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.
A new study has characterized for the first time, and in detail, the effects of mescaline on functional brain organization using fMRI in awake rats. The researchers examined both acute changes in brain activity and changes in resting-state networks and in the processing of sensory stimuli.
The results show that mescaline acutely produces a selective reduction of BOLD activity in the cerebellum. On the authors’ interpretation, this points to altered functional communication between the cerebellum and forebrain regions. At the same time, the analysis of resting-state connectivity showed increased global connectivity: under mescaline the cerebellum was more strongly connected with regions such as the hippocampus, thalamus, somatosensory cortex and midbrain.
Mescaline also changed the processing of sensory information. The normal neuronal response to reward-associated odor cues was abolished. Tests of prepulse inhibition, a measure of the filtering of acoustic stimuli, additionally showed frequency-dependent effects: while certain frequencies produced stronger filtering of stimuli, filtering was reduced at other frequencies.
The researchers conclude from this that under mescaline the cerebellum may take on an altered role as a sensory filter. Disturbed regulation of this filtering function could contribute to sensory information being processed differently, and in this way to psychedelic changes in perception.
The authors stress that the neuronal patterns of mescaline differ in some respects from those of other classic psychedelics such as LSD or psilocybin. Since the study was carried out in rats, however, the results must first be verified in human studies.
