Lynn Nadel (born 12 November 1942) is the Regents' Professor of psychology at the University of Arizona. Nadel specializes in memory, and has investigated the role of the hippocampus in memory formation. Together with John O'Keefe, he coauthored the influential 1978 book The Hippocampus as a Cognitive Map, which defended the theory that the hippocampus learns and stores cognitive maps of portions of space. He later advanced the multiple trace theory, which posits that the hippocampus is always involved in storage and retrieval of episodic memory, but semantic memory can be established in the neocortex. Nadel received a Ph.D. from McGill University in 1967, and joined the faculty of the University of Arizona in 1985, where he currently serves as director of the Cognition and Neural Systems Program. Nadel, together with John O'Keefe, received the 2006 Grawemeyer Award for their work in identifying the brain's mapping system. Nadel is editor-in-chief of the scientific journal, Wiley Interdisciplinary Reviews: Cognitive Science.