Paul D. MacLean

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Paul D. MacLean
Born	1 May 1913  Phelps
Died	26 December 2007  (aged 94) Potomac
Education	Doctor of Medicine
Alma mater	Yale University Yale School of Medicine
Awards	Karl Spencer Lashley Award (1972)
Academic career
Institutions	Yale School of Medicine (1949–1956) University of Zurich (1956–1957) National Institute of Mental Health (1957–1985)

Paul Donald MacLean (May 1, 1913 – December 26, 2007) was an American physician and neuroscientist who made significant contributions in the fields of physiology, psychiatry, and brain research through his work at Yale Medical School and the National Institute of Mental Health. MacLean's evolutionary triune brain theory proposed that the human brain was in reality three brains in one: the reptilian complex, the limbic system, and the neocortex.