The Triune Brain illustration from The three units of the human Brain -Júlio Rocha do Amaral, & Jorge Martins de Oliveira (image somewhat degraded to speed up download) Paul MacLean discovery of the The Triune Brain The Reptilian Brian The Limbic System (Paleomammalian brain) The Neocortex (Neomammalian brain) Links The neurologist Paul MacLean has proposed that our skull holds not one brain, but three, each representing a distinct evolutionary stratum that has formed upon the older layer before it, like an archaeological site :He calls it the "triune brain." MacLean, now the director of the Laboratory of Brain Evolution and...