In the world’s largest study on psychedelics and the brain, a team of researchers from The Neuro (Montreal Neurological Institute-Hospital) and Department of Biomedical Engineering of McGill University, the Broad Institute at Harvard/MIT, SUNY Downstate Health Sciences University, and Mila—Quebec Artificial Intelligence Institute have shown how drug-induced changes in subjective awareness are anatomically rooted in specific neurotransmitter receptor systems.