http://www.drugabuse.gov/NIDA_notes/NNvol15N6/Research.html · Public domain

A neuroscientist who spent decades working out how neurons actually talk to each other — how a chemical signal arriving at one cell triggers changes deep inside it, a process called signal transduction. The discovery underpins modern understanding of memory, mood, and movement disorders, and won Greengard the 2000 Nobel Prize in Physiology or Medicine, shared with Arvid Carlsson and Eric Kandel. He spent his career at Rockefeller University and later supported Alzheimer's research through the Cure Alzheimer's Fund.