Review: Brain Rules

Brain is one of the center of our life yet the most complex one to understand. As a molecular biologist, John Medina serves well-explained insights on “why” our brain works in a certain way, empowering us to harness its potential in our everyday lives in Brain Rules. Based on the discovery of how our brain works, Medina also offers some suggestions to revolutionize public policies, specifically in education system and workplace. Some of them seem impossible to me because I think they are too complicated to accommodate millions of individual brain patterns. Could this be the groundbreaking spark that ignites a new era of visionary policy maker? Only time will tell.

Summary: 12 Brain Rules

1. Survival: the human brain evolved, too.

Two powerful features of the brain:

A database to store a fund of knowledge → allows us to know when we’ve made mistakes.
The ability to improvise off that database → allows us to learn from our mistakes.

The Prefrontal cortex

the masterpiece of evolution.
the brain region that distinguishes humans from all other creatures.
governs several uniquely human cognitive talents, called “executive functions“: solving problems, maintaining attention, and inhibiting emotional impulses → controls many of the behaviors that separate us from other animals.

Brain stem

most ancient neural structure
controls most of body’s housekeeping chores: breathing, heart rate, sleeping, walking.
Sitting atop brain stem: “mammalian brain” → more to do with animal survival: fighting, feeding, feeling, and reproductive behavior.

Hippocampus

converts short-term memories into longer-term forms

Cortex

each region of cortex is highly specialized, with sections for speech, vision, memory

2. Exercise: exercise boosts brain power.

Brain became the most powerful in the world under conditions where motions was a constant presence.
Exercise → improves cardio fitness → reduces the risk for diseases and more mentally alert.

How exercise affects brain function?

Exercise provides body greater access to the oxygen and the food
Exercise → increase blood flow across the tissues of body → blood flow improves because exercise stimulates the blood vessels to create a powerful, flow-regulating molecule called nitric oxide. As the flow improves, the body makes new blood vessels, which penetrate deeper and deeper into the tissues of the body → allows more access to the bloodstream’s good and services: food distribution and waste disposal → the more exercise, the more tissues we can feed and more toxic waste to remove.
In brain:
- Exercise increase blood volume in dentate gyrus (a vital constituent of the hippocampus, a region deeply involved in memory formation) → increase likely the result of new capillaries, allows more brain cells greater access to the blood’s waitstaff and hazmat team.
- Exercise → aids in the development of BDNF → keeps existing neurons young and healthy and makes them more ready to connect with one another + encourages neurogenensis (the creation of new cells).
- Exercise increase the level of usable BDNF inside cells most sensitive to area in the hippocampus and buffers against the negative molecular effects of stress → improve memory formation.

Why exercise makes us more mentally alert?

A lifetime of exercise → elevation in:
- cognitive performance
- fluid-intelligence tasks, which test the ability to reason quickly, think abstractly, and improvise off previously learned material in order to solve a new problem
Based on research on a group of elderly couch potatoes:
- Exercise can improve mental abilities after as little as 4 months of aerobic exercise.
Based on research on a school-age children:
- After 12 weeks, cognitive performance had improved significantly compared with pre-jogging levels. When the exercise program was withdrawn, the scores plummeted back to their pre-experiment levels.

What type of exercise must you do and how much?

walk several times a week → benefitting brain
aerobic exercise, 30 mins at a clip, 2 or 3 times a week. Add a strengtheing regimen → more cognitive benefit

Exercise and dementia or depression

Lifetime risk for general dementia is literally cut in half if participate in exercise.
- Reduce odds of getting the disease by more than 60%.
Twice a week of 20-minute walk each day → cut risk of having stroke.
Exercise regulates the release of most of the biochemicals associated with maintaining mental health.
Exercise is beneficial immediately and over the long-term for depression and anxiety.
Exercise is not a substitute for psychiatric treatment.

Exercise and kids

Physically fit