THE TRIUNE BRAIN BY JOHN H. FREER, MD THE HOPKINSVILLE ATHENAEUM SOCIETY September 3, 2009 The three-in-one, what do you think of when you hear this phrase? Most of us will likely think of the Christian theological concept of the Trinity but have no fear, I am not going to violate the Athenaeum's prohibition by talking about religion but rather this evening I want to introduce another important three-in-one concept that of the three-in-one or triune brain. Let me see the hands of those of you who have heard of the Triune Brain? The Triune Brain is a hypothesis formulated by neurologist, Paul MacLean, MD in the 1950's. MacLean, a neurologist was originally interested n philosophy and changed to the study of science and medicine while taking a course on the philosophy of science. Dr. MacLean expanded on the earlier work of an American neurologist at Cornell University, James Papez, MD. In 1937 Dr. Papez described a neural pathways in the brain thought to be involved in the cortical control of emotion. Dr. MacLean conducted research on the assumption that observations of animal behavior are relevant to the understanding of the behavior of humans. MacLean was director of the Laboratory of Brain Evaluation and Behavior of the National Institutes of Mental Health in Poolesville, MD. Dr. MacLean studied the evolutionary development of the nervous system and described the human brain as a "triune brain" made up of three major layers or "brains" each representing a distinct evolutionary stratum that had formed upon the older layers before it, like an archaeological site. The three brains were established successfully in the course of human evolution. The oldest layer is the reptilian brain, reptilian system or "R" complex; the second oldest is the mammalian brain or the "limbic" system and the most recent, having been formed about 50, 000 years ago, is the neomammalian brain or neocortex. Each of the three brain layers represents an evolutionary stratum that has formed upon the older layers before it like an archeological city. Each is connected by nerves to the others; each has a separate function but all three layers interact. The three layers of the brain operate much like three interconnected biological computers, each with its own special intelligences, it's own subjectivity, each it's own sense of time and space and it's own memory. Each brain operates as its own brain system with distinct capacities for perceiving and responding to the environment and each can become dominant, depending on the circumstances. This evening we are going to look at the Triune Brain model and how understanding it can help us better understand our behavior and the behavior of others. This model has been a powerful tool in helping me better understand myself and others and I teach it to most of the service men and women with whom I work at Ft. Campbell. The Triune Brain hypothesis has forced us to rethink how the brain functions. Until this time we thought the highest level of the brain, the cortical hemispheres, the neocortex, dominated the two lower levels, the reptilian and limbic brains. MacLean has shown that this is not the case and that the physically lower limbic and the reptilian system can hijack the higher mental functions when they are aroused by an appropriate stimulus or trigger, such as a threat to our life or fear. It is interesting that many spiritual traditions have taught the similarities of the three phases of consciousness and even that of three different brains. In our Christian tradition, St. Paul, talks of this in the seventh chapter of Romans when he says, "It seems to be a fact of life that when I want to do what is right, I inevitably do what is wrong. I love to do God's will so far as my new man is concerned but there is something else deep within me, in my lower nature, that is at war with my mind and wins the fight and makes me a slave to the sin that is still within me. In my mind, I want to be God's willing servant but instead I find myself still enslaved to sin." Romans 7:21-24. As Walt Kelly's comic character, Pogo said, "We have met the enemy and they is us." St. Paul and historically Christianity and the major living religious traditions have seen the source of our personal trouble as residing outside in the world and in others, being alien to oneself. But it is the Animal, the Beast our brainstem and midbrain that is the source of this. I met LTC Dave Grossman at Ft. Campbell three years ago. His book, On Combat , is a book about the psychology and physiology of deadly conflict in war and peace. I have given it to nearly three hundred Ft. Campbell Service Member's most suffering from PTSD. LTC Grossman calls the brainstem and mid-brain the, "Puppy brain." He and I agreed this part of our brain is animal but we differed about it being a puppy. It is neither as nice nor as domesticated as a puppy. If it is canine, it is a wolf, a jackal or a hyena. The R-complex or reptilian brain is the oldest layer and is very primitive and animalistic. It closely resembles the brain of the modern day reptiles like snakes and lizards. It consists of the brains stem and cerebellum. Its main function is to make sure we stay alive and that out genes survive and are passed on to the next generation. The reptile brain is a part of one's unconscious. It is a part of the autonomic or involuntary nervous system. This brain controls our position in space, our balance and automatic functions like breathing, blood pressure and heartbeat. When it is "triggered" by external cues it automatically carries out a series of instinctual responses. For example, when we are driving our car and see a red light, it triggers an instinctual response to stop. The reptile brain has no feeling and cannot use words and would eat it's own alive and not even know or care. Some of the traits associated with the reptilian brain include: aggression, dominance, submission, mating, sex, rigidity, obsessiveness, compulsiveness, worship, greed and fear. It's main mode of operation is "Fight or Flight." Think of a wild animal defending its territory or fighting for its life or the life on one of it's kind and you have a good idea of kinds of behavior associated with this part of our brain. This part of one's brain never sleeps and is active 24/7. It is active even in deep sleep and dreaming. The French, market researcher Clotaire Rapelli, makes reference to the reptilian brain in his book, The Culture Code. In his book he claims in order to understand consumer's decision making, one needs to understanding the reptilian brain, which is key to understanding the unconscious. He says when consumers make decisions the reptilian brain always wins. Appealing to the reptilian trait's of fear have defeated National Health Insurance in the USA since its inception in 1919. In 1919, during the Presidency of Theodore Roosevelt, a rumor was circulated that National Health Insurance was a plot of the German Kaiser to take over America and it was defeated. During Harry Truman presidency, his effort to enact National Health Insurance was defeated after rumors that its passage was communistic and would have the Red Army marching in our streets. In 1993 the famous Harry and Louise ads said a vote for National Health Insurance would take away our right to choose our physician and take health care decisions away from the patient and their doctor. These ads instilled fear in the unconscious and were significant in again defeating National Health Insurance. The limbic system is our 'emotional brain" and makes one feel the way we feel when exposed to a certain stimulus (trigger). It gets it's name from the Latin, limbus-meaning girdle since it engirdles the reptilian brain like a girdle. It consists of the hippocampus (spatial memory), amygdla (associates events with emotions), mammillary body, anterior thalamus, and the cingulate body. The limbic system creates electrochemical messages that connect external information to memory, the retention of which is significantly increased when that information is presented in an emotionally charged context. This is why one is likely to remember events that created a strong positive or negative emotional response in you and why other people remember the things you said of did to them that made them feel a certain way. The limbic system is the source or emotions and instincts such as feeding, fleeing, fighting and sexual behavior. The limbic system cannot function on its own and must interact with the neocortex to process the emotion. The limbic system by and large operates on the Pleasure Principal in that it seeks pleasure and avoids pain. Because we are largely driven toward experiencing pleasure and avoiding pain the limbic system or emotional brain may have evolved to sense and counter balance the needs of the reptilian brain. One of the ways the limbic system does this is by insuring you obtain pleasure from activities such as eating and sex, so we are motivated to repeat these behaviors and that we obtain pain from behaviors that may hurt or endanger us and are motivated to avoid things like touching a hot stove. The limbic system is concerned mainly with self and species preservation and with all the parts connected to the hypothalamus it had extensive influence on human behavior. Without the emotional brain, we would keep doing the same things obsessively over and over in a ritualistic way, never learning from our mistakes. The limbic system is an important part of our brain and may control more of our behavior than we realize. We like to think most of our decisions are made on what we think when in reality, a large majority of our decisions are made on our "emotional state of mind"; on how we feel rather than on what we think. This said, a word of caution, because at times our emotions can "take over our mind" and change our thoughts. For example, when we go into road rage or fall in love. At those times it would be well if we would, "Stop and think" of "Take a breather" or "Walk away." The neocortex is the most recent part of the brain and is the "thinking" or rational part of our brain. Nearly every thing we think of as human is associated with the neocortex. The four attributes that most distinguish humans from the rest of the created order are our thumbs, toes, tears and laughter. Chip Walter's, a scientific journalist, in his excellent book entitled, Thumbs, Toes and Tears writes about these in detail. It should be noted that only humans have significant frontal lobes. These frontal lobes play an important role in many of the thinking processes that distinguish humans from other animals. The frontal lobes are important for abstract thinking, for imagining the likely consequences of actions and for understanding another person's feelings and motives. Injury or abnormal development of the frontal lobes can result in the loss of these abilities as the case of Phinaes Gage in 1848 demonstrated. An accident damaged the prefrontal cortex of Phinaes Gage and although he retained normal memory, speech and motor skills his behavior changed. He became irritable, quick tempered and impatient and at the most fundamental level he lacked judgment in his relationships. The normal ability to use tools including the tools of words and language is a function of the human neocortex and is awesome beyond words. Selma Fraiberg, MD, a psychiatrist and author of The Magic Years. In the chapter on speech and language entitled "The Magic of Words," she expresses this well. The neocortex also controls our higher processes such as logic, reasoning, creative thinking and the integration of sensory information. It controls the voluntary nervous system. Dr. MacLean refers to the cortex as "the mother of invention and the father of thought." In the human