Brain Rules by John Medina [Book Summary #1]

Rating: 10/10

Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School is an incredible book. The author solidifies his position as an authority on the brain by systematically keeping the reader interested while explaining the complexities of the brain. He utilizes and thoroughly explains tactics to learn, pique and keep interest, and many other valuable neurological activities. This book is entertaining and educational, I highly recommend it.

My Notes

Rule #1: Exercise boosts brain power.

-Our brains were built for walking--12 miles a day!

-The gold standard appears to be aerobic exercise, 30 minutes at a clip, two or three times a week. Add a strengthening regimen and you get even more cognitive benefit.


 Rule #2: The human brain evolved, too.

-Human brain is designed to (1) solve problems (2) related to surviving (3) in an unstable outdoor environment, and (4) to do so in nearly constant motion.

-Symbolic reasoning takes about 3 years to become fully operational

-3 sections of the brain:

1. Lizard brain--the stem--is the oldest. Its neurons regulate breathing, heart rate, sleeping, and waking.
2. Paleomammalian--"cat"--brain involves the 4 F's: fighting, feeding, fleeing, and fornicating. It contains the amygdale, which allows one to feel rage, fear, or pleasure; it's responsible for both the creation of emotions and the memories they generate. Also houses the hippocampus--converts your short-term memories into longer-term forms, and the thalamus, one of the most active, well-connected parts of the brain--a control tower for the senses. It processes signals sent from nearly every corner of your sensory universe, then routes them to specific areas throughout your brain. 
3. Prefrontal Cortex controls "executive functions": solving problems, maintaining attention, and inhibiting emotional impulses. 

-Learning performance may be deeply affected by the emotional environment in which the learning takes place.

Rule #3: Every brain is wired differently.

-What you do and learn in life physically changed what your brain looks like--it literally rewires it.

-The various regions of the brain develop at different rates in different people.

-No two people's brains store the same information in the same way in the same place.

-We have a great number of ways of being intelligent, many of which don't show up on IQ tests.

Rule #4: We don't pay attention to boring things.

- Emotions get our attention.

• Universal arousals: Can I eat it? Will it eat me? Can I mate with it? Will it mate with me? Have I seen it before?

-Meaning before details. 

• Experts' knowledge is not simply a list of facts and formulas that are relevant to their domain; instead, their knowledge is organized around core concepts or "big ideas" that guide their thinking about their domains. 

-The brain cannot multitask.

- The brain needs a break to digest new information.

-We are better at seeing patterns and abstracting meaning of an event than we are at recording detail.

-Emotional arousal helps the brain learn.

-Audiences check out after 10 minutes, but you can keep grabbing them back by telling narratives or creating events rich in emotion. 

Rule #5: Repeat to remember.  

-The brain has many types of memory systems. One type follows four stages of processing: encoding, storing, retrieving, and forgetting.

-Information coming into your brain is immediately split into fragments that are sent to different regions of the cortex for storage.

-Most of the events that predict whether something learned also will be remembered occur in the first few seconds of learning. The more elaborately we encode a memory during its initial moments, the stronger it will be.

-You can improve your chances of remembering something if you reproduce the environment in which you first put it into your brain.

-The more elaborately we encode info at the moment of learning, the stronger the memory.

*Info should be elaborate, meaningful, and contextual.

Rule #6: Remember to repeat.

-Most memories disappear within minutes, but those that survive this fragile period strengthen with time. 

-Long-term memories are formed in a two-way conversation between the hippocampus and the cortex, until the hippocampus breaks the connection and the memory is fixed in the cortex--which can take years.

-Our brains give us only an approximate view of reality, because they mix new knowledge with past memories and store them together as one.

-The way to make long-term memory more reliable is to incorporate new info gradually and repeat it in timed intervals.

-A great deal of research shows that thinking or talking about an event immediately after it has occurred enhances memory for that event, even when accounting for differences in type of memory.

*Author's idea for education: 25-minute modules, repeated 3x a day; review holidays every 3-4 days covering the material from the previous 72 to 96 hours (and yearly reviews of key concepts).

Rule #7: Sleep well, think well. 

-The brain is in a constant state of tension between cells and chemicals that try to put you to sleep and cells and chemicals that try to keep you awake.

-The neurons of your brain show vigorous rhythmical activity when you're asleep--perhaps replaying what you learned that day.

-People vary in how much sleep they need and when they prefer to get it, but the biological drive for an afternoon nap is universal.

-Loss of sleep hurts attention, executive function, working memory, mood, quantitative skills, logical reasoning, and even motor dexterity.

Rule #8: Stressed brains don't learn the same way.

-Your body's defense system--the release of adrenaline and cortisol--is built for an immediate response to a serious but passing danger, such as a saber-toothed tiger. Chronic stress, such as hostility at home, dangerously deregulates a system built only to deal with short-term responses.

-Under chronic stress, adrenaline creates scars in your blood vessels that can cause a heart attack or stroke, and cortisol damages the cells of the hippocampus, crippling your ability to learn and remember.

-Individually, the worst kind of stress is the feeling that you have no control over the problem--that you are helpless.

Rule #9: Stimulate more of the sense.

-Branding smell:

1. Match the scent with the hopes and needs of the target market
2. Integrate the odor with the "personality" of the object for sale.

-We absorb info about an event through our senses, translate it into electrical signals (some for sight, others for sound, etc.), disperse those signals to separate parts of the brain, then reconstruct what happened, eventually perceiving the event as a whole.

-The brain seems to rely partly on past experience in deciding how to combine these signals, so two people can perceive the same event very differently.

-Our senses evolved to work together which means that we learn best if we stimulate several senses at once.

-Smells have an unusual power to bring back memories, maybe because smell signals bypass the thalamus and head straight to their destinations, which include that supervisor of emotions known as the amygdala.

Rule #10: Vision trumps all other senses.

-We do not see with our eyes. We see with our brains.

-Vision is by far our most dominant sense, taking up half our brain's resources.

-What we see is only what our brain tells us we see, and it's not 100% accurate.

-The visual analysis we do has many steps. The retina assembles photons into little movie-like streams of information. The visual cortex processes these streams,some registering location and if an object is moving (dorsal stream), others registering what an object is and color (ventral stream). Finally, we combine that info back together so we can see.

-We learn and remember best through pictures, not through written or spoken words.

Rule #11: Male and female brains are different.

-The X chromosome that males have one of and females have two of--though one acts as a backup--is a cognitive "hot spot", carrying an unusually large percentage of genes involved in brain manufacture.

-Women are genetically more complex, because the active X chromosomes in their cells are a mix of Mom's and Dad's. Men's X chromosomes all come from Mom, and their Y chromosome carries less than 100 genes, compared with about 1,500 for the X chromosome.

-Men's and women's brains are different structurally and biochemically--men have a bigger amygdala and produce serotonin faster, for example--but we don't know if these differences have significance.

-Men and women respond differently to acute stress. Women activate the left hemisphere's amygdala and remember the emotional details. Men use the right amygdala and get the gist.

Rule #12: We are powerful and natural explorers. 

-Babies are the model of how we learn--not by passive reaction to the environment but by active testing through observation, hypothesis, experiment, and conclusion.

-We can recognize and imitate behavior because of "mirror neurons" scattered across the brain.

-Some parts of our adult brains stay as malleable as a baby's, so we can create neurons and learn new things throughout our lives.