In Brain Rules, John Medina discussed the tremendous growth of neuron connections before children are three years old and in puberty. He also pointed out the subsequent trimming of the over growth for those connections which were not used and reinforced again. One of his big ideas is: Infant brain development is not the critical key to intellectual success in life. The accumulated learning and exploration over one’s life span count a lot more. Curiosity and exploration are such inborn instincts for us before we put a brake on them later in life. Medina considered it a very important ingredient for a good education model to include the contact with real world challenges without damping the curiosity. In his view, the successful medical school model fits in that description. It has “a teaching hospital, faculties who work in the field as well as teach, and research laboratories.” Medical students have “consistent exposure to real world, to people who operates in the real world, and to practical research programs.”
I like Medina’s introduction of brain structures in the Brain Rules. The way he presented it made it so easy for me to understand. It became a foundation upon which I can ask more questions and build my understanding. The diagram of the brain structure in the book is worth checking out. Essentially, he divided brain into three parts:
·Brain stem, he called it lizard brain. This part is always working and it takes care of the basic housekeeping functions such as breathing and heart rate.
·Mid brain, he called it mammal brain. It has everything to do with animal survival. In Medina’s words, it “controls functions involve four F’s: fighting, feeling, fleeting, and…reproductive behavior.” There are three important parts in the mid brain: amygdala is related to the creation and memories of the emotions; hippocampus “converts your short-term memories into long-term memories”; thalamus is a “control tower for the senses” and it is “one of the most active, well-connected parts of brain.”
·Cortex, Medina called it human brain, “each region of the cortex was highly specialized, with sections for speech, for vision, for memory.”
Medina showed how the neuron connections are formed. He called it brain wiring.He explained the tremendous growth of neuron connections in babyhood and puberty, and the subsequent trimming of those connections when they are not used and reinforced later. He had an interesting point. He said, “By the time children are 3 years old, the connections in specific regions of their brains have doubled or even tripled. This has given rise to the popular belief that infant brain development is the critical key to intellectual success in life. That’s not true.” This makes sense to me and it certainly relieves a lot of my guilt toward my children. I am sure early development helps, but over a person’s life span, I believe the accumulated, consistent efforts later in life are far more important. Life is forgiving. There is not just one chance.
On one hand, the basic structure and functions of our brains are the same for all of us, on the other hand, the individual wiring in various regions is quite different from person to person and from men to women. “What YOU do and learn in life physically changes what your brain looks like – it literally rewires it.” “The physical changes result in the functional organization and reorganization of the brain.” And the more you use your brain, the more complex it will become. Since the brain is so sensitive to the external input, culture could significantly influence the brain wiring. Medina claimed that “no two people’s brains store the same information in the same way in the same place.”The maps of the brain for individuals “are established very early in life, and they remain stable throughout life.” Medina showed us three types of brain wiring: experience independent (basic housekeeping functions, such as digesting and breathing), experience expectant (visual acuity and language acquisition that we all need for survival), and experience dependent. He pointed it out that “different wiring doesn’t necessarily mean different intelligence.” But “the neurological differences can, at least in the case of language, predict performance”
One interesting fact that Medina showed was that, biochemically and structurally, men’s brains are different from women’s. Men have much larger amygdala, the one that is related to the creation and memories of emotions.In handling acute stress, men remember the gist and women remember the details. Men also can synthesize serotonin about 52% faster. Medina didn’t tell us much about the function of serotonin. From what I read elsewhere, it is a neurotransmitter in the modulation of mood and metabolism, and it seems to be associated with aggression. Medina said that the differences were a product of complex interaction between nature and nurture and he didn’t know whether the differences had any significance.
