Paul D. MacLean

Paul D. MacLean was a neuroscientist known for proposing the "triune brain" theory, which suggests that the human brain is made up of three interconnected layers reflecting different evolutionary stages. These layers are the reptilian brain (basic survival instincts), the limbic system (emotions and social behaviors), and the neocortex (advanced thinking and reasoning). This model helps explain how various brain functions interact, highlighting our instincts, emotions, and rational thought as parts of a complex, evolutionary timeline-driven structure. While simplified, his theory offers a useful framework for understanding human brain organization and behavior.