Opiate receptors are found throughout the brain and body. There is a dense concentration of opiate receptors in the limbic system (emotional brain layer or pain/pleasure center). The densest concentration is in the frontal lobes of the human brain. (Pert, Candace, PhD. Molecules of Emotion. p 123, 134-135. NY: Scribner, 1997; Pert, Candace, PhD Your Body is Your Subconscious Mind. CO: Sounds True, 2000.)