Besides being on the psychiatry faculty at Harvard University, Gruber is the director of Marijuana Investigations for Neuroscientific Discovery (MIND) and the director of the Cognitive and Clinical Neuroimaging Core at McLean Hospital outside of Boston. Her research focuses on clinical studies in marijuana users, often employing functional MRI (fMRI) technology to see exactly what parts of the brain the drug affects.

https://www.discovermagazine.com/mind/what-science-knows-about-marijuanas-health-benefits