By using the serotonin receptor (5-HT2AR) antagonist ketanserin, this study (n=22) found that this inhibited the forming of meaningful/personal relevant connections that were made under the influence of LSD (100μg). This confirms the idea that this 5-HT2AR is crucial for generating meaning.
Abstract of The fabric of meaning and subjective effects in LSD-induced states depend on serotonin 2A receptor activation
“A core aspect of the human self is the attribution of personal relevance to everyday stimuli enabling us to experience our environment as meaningful. However, abnormalities in the attribution of personal relevance to sensory experiences are also critical features of many psychiatric disorders. Despite their clinical relevance, the neurochemical and anatomical substrates enabling meaningful experiences are largely unknown. Therefore, we investigated the neuropharmacology of personal relevance processing in humans by combining fMRI and the administration of the mixed serotonin (5-HT) and dopamine receptor (R) agonist lysergic acid diethylamide (LSD), well known to alter the subjective meaning of percepts, with and without pretreatment with the 5-HT2AR antagonist ketanserin. General subjective LSD effects were fully blocked by ketanserin. In addition, ketanserin inhibited the LSD-induced attribution of personal relevance to previously meaningless stimuli and modulated the processing of meaningful stimuli in cortical midline structures. These findings point to the crucial role of the 5-HT2AR subtype and cortical midline regions in the generation and attribution of personal relevance. Our results thus increase our mechanistic understanding of personal relevance processing and reveal potential targets for the treatment of psychiatric illnesses characterized by alterations in personal relevance attribution.”
Authors: Katrin H. Preller, Marcus Herdener, Thomas Pokorny, Amanda Planzer, Rainer Kraehenmann, Philipp Stämpfli, Matthias E. Liechti, Erich Seifritz & Franz X. Vollenweider
Notes on The fabric of meaning and subjective effects in LSD-induced states depend on serotonin 2A receptor activation
The study analysed data from the same participants as Barrett et al. (2017).
This study was supported in part by the Usona Institute and the Heffter Research Institute.
Summary of The fabric of meaning and subjective effects in LSD-induced states depend on serotonin 2A receptor activation
Results
Subjective Effects of LSD and Role of 5HT2AR
Participants underwent three treatment conditions: placebo + placebo (Pla), placebo + lysergic acid diethylamide (LSD) or ketanserin + LSD (Ket + LSD). The LSD treatment condition resulted in greater scores on 9 of 11 Altered States of Consciousness scales than the Pla and Ket + LSD treatment conditions.
Find this paper
https://doi.org/10.1016/j.cub.2016.12.030
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Cite this paper (APA)
Preller, K. H., Herdener, M., Pokorny, T., Planzer, A., Kraehenmann, R., Stämpfli, P., ... & Vollenweider, F. X. (2017). The fabric of meaning and subjective effects in LSD-induced states depend on serotonin 2A receptor activation. Current Biology, 27(3), 451-457.
Study details
Compounds studied
LSD
Topics studied
Healthy Subjects
Study characteristics
Original
Placebo-Controlled
Double-Blind
Randomized
Bio/Neuro
Participants
22
Humans
Authors
Authors associated with this publication with profiles on Blossom
Katrin PrellerKatrin Preller is one of the upcoming researchers, currently at the University of Zurich and Yale University, and is focused on the neurobiology and pharmacology of psychedelics.
Matthias Liechti
Matthias Emanuel Liechti is the research group leader at the Liechti Lab at the University of Basel.
Franz Vollenweider
Franz X. Vollenweider is one of the pioneering psychedelics researchers, currently at the University of Zurich. He is also the director of the Heffter (sponsored) Research Center Zürich for Consciousness Studies (HRC-ZH).
Institutes
Institutes associated with this publication
University of ZurichWithin the Department of Psychiatry, Psychotherapy and Psychosomatics at the University of Zurich, Dr Mialn Scheidegger is leading team conducting psychedelic research and therapy development.
Compound Details
The psychedelics given at which dose and how many times
LSD 100 μg | 1xLinked Research Papers
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