So why our brains are wired differently? Medina’s answer came from the evolutionary biology. He thought that the brain is “designed to solve problems related to surviving in an unstable outdoor environment, and to do so in nearly constant motion.” He called this brain’s performance envelop. He had this brief story to tell about the brain evolution. When the climate changed in Afica, our ancestors were forced to leave the tree tops and adapt to the grassland. In facing the sudden change, it was not an option to demand consistency, so they “gave up on stability and adapt to variation itself.” They started to walk on two legs instead of four limbs to see better and to save energy. Their strategy for survival was to become smarter instead of stronger. And their brain and their head grew bigger and bigger. To make a compromise between the big head and the birth canal, part of the brain development had to be done after the birth for many years. During that time, the parents had to be safe. Our ancestors chose the collaboration strategy to stay safe in the challenging world. The ability to understand other people’s psychological needs, their intentions and motivations became very important for collaboration. Medina believed that the symbolic reasoning was developed out of that necessity and it is what ultimately makes humans different from other animals. Symbolic reasoning is the ability to see things that are not there. For example, my children’s names on a piece of paper could evoke their images in my mind. With symbolic reasoning, people could build layers of meanings. That is what made language, writing, mathematics, and art possible. There is definitely a link between symbolic reasoning and culture creation. In the course of evolution, our ability to solve problems, learn from mistakes, understand each other, and build alliances was developed and refined. Learning played a huge role since it lets us “add new information under rapidly changing conditions.” The development of our brain responded by allowing the wiring flexibility to adapt to the environment and culture in which we found ourselves. “The adult brain throughout life retains the ability to change its structure and function in response to experience.” To survive, we need to know when we’ve made a mistake and we need to learn from it. To learn from our mistakes, we need to build a knowledge database from which we can retrieve useful information. Giving structure to the database through deep understanding would make retrieval possible and easier. To know when we’ve made a mistake, we need to have a chance to explore and improvise. The best learning would allow the building of a solid foundation for the knowledge database and allow creativity at the same time. The interaction of these two strengthens each other.
Using the evolutionary reasoning, Medina explained the importance of exploration. He said, “Our survival did not depend upon exposing ourselves to organized, pre-planned packets of information. Our survival depended upon chaotic, reactive information-gathering experiences. That’s why one of our best attributes is the ability to learn through a series of increasingly self-corrected ideas.”This ability is not emphasized enough for many of us. It reminded me an article I read a while ago. It was titled “The scientist as Rebel” by Freeman Dyson, published in The American Mathematical Monthly in November, 1996. If I remember it right, Dyson gave the mathematical formulation to the Feynman diagram and helped spread Richard Feynman’s ideas. Other than being a good mathematician, Dyson has a lot of insights with people. In this particular article, Dyson shared his low opinion about the so-called reductionism in science and mathematics. He used mathematician David Hilbert and physicist Einstein as examples. Later in life, both Hilbert and Einstein didn’t want to solve one problem at a time. Hilbert, “after 30 years of high creative achievement on the frontiers of mathematics”, wanted to “find a decision process that would operate on symbols in a purely mechanical fashion, without requiring any understanding of their meaning.” Einstein, with his “crowning achievement, the general relativistic theory of gravitation, grew out of a deep physical understanding of natural processes”, became virtually sterile after age 40 when he focused “more and more on the formal properties of equations that would unify the whole of physics.” He became actively hostile toward the idea of black hole, which is a solution of his equations of general relativity found by Oppenheimer and Snyder. “He thought that the black-hole solution was a blemish to be removed from his theory by a better mathematical formulation, not a consequence to be tested by observation.” The reason I found this article interesting is that it reminds me of how much we want to make sense and impose structures to what we encounter. I do it even when I read this book However, sometimes we can go too far and forget that new understanding, new directions, or new discoveries would come only if we feel comfortable with the chaos and can freely use all the tools at our disposal.
A big part of John Medina’s Brain Rules is about how to take care of the brain as a physical organ. Though I am surprised that Medina didn’t mention nutrition, the effect of exercise, sleep, and stress were extensively discussed. Exercise improves oxygen flow to the brain and increases a neuron generating protein called BDNF.Sleep helps the body effectively utilize the food consumed. Chronic stress could damage your blood vessels, disrupt your immune system, and make it hard for you to have regular sleep. Furthermore, it can push you into depression. Research showed the positive correlation between the school children’s performance and the emotional stability of their homes. The performance here includes both academic and social development. For adults, Medina suggested, “Three things matter in determining whether a workplace is stressful: the type of stress, a balance between occupational stimulation and boredom, and the condition of the employee’s home life.” Medina defined stress as an observable physiological response toward aversive situations which you have no control over. And here lies his big idea. The perception of control over our own life is one of the big keys in handling stress.
