
Stimulation of serotonergic neurotransmission by psilocybin has been shown to shift emotional biases away from negative towards positive stimuli. We have recently shown that reduced amygdala activity during threat processing might underlie psilocybin's effect on emotional processing. However, it is still not known whether psilocybin modulates bottom-up or top-down connectivity within the...
European Psychiatry
March 1, 2015
Katrin H. Preller, Thomas Pokorny, Rainer Krähenmann et al.
20 citations
Social cognition is a crucial factor influencing development, progress, and treatment of psychiatric disorders. However, social cognition skills are insufficiently targeted by current treatment approaches. In particular, patients suffering from depression show an increased negative reaction to social exclusion and deficits in empathy. The 5HT-1A/2A receptor agonist psilocybin has previously...
Biological Psychiatry
November 29, 2014
Yasmin Schmid, Florian Enzler, Peter Gasser et al.
425 citations
BackgroundAfter no research in humans for >40 years, there is renewed interest in using lysergic acid diethylamide (LSD) in clinical psychiatric research and practice. There are no modern studies on the subjective and autonomic effects of LSD, and its endocrine effects are unknown. In animals, LSD disrupts prepulse inhibition (PPI) of the acoustic startle response, and patients with...
Biological Psychiatry
April 26, 2014
Rainer Kraehenmann, Katrin H. Preller, Milan Scheidegger et al.
325 citations
BackgroundThe amygdala is a key structure in serotonergic emotion-processing circuits. In healthy volunteers, acute administration of the serotonin 1A/2A/2C receptor agonist psilocybin reduces neural responses to negative stimuli and induces mood changes toward positive states. However, it is little-known whether psilocybin reduces amygdala reactivity to negative stimuli and whether any change...
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...
PLoS One
August 31, 2010
Erich Studerus, Alex Gamma, Franz X. Vollenweider
693 citations
The original scales of the OAV were shown to be multidimensional constructs. Eleven new lower order scales were constructed and demonstrated to have desirable psychometric properties. The new lower order scales are most likely better suited to assess drug induced ASC.
Emergency Medicine Journal
April 8, 2010
Cédric M. Hysek, Franz X. Vollenweider, Matthias E. Liechti
50 citations
The results of this study indicate that beta-blockers may prevent increases in heart rate but not hypertensive and adverse effects of MDMA.
Journal of Vision
March 19, 2010
Olivia Carter, John D. Pettigrew, Felix Hasler et al.
3 citations
Binocular rivalry refers to the fluctuations in visual awareness/suppression that occur when different images are simultaneously presented to each eye. To explore the role of serotonin (5-HT) in binocular rivalry, this study investigated the affects of the hallucinogenic 5-HT1A&2A receptor agonist psilocybin (the active compound in “magic mushrooms”), alone and after pretreatment with the...
Journal of Vision
March 17, 2010
Olivia Carter, David C. Burr, John D. Pettigrew et al.
6 citations
Increasing evidence suggests a link between attention, working memory, serotonin (5-HT) and prefrontal cortex activity. In an attempt to tease out the relationship between these elements, this study tested the effects of the hallucinogenic 5-HT1A/2A receptor agonist psilocybin alone and after pretreatment with the 5-HT2A antagonist ketanserin on multiple object tracking and spatial working...