Molecular brain imaging of psychedelic action.
Paul Cumming, Klemens Egger, Gitte M. Knudsen
International review of neurobiology 2025 DOI: 10.1016/bs.irn.2025.02.005 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Review Peer reviewed |
|---|---|
| Topics | LSD Psilocybin |
| Keywords | Cerebral blood flow Metabolism Psychedelics: psilocybin Brain mechanisms: receptors 5-ht2a Neurological disorders Psychiatric disorders |
| Citations | 2 |
| Key findings | Molecular imaging studies of psychedelics have primarily focused on 5-HT2A receptors and cerebral perfusion or metabolism, but many other molecular targets remain unexamined, underscoring the need for more systematic research given the therapeutic potential of these substances. |
Abstract
Molecular brain imaging by positron emission tomography (PET) and single photon emission computer-tomography (SPECT) entails the mapping of the cerebral distribution of radiopharmaceuticals that track physiological processes such as blood perfusion and glucose metabolism, or the abundance in brain of specific molecular targets such as neuroreceptors. PET and SPECT emerged as useful in vivo research technologies in the 1980s, finding early application in the study of psychostimulant drugs. The past decade has seen growing use of molecular imaging methods in the study of psychedelic action, although the published literature remains comparatively small. The preponderance of publications cited in this review are SPECT studies of cerebral perfusion and PET studies of metabolism and neuroreceptors, the latter mainly focusing on the 5-hydroxytryptamine (serotonin) 5-HT2A receptors, which are largely responsible for the psychedelic action of classical psychedelic substances. There is some documentation of interactions of psychedelics at dopamine D2/3receptors in the striatum, but many other plausible molecular targets of psychedelic action await investigation by molecular brain imaging. The emerging role of psychedelics as treatments for neurological and psychiatric disorders calls for a broader and systematic investigation of their effects on brain function.
Comparable studies
Other narrative reviews on LSD, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Study of a New Schizophrenomimetic Drug—Sernyl | 1959 | Review | |
| Classic psychedelics: An integrative review of epidemiology, therapeutics, mystical experience, and brain network function. General population | 2019 | Integrative review | |
| The Pharmacology of Lysergic Acid Diethylamide: A Review | 2008 | Review | |
| Serotonin research: contributions to understanding psychoses | 2008 | Review | |
| ADVERSE REACTIONS TO PSYCHEDELIC DRUGS. A REVIEW OF THE LITERATURE | 1984 | Review |
Citations in the library
Cited by 2
- LSD: Mechanisms and relevance to the treatment of depression Neuroscience & Biobehavioral Reviews October 10, 2025
- Global increases in brain glucose metabolism following acute N,N-dimethyltryptamine and harmine administration in healthy volunteers: A randomised [18F]FDG-PET study. Journal of Cerebral Blood Flow & Metabolism June 1, 2026
Cites 40
- Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin Proceedings of the National Academy of Sciences January 23, 2012
- Psychedelic effects of psilocybin correlate with serotonin 2A receptor occupancy and plasma psilocin levels Neuropsychopharmacology January 26, 2019
- Antidepressant Effects of a Single Dose of Ayahuasca in Patients With Recurrent Depression Journal of Clinical Psychopharmacology December 11, 2015
- Psychedelics promote plasticity by directly binding to BDNF receptor TrkB Nature Neuroscience June 1, 2023
- Neurometabolic Effects of Psilocybin, 3,4-Methylenedioxyethylamphetamine (MDE) and d-Methamphetamine in Healthy Volunteers A Double-Blind, Placebo-Controlled PET Study with [18F]FDG Neuropsychopharmacology June 1, 1999
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