I just finished reading John Medina’s Brain Rules for the second time. It was published earlier this year and enjoys glowing reviews at Amazon.com. It’s worth checking out. My first reading went so smooth. I was thoroughly entertained and I hardly had any chance to stop and think what I really learned. I had to read it again, just to have another opportunity to understand many of the interesting topics presented in the book. Medina has very stringent requirements for any research results to show up in his book.The Medina Grump factor summarized the criteria he used: research must be published in a peer-reviewed journal and it must be successfully replicated. I assume he did his best to provide us with reliable information. Medina himself is a developmental molecular biologist and his “research expertise is the molecular basis of psychiatric disorders.” The research results Medina referred to touched on so many different disciplines, ranging from biology of the brain to the cognitive behaviors of people, medicine, experimental psychology, cognitive neuroscience, education research, and evolutionary biology, just to name a few.Each of these disciplines offers a different perspective and it’s great that Medina could bring them together. However, that is also where I have the biggest problem. After reading through, I don’t have a coherent picture of the brain. I wish I can see clearly, with each rule, that this is what we know for sure about the brain, at the structural level, at the physiological and biochemical level, at the empirical and behavior level, etc, and this is what we can infer from the hard evidence and apply in business and education. Not every rule could be explained at the various levels. Perhaps what we currently know in all the research fields doesn’t allow us to construct such a coherent picture. Medina said that the book was a call for research. Part of the value of the book lies in the ideas proposed and questions asked. I will certainly pay more attention to the new development in the brain research from now on.
. Here is the list of his 12 rules on the back cover
·WIRING | Rule #3: Every brain is wired differently
·ATTENTION | Rule #4: We don't pay attention to boring things
·SHORT-TERM MEMORY | Rule #5: Repeat to remember
·LONG-TERM MEMORY | Rule #6: Remember to repeat
·SLEEP | Rule #7: Sleep well, think well
·STRESS |Rule #8: Stressed brains don't learn the same way
·SENSORY INTEGRATION | Rule #9: Stimulate more of the senses
·VISION | Rule #10: Vision trumps all other senses
·GENDER | Rule #11: Male and female brains are different
·EXPLORATION | Rule #12: We are powerful and natural explorers
I don’t quite get why Medina structured his book the way it is and why in that particular order.For me to understand it, I need to structure everything I learned from this book with four central themes:
·How to take care of the brain as a physical organ: rule #1 (exercise), #8 (stress), and part of #7 (sleep),
·Individual differences in the brains: rule #2 (wiring), #11 (gender)
·What might have been the causes of the brain differences and how we should develop further along that line: rule #2 (survival), #12 (exploration)
·The best way to learn: rule #4 (attention), #5 (short-term memory), #6 (long-term memory), #9 (sensory integration), #10 (vision), and part of #7(sleep).
We will focus on the first theme in this part. For taking care of brain as a physical organ, Medina’s rules of exercise, stress, and sleep all make sense. Though, I wish he has one more rule about nutrition.
Exercise. Except for my brother-in-law, I’ve never heard anyone who thought exercise was bad. Exercise provides maintenance and improvement for the entire body. Specifically for the brain, exercise improves blood flow (more oxygen and nutrients to the brain) and increases protein BDNF (Brain Derived Neurotrophic Factor). Oxygen helps remove the waste from the body and empirically it correlates with the cognitive performance. BDNF is supposed to act like a fertilizer for the neurons. I don’t quite get the causal link between exercise and BDNF generation. “Exercise also regulates the release of the three neurotransmitters most commonly associated with the maintenance of mental health: serotonin, dopamine, and norepinephrine.” For me, the benefit of increased oxygen flow is enough to convince me to have an exercise regimen. One of the interesting suggestions Medina made is to take exercise breaks instead of coffee breaks. He even put a treadmill in his office and tried to work on his laptop while walking on the treadmill. From my experience, certain types of thinking require so much concentration that the body has to be absolutely still. I’d alternate thinking and exercising.According to Medina exercise is THE FACTOR that predicts how well we will age. This is in direct contradiction with my personal observations. I understand that he draws his conclusion based on statistics and I derive my understanding by observing people I know. Still, I don’t believe that the physically active life style is the single most important predictor for graceful aging. One’s curiosity, wisdom, and one’s relationship with oneself and other people are far more important. At the end of the day, if you still have something you strongly desire to do, if you still have fierce determination, if you have the wisdom and judgment to determine how far you can still push yourself in a sustainable way, and if you have big enough heart to relate to and connect with other people from different age groups and not just to commiserate, you are far more likely to age gracefully.
