Mescaline Changes Movement System Activity, Overall Brain Connections, and Sound Filtering in Awake Rats

Mescaline acutely disrupted cerebellar signaling, broadened brain connectivity, and altered sensory gating in awake rats.

This acute preclinical BOLD fMRI and prepulse-inhibition study in awake rats found cerebellar-selective BOLD suppression, global hyperconnectivity involving the cerebellum, loss of normal BOLD responses to rewarding olfactory stimuli, and frequency-dependent acoustic gating changes of +27.6% at 4 kHz, +27.3% at 20 kHz, and -16.4% at 12 kHz.

Because the findings come from an acute rat neuroimaging model, they may not generalize directly to human psychedelic effects.