Translational Psychiatry
July 15, 2026
Annette Johansen, Pontus Plavén-sigray, Martin K Madsen et al.
Psychedelics such as psilocybin have been linked to enhanced neuroplasticity and symptom relief in affective disorders, but the neurobiological mechanisms and impact of environmental context remain unclear. Here, we tested whether a single dose of psilocybin (0.3 mg/kg) alters synaptic density in healthy individuals and whether setting-dependent subjective experience shapes this effect. Fifteen...
bioRxiv
April 13, 2026
Anders S. Olsen, Kristian Larsen, Drummond E. Mcculloch et al.
Abstract Psilocybin and other serotonergic drugs acutely alter human brain function and large-scale connectivity as measured with BOLD fMRI, but whether these effects are frequency-specific remains unknown. We applied multitaper spectral and cross-spectral analyses to resting-state fMRI data from 28 healthy volunteers scanned multiple times acutely following oral psilocybin administration (0.2...
Nature Medicine
April 1, 2026
Manesh Girn, Manoj K. Doss, Leor Roseman et al.
8 citations
Psychedelic drugs are re-emerging as promising scientific and clinical tools. However, despite a rapidly expanding literature on their therapeutic value, the neural mechanisms underlying psychedelic effects remain unclear. Resting-state functional magnetic resonance imaging studies of acute psychedelic effects, conducted independently by several research groups, have so far yielded fragmented...
medRxiv
January 16, 2026
Kristian Larsen, Patrick M. Fisher, Drummond E. Mcculloch et al.
1 citation
Classical psychedelics have regained interest for their potential to treat psychiatric and neurological disorders, and explore neural mechanisms supporting perception, cognition, and mood. Acute psychedelic effects have been linked to increases in brain complexity and entropy, but it is unclear if these changes are specific to psychedelics or reflect more general psychoactive effects. Here, we...
Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism
February 26, 2025
Kristian Larsen, Ulrich Lindberg, Brice Ozenne et al.
9 citations
Psilocin, the active metabolite of psilocybin, is a psychedelic and agonist at the serotonin 2A receptor (5-HT2AR) that has shown positive therapeutic effects for brain disorders such as depression. To elucidate the brain effects of psilocybin, we directly compared the acute effects of 5-HT2AR agonist (psilocybin) and antagonist (ketanserin) on cerebral blood flow (CBF) using pseudo-continuous...