Sleep. According to Medina sleep deprivation decreases the body’s ability to make use of the food consumed. “The ability to make insulin and to extract energy from glucose begins to fail miserably, and you find a marked need to have more of it, because the body’s stress hormone levels begin to rise in an increasingly deregulated fashion.” Prolonged sleep deprivation “appear to accelerate parts of the aging process.”Not many adults I know really wake up naturally in the morning, Medina recommended nap in the afternoon even if you have enough sleep at night. For me, 15-20 minutes nap is one of the most refreshing experiences I’ve ever had. The trick is that you have to get up after the preset time, even if you still feel tired.
Stress. People talk about stress all the time. What is stress anyway? Medina defined stress as a measureable/observable aroused physiological response toward something aversive that you have no control over. When the body senses the stress, the hypothalamus in the brain notifies the adrenal glands on top of the kidney to release stress hormones adrenaline and cortisol into the bloodstream. In the short term, the stress hormone could regulate the blood pressure and boost cardiovascular performance to deal with any dangerous or unexpected situations. But, if the stress is chronic, too much stress hormone is left in the blood for too long, it “stops regulating surges in your blood pressure”. This could cause damage of the blood vessels. Medina told us that the hippocampus (the part of the brain that is essential for human memory) had lots of cortisol receptors, which could disconnect cells from neural networks or stop generating new neurons. I wish I can have a clearer understanding on how the stress response works physiologically. Chronic stress can also push “people into depression, which is a deregulation of thought processes, including memory, language, quantitative reasoning, fluid intelligence, and spatial perception.”The worst thing is that many depressed people don’t see a way out. Given the high divorce rate in this country, it’s not surprising that the biggest chronic stressor is the hostility at home for many people. Medina mentioned John Gottman’s marriage intervention research and practice. Getting a relief from marital stress not just helps the adults involved; it also helps children perform better at school. If you experience a lot of tension at home, Gottman’s work might be worthwhile to check out.A friend of mine used to say that the best thing you can do for your children is to love your spouse so you can create an emotionally stable and secure home for your children. I can’t agree with that more. Stress itself doesn’t necessarily break you. The effect on you “depends on the length and severity of the stress, your perception of the stress, and your body”. We could make some lifestyle choices to let in fewer stressors and perhaps also work on our perception and interpretation of the stressful situations. Ultimately there are only two effective ways to handle stress, Medina’s “getting control back into your life”, and James Loehr’s stress and recovery cycles. These two approaches complement each other.
Have you ever wondered how your brain works and how you can make the most of it? John Medina’s Brain Rules brought together many of the latest research results, ranging from biology of the brain to the cognitive behaviors of people. The book is very accessible, full of stories and personal experiences. To do some justice to the big ideas, I will write a series to cover the most important few. One of the big ideas is about learning. Learning causes physical change in the brain and the change is unique for each individual. The physical change will happen regardless of our age and we can all be life-long learners. To facilitate learning, we need to pay attention to two instincts of our brain: the database instinct and the improvising instinct. The former lets us construct a richly structured knowledge database, organized around core concept or big ideas, about deeply understood subjects. With this database, we can learn from our mistakes. The later lets us improvise off that knowledge database.With improvisation and exploration, we’ll know when we’ve made a mistake. The best learning takes advantage of the interaction between these two and allows ideas to develop and self-correct.
