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CHAPTER 1
Our Three Brains
BUSINESS STRATEGIST WILL McFARLAND once said something that resonated deeply with me: âOur success at work used to demand that we understand business acumen. Thatâs not enough anymore. Going forward, the leaders and successful businesspeople of the world will also have an understanding of how to manage their biology. That will make the difference.â All of us innately understand that our success ultimately relies on the three-pound gelatinous grayish-white blob in our head, but too often we fail to see just how much biology matters in the output of our lives. But the more we know about our biology, the more in control we can beâwhich is why weâre starting with this chapter, a brief primer on the master of human biology: the brain.
Ninety percent of what we know about the brain weâve learned in the past twenty years, and we still have only nicked the surface. The human brain is such a complex and wonderful thing that itâs unlikely weâll fully understand it in our lifetime. Indeed, the science is currently being amended, altered, and in some cases out-and-out changed. Some neuroscientists devote their entire careers to researching a square-millimeter slice of the brain, research that will keep them busy into their old age.
Our overall success in the world is reliant upon our ability to manage the constant dance between two of the three âbrainsâ we possessâthe human brain and the mammalian brain. The third and oldest brainâthe reptilian brainâ operates without our assistance. Those who effectively manage those first two brains, the human and the mammalian, are more likely to achieve what they want. This is the foundation for making the types of choices that can change your life for the better. In this chapter, weâll take a look at the architecture and operations of these three basic brains. In the next chapter, weâll explore the chemical messaging and what we can do to influence it. In the final chapter of this section, weâll work to understand how our environments affect those messages and what that means for the choices we make.
And now, your brains await your acquaintance.
REPTILE, MAMMAL, HUMAN
Interpersonal neurobiologist Dr. Daniel Siegel uses an easy hand model to teach the basic anatomy of the brain. Iâll walk you through it below, because itâs great for understanding the relationship between the three brains, but you can go to YouTube and watch Dr. Siegel demonstrate it yourself.
Start by holding your hand in front of you with your palm facing you. Your arm represents the spinal cord that comes up into the brain. The base of your hand is the base of the brain, and includes the brain stem and other physiology that comprises our most ancient brainâthe aforementioned reptilian brain. It operates the functions we donât think about, like respiration, perspiration, salivationâany of the â-tionsâ that are automatic and autonomic. The reptilian brain automates every moment of our life, and really doesnât care how we feel about it.
Now fold your thumb to the middle of your palm, creating the number four. In our model, the thumb represents a big group of structures known as the limbic system. This is the heart of the mammalian brain. Among the many things the limbic system does is detect what is most important in our environment. If something is dangerous, it puts that on top for us to deal with right away. It also notices dangerâs oppositeârewardâand can help us connect to the highly positive elements of the environment. Like the reptilian brain, it is on 24/7, scanning the environment constantly to make sure we sense a threat and notice when something feels good too. The mammalian brainâs architecture also facilitates memories and alerts us to pay attention and focus. The amygdalae in each hemisphere of the brain are part of the limbic system too; they serve as our chief relevance-detecting devices. These little almond-shaped structures detect things that are novel, surprising, rewarding, and threatening, to name a few. Snakes and spiders and dangerous things are always going to be relevant, but so are food and mates and smiling faces, given the right context. What do untrustworthy and trustworthy faces have in common? They both represent people we need to be looking out for, people that might be motivationally relevant at some pointâwhether itâs to run away from them or to affiliate with them.1 In essence, our amygdalae are facilitating a shift in our attention to things that are important to both our well-being and our survival.2
The mammalian brain has been described as the emotional center of the brain: It is not logical and, left to its own devices, it would cause us to act like an undisciplined three-year-old. Fortunately, if conditions are right, the mammalian brain has an overseerâthe third brain.
The third brain, the human brain, is the captain of the ship. To complete our hand model, curl your four fingers over your thumb. Looks like a human brain, huh? Thatâs the neocortex engulfing the mammalian brain. Itâs what separates us from our animal cousins in extraordinary ways. Whatâs the difference between humans and our closest animal relative, the chimpanzee? Although there is only a tiny genetic differenceâwe share 98.8 percent of our DNAâour prefrontal cortices, the parts of the neocortex right behind our forehead, are very different. The prefrontal cortex (PFC) is the executive center of the brain, and itâs the essence of the third brain. It thinks, reasons, analyzes, innovates, and manages the emotions that rise from the mammal part of the brain; in other words, it makes us distinctively human. This is the part of our brain that enables us to create everything in the world that is not naturalâthe book youâre reading, your clothes, your bed. Everything we invent is conceived of in the human PFC. Our cousins closest in prefrontal cortex volumeâchimpanzeesâ have smaller overall volume in their PFC than humans, but not by much.3,4 Still, they canât come close to what humans have concocted. In fact, there is no other beast on the planet that can do what we can do. The reasons for this boil down to many things, but the size and operations of the prefrontal cortex are among the biggest. Thatâs why we must give it the respect and care it is due.
The human and mammalian brainsâthe neocortex and limbic systemâ interact with each other during every moment of our life. The PFC allows us to take time to think about things; the slowing down allows us to have a more reasonable relationship with our emotions. The interplay between these two brains is where we see the difference between businesspeople who succeed and those who fail miserably. Many people make it into great schools and get excellent jobs because theyâre technically smart and have high IQs, but they often derail because they never learn to help their human brain manage the mammalian brain. Eventually, the mammalian brain can destroy careers and relationships if we do not recognize how to bring the human brain online when weâre feeling strongly about something, especially in times of crisis.
HOW OUR MAMMALIAN AND HUMAN BRAINS WORK TOGETHER
The emotions generated by our mammalian brain are messy, and they arenât governed by logic. They bring on automatic social responses, generated by what neuroscientist Matthew Lieberman calls the reflexive system or X system (because of the X in the word reflexive).5 The brain structures involved in the X system include elements of the limbic system as well as a component of the prefrontal cortex. As its name implies, this system reacts by reflex: if you hit it, it hits you back without thinking. The X system is also what makes us react emotionally to stimuli throughout the dayâlike those pesky emails or texts that cause us a pang of anxiety when they pop up. (We will address this issue of emotional impulse control in chapter 6, about managing willpower and focus.)
In Liebermanâs model, the X system is contrasted with the reflective system, or C system. While the X system draws mainly on the limbic system, the prefrontal cortex is the primary structure involved in the C system. The C system manages the X system into civility and appropriate choices. Left to its own devices, the X system would cause us to be aggressive and rude and messy. When met with a total jerk, the X system in us says, âStrangle the twit!â The C system says, âCareer-limiting move! Maybe we should talk it out.â
Emotional intelligence (EI) is the dance between the more rational C system and the emotional X system. EI is a set of noncognitive (i.e., non-IQ) attributes, and if we have high EI, our C system is effectively cooperating with and regulating the X system. EI allows individuals to navigate the day-to-day difficulties and obstacles of life, manage their own emotions, and bring about appropriate emotions in others, all in an effort to be successful. In fact, itâs a better predictor of individual workplace success and well-being in life than IQ and expertise.6,7
ACTIVATION
⢠Think about a recent circumstance when your response to a situation was not exactly what you intended. You might have been tired, under pressure, or overwhelmed by your workload.
⢠Reimagine the situation with your human brainâthe PFC, the C systemârunning the interaction. What if you had taken just a few moments before responding to allow the human brain to take control? What would your response sound like this time?
⢠Activate your PFC by literally waiting for about ten seconds before you respond. Take a few deep breaths and slow down. When you respond immediately, you are likely operating out of your emotional brain first, and that can be fraught with overintensity and inappropriate words. Your response regulated by your PFC will almost always be more successful.
⢠Avoid making big decisions when you are overly stressed or tired. Thatâs when the emotional brain comes out to play, and you donât want that brain making important calls in your life.
Some scientists8,9 estimate that we spend only about 2 to 10 percent of our waking hours in the C system and the rest in the X systemâwhich means that most of our time is spent on the animal side of nature, reacting, responding out of impulse, defaulting to the negative, and missing the positive. Thatâs somewhat understandable: the C system is much more energy intensive to operate, while instantaneous X system reactions are less expensive to operate. In short, most of us have to work to improve our emotional intelligence. We have to decide to spend the energy. Hereâs where we have an opportunity. Imagine if, through awareness and new choices, we could increase the time spent in the human brain by just 1 or 2 percent. Look at what has been created in the world when the human part of the brain has been engaged, even for just short spurts. We have some incredible goals to shoot for as humans, and the activities in this book are aimed at getting us in that C system more of the time.
CHAPTER 2
Maximize Your Moments Through Your Neurochemistry
VISUALIZE THE DIFFERENCE BETWEEN a day when youâre at the top of your game and a day when even the slightest nuisance sends you into a tizzy. On some days, everything falls into place no matter what the world throws our way. There are scads of emails to answer, a looming deadline, phone calls from home, curveballs from the boss, but we perform wellâmaybe even exceptionally well. Itâs like weâre in a kickboxing match with the demands of everyday life, and weâre fit and winning. Itâs exhausting, but itâs a good kind of exhausting. We may even feel energized at the same time. Then tomorrow comes, and it is completely different. Even the simplest task is a struggle. Why do we have these down days, even when weâre facing the same circumstances that we excelled in yesterday?
The neurochemistry of the brain has the power to alter our behavior, mood, and perspective on the same set of circumstances from day to day. In a nutshell, neurochemistry is the complicated balance of chemicals in our br...