Translated from our German original by AI. The German text was researched, written, and edited by the Psychedelia Foundation team and remains the authoritative version.
The psychedelic 2C-B changes the functional organization of the human brain in ways that resemble psilocybin but remain partly distinguishable from it. A study published in the journal Molecular Psychiatry is the first to systematically examine the acute neural effects of 2C-B in humans.
Twenty-two healthy adults took part in the double-blind, placebo-controlled crossover study. Across three sessions, participants received 20 milligrams of 2C-B, 15 milligrams of psilocybin, or placebo. Their brain activity was measured during the acute window using 7-Tesla resting-state fMRI. The subjective intensity of the acute effects did not differ significantly between 2C-B and psilocybin during imaging. In the psychedelic experiences recorded afterwards, however, anxiety-related ego dissolution was more pronounced under psilocybin.
Both substances led to a desegregation of functional brain networks: functional connectivity within particular networks decreased, while communication between different networks, and between cortical and subcortical regions, increased. The complexity of spontaneous brain signals rose under both substances as well.
The differences between the two psychedelics were pronounced too. 2C-B reduced the variability of dynamic connectivity between networks less than psilocybin did, and at the same time produced stronger increases in functional connectivity within transmodal networks. Global connectivity also showed different spatial patterns.
The researchers additionally compared the spatial distribution of the brain effects with PET-based maps of binding for various monoaminergic transporters and serotonergic receptors. The observed patterns could not be explained by the 5-HT2A receptor alone. Instead, the results suggest that the differing pharmacological profiles of 2C-B and psilocybin contribute to the specific changes each produces in functional brain dynamics.
The researchers also found a relationship between changes in functional organization and behavioral measures of the psychedelic effect. Decoupling of the transmodal axis of brain organization in particular emerged as a neurobiological marker of the subjective effects.
The study thus provides the first direct data on the human neurobiology of 2C-B, showing that this phenethylamine shares essential features of the network changes known from psilocybin while producing a pattern of functional brain dynamics of its own. The findings make 2C-B an interesting model for psychedelic neuroscience. They do not demonstrate a therapeutic benefit or any superiority over psilocybin; clinical studies with the relevant patient groups would be needed for that.
