James H. "Jim" Fallon (born 18 October 1947) is an American neuroscientist. He is professor of psychiatry and human behavior and emeritus professor of anatomy and neurobiology in the University of California, Irvine School of Medicine. His research interests include adult stem cells, chemical neuroanatomy and circuitry, higher brain functions, and brain imaging. Fallon, who himself has the neurological and genetic correlates of psychopathy, has been categorized as a "pro-social psychopath", an assessment with which he concurs.