the neocortex takes up two thirds of the entire brain mass Although all mammals have a neocortex it is really small in comparison to that of the human neocortex. A mouse can function normally or nearly so without a cortex but a human without a cortex is a vegetable. The cortex is divided into the left and right hemispheres, the famous left and right brain. The left half of the cortex controls the right half of the body and the right half of the cortex controls the left half of the body. The right brain is more spatial, musical and artistic; while the left brain is more linear, rational and verbal. A problem with the neocortex is that it tends to be overpowered by the brains beneath it, especially the emotional brain; the limbic system. For example, experiencing the emotion of fear can cause the amygdala, in the emotional brain or limbic system to send out alarm signals to every part of the brain causing your brain to become more alert and ready to react to potential threats or danger in your environment. The brain then searches itself for relevant responses to the threat, which often take priority over other forms of thought and/or action. This response is often irrational, such as fighting or fleeing being carried out immediately, irrationally, even without thinking about it i.e. the fight or flight response. This kind of response could save one's life but this lack of neocortical dominance could also cause problems such as anxiety or panic attacks or PTSD when you react in pre-programmed, irrational ways to less than life threatening situations, essentially making one a helpless slave to your emotional or reptilian brain. Our reptilian brain does not stop working as the higher brain develops and is still fully functional in every adult. If your neocortex becomes overly stressed or deprived of essentials like food, water or oxygen or compromised by alcohol or other drugs, the neocortex loses dominance and the mask of Dr. Jekyll slips away and the beastly, demon of Mr. Hype appears with his primal thinking, lashing out in some thoughtless action. Punishment and/or redirection and correction of such uncontrollable “bad" behavior as a child teaches us to repress and redirect such animal, beastly, reptilian behavior into more creative and constructive outlets. If on the other hand the Beast is overly repressed and controlled by the neocortex this can produce a mind/body split and the neocortex, the conscience becomes a cruel taskmaster over the reptilian brain. However, the reptile brain cannot be denied and suppressed indefinitely and if locked away and handcuffed and deprived of food and water and some excitement for too long it will eventually come roaring out of the cage and eat you alive. It must be remembered that the Beast in us furnishes the energy of the basic drives and is the motivating force of one's personality. We must learn to accept and understand our basic drives the primitive/beastly feelings, so we can control rather than repress or harshly deny them. One must not deny or fear the reptile mind, the beast in us-this is the worst thing we can do with this part of our nature. It knows everything we do and think. As we grow and develop we learn to respect and care for this side of our nature so it will continue to shoulder the load; pull the wagon and serve us faithfully. The reptile mind has needs that are basic and powerful. They cannot, for long be denied or ignored and one should not be ashamed of them, instead one should use them by converting the energy they release for our intellectual and creative needs. The reptile mind loves excitement and consequently people like to do exciting, dangerous things like mountain climbing, racing, hang gliding, etc. because these activities satisfy some of the needs of the reptile mind. We should choose to play some physical games or master a physical skill in order to put us more in touch with our bodies. I close with a poem by Bryn Evans, "Our Brain" Learning can be quite a strain If we don't understand our brain It's made of part's one, two, three Each making up what's you and me. The first, deep down is very old Been there since dinosaurs we're told It's there to guarantee survival Only if we're safe and sound Will our thoughts shift to higher ground. The second, wrapped around the first Controls emotions, best and worst Happy, sad, upset of calm If too disturbed our learning harmed. The third part runs our higher thoughts It's where we process what we're taught Cells link up memories created Tricky problems negotiated. This bit's divided into two Strong left, strong right, which one are you? The left likes words and smaller bites The right-whole pictures, pattern, sights To sum up-this fantastic tool Will serve us well at home or school To keep it at its best we oughta Give it exercise and rest and water. BIBLIOGRAPHY Eruptingmind SelfImporvement Tips: the Triune Brain Model; Reptilian, Limbic and Neocortex: http://www.eruptingmind.com/reptilian-brain-triune-model/ Fraiberg, Selma. The Magic Years: Understanding and Handling Problems of the early Years. New York. Fireside. 1987. Grossman, LTC Dave. On Combat: The Psychology and Physiology of Deadly Conflict in War and in Peace. U.S.A. PPCT Research Publications. 2004. Rapaille, Clotaire. The Culture Code: An Ingenious Way to Understand Why People around the World Live and Buy as They Do. New York. Bradley Books, Inc. 2006. The Living Bible: Self-Help Edition. Wheaton, IL. Tyndale House Publishers. 1971. The Triune Brain: Effective Mind Control. http://www.effective-mind-control-.com/triune-brain.htm/ The Triune Brain. "Paul MacLean's triune brain hypothesis. http://kheper.net/topic/intelligence/MacLean.htm/ Walter, Chip. Thumbs, Toes and Tears and other traits that make us human. Walker Publishing Company, Inc, New York: 2006 Wikipedia, "The Triune Brain". http://en.wikipedia.org.wiki/Triiune_brain