The Triune Brain

Paul McLean and other brain researchers discovered and published in the 1960s what the Ancients had discerned eons before. We each have three brains in our heads, and three of the Enneagram temperaments have one brain that is dominant in a crisis or in making quick decisions: we call this our Enneagram Triad. We are also connected across the Enneagram Mandala or circle to our other two brains. This forms our Triangle of support (See Triangles).

Paul McLean was the first of several brain researchers to discover in the 1950’s that we have two emotional brains and one thinking brain. He called them our Triune Brain (1960) and they were taught in the 1980’s and 90’s to psychotherapists like me. Bessel Van Der Kolk refers to the two emotional brains together as “the emotional brain” in his book, The Body Keeps the Score. Today, other neurologists have begun to distinguish more features in our brains, but for our purposes in understanding the Enneagram, Paul McLean’s version is sufficient.