Biological Psychiatry
April 26, 2014
Rainer Kraehenmann, Katrin H. Preller, Milan Scheidegger et al.
325 citations
Psilocybin significantly reduced anxiety and depression symptoms in 67% of participants after just one treatment session. Utilizing functional magnetic resonance imaging, the study revealed heightened activity in the amygdala, indicating a strong serotonergic influence on emotional processing. Participants reported improved mood and cognitive flexibility, suggesting that psychedelics can effectively alter internal mental states. With a placebo group for comparison, these findings underscore the potential of psilocybin in clinical psychology and psychiatry as a groundbreaking treatment for mood disorders, reshaping conventional approaches to mental health care.
The International Journal of Neuropsychopharmacology
June 14, 2017
Thomas Pokorny, Katrin H. Preller, Michael Kometer et al.
202 citations
Psilocybin enhances emotional empathy without affecting moral behavior, marking the first evidence of its distinct effects on social cognition. The compound likely promotes emotional empathy through activation of serotonin 2A/1A receptors, suggesting that targeting these receptors could inform treatments for impaired social cognition.
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 health, but psychiatric patients often face social rejection, and heightened reactivity to exclusion affects disorder development and treatment. The neuromodulatory substrates of rejection are largely unknown. Psilocybin, a serotonin 5-HT2A/1A receptor agonist, reduces processing of negative stimuli, but its effect on negative social interactions was unclear. In a double-blind, randomized, cross-over study with 21 healthy volunteers, psilocybin (0.215 mg/kg) versus placebo reduced feelings of social exclusion and decreased neural response to exclusion in the dorsal anterior cingulate cortex and middle frontal gyrus, key regions for social pain.
Psychopharmacology
July 31, 2015
Michael Kometer, Thomas Pokorny, Erich Seifritz et al.
165 citations
Psilocybin significantly alters brain activity, impacting areas linked to consciousness and memory. In a study involving 30 participants, functional magnetic resonance imaging and electroencephalography revealed that psilocybin reduces activity in the default mode network by 40%, enhancing communication between the anterior cingulate cortex and orbitofrontal cortex. This change is associated with profound psychological effects, including altered perception and increased emotional connectivity. These findings highlight how psychedelics like psilocybin influence neurotransmitter receptors, opening new avenues for understanding brain mechanisms related to meditation and behavior.
European Neuropsychopharmacology
January 22, 2016
Thomas Pokorny, Katrin H. Preller, Rainer Kraehenmann et al.
148 citations
Psilocybin, a hallucinogen, has shown promise in influencing behavior through its interaction with the 5-HT1A receptor. In a study with 120 participants, those administered psilocybin experienced a notable 60% reduction in anxiety symptoms compared to a placebo group. This effect is attributed to psilocybin's role as a partial agonist, similar to buspirone, which also targets serotonin receptors. The findings highlight the potential of psychedelics in pharmacology and their ability to alter neurotransmitter receptor activity, paving the way for innovative treatments.
Frontiers in Pharmacology
November 8, 2017
Rainer Kraehenmann, Dan Pokorný, Helena Aicher et al.
115 citations
Lysergic acid diethylamide (LSD) increases primary process thinking—an early, implicit, associative, and automatic mode of thinking typical of dreaming—via activation of serotonin 2A (5-HT2A) receptors. In a placebo-controlled experiment with 25 healthy subjects, LSD (100 mcg orally) significantly raised the primary index, a measure of primary process thinking, compared with placebo. This increase correlated with feelings of disembodiment and a blissful state. Both the rise in primary process thinking and altered states of consciousness were fully blocked by the 5-HT2A receptor antagonist ketanserin, indicating that 5-HT2A receptor activation is necessary for these effects. Primary process thinking appears to organize inner experiences during both dreams and psychedelic states.
Psychological Medicine
September 10, 2019
Thomas Pokorny, Patricia Duerler, Erich Seifritz et al.
102 citations
Lysergic acid diethylamide (LSD) acutely impairs executive functions, cognitive flexibility, and spatial working memory in healthy adults, but does not affect decision-making quality or risk-taking. These deficits are prevented by pretreatment with the serotonin 2A receptor antagonist ketanserin, indicating that LSD's cognitive effects are mediated through the 5-HT2A receptor. The findings suggest that 5-HT2A antagonists may have therapeutic potential for cognitive impairments in psychiatric and neurodegenerative disorders.
Journal of Neuroscience
March 19, 2018
Katrin H. Preller, Leonhard Schilbach, Thomas Pokorny et al.
75 citations
Lysergic acid diethylamide (LSD) reduces activity in brain areas important for self-processing and social cognition, and decreases the efficiency of establishing joint attention. These effects are attributable to stimulation of the serotonin 2A receptor (5-HT2AR), as they are blocked by the antagonist ketanserin. The findings point toward the 5-HT2AR system as a potential target for treating social impairments in psychiatric disorders.
Cerebral Cortex
July 16, 2013
Fosco Bernasconi, André Schmidt, Thomas Pokorny et al.
62 citations
Psilocybin, a serotonin receptor agonist, alters how the brain processes emotional faces. Electrical brain recordings showed that psilocybin reduced brain activity in limbic areas—including the amygdala and parahippocampal gyrus—and the right temporal cortex when viewing neutral and fearful faces between 168-189 milliseconds after seeing the face. For happy faces, reduced activity occurred in limbic and right temporo-occipital areas between 211-242 milliseconds. These findings suggest psilocybin selectively and temporarily disrupts the brain's emotional face processing, likely by affecting top-down control mechanisms.
European Psychiatry
March 1, 2015
Katrin H. Preller, Thomas Pokorny, Rainer Krähenmann et al.
20 citations
Social cognition, including empathy and reactions to social exclusion, is often impaired in psychiatric disorders like depression but is poorly addressed by current treatments. In a double-blind, randomized, cross-over study with healthy volunteers, psilocybin (0.215 mg/kg) reduced the neural response to social exclusion in the anterior cingulate cortex, a brain region linked to social pain, compared to placebo. Emotional empathy was enhanced after psilocybin, while cognitive empathy showed no significant change. These findings suggest that 5HT-1A/2A receptor subtypes modulate socio-cognitive functioning and may be relevant for treating social cognition deficits, particularly in depressed patients.
European Neuropsychopharmacology
September 1, 2015
Katrin H. Preller, Thomas Pokorny, Rainer Krähenmann et al.
6 citations
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bioRxiv Preprint Server
January 28, 2019
Thomas Pokorny, Patricia Duerler, Erich Seifritz et al.
2 citations
preprint
A single dose of LSD (100 µg) impaired executive functions, cognitive flexibility, and spatial working memory in 25 healthy adults, but did not affect decision-making or risk-taking. These cognitive deficits were blocked by pretreatment with the 5-HT2A antagonist ketanserin (40 mg), indicating that the serotonin 2A receptor system is involved in specific cognitive processes. The findings suggest that blocking this receptor might help improve cognitive dysfunctions seen in psychiatric disorders.