David E. Olson is an American chemist and neuroscientist. He is an associate professor of chemistry, biochemistry and molecular medicine at the University of California, Davis. Olson is best known for his work investigating neuroplasticity promoting compounds, especially the potential of psychedelic drugs, including ketamine and serotonergic psychedelics, to alter brain structure and function. Olson also coined a term to refer to small molecules that are fast acting, durable neuroplasticity promoting compounds: psychoplastogens. Psychoplastogens are being developed to treat a wide variety of neuropsychiatric and neurodegenerative diseases, including depression, PTSD, and substance use disorders, among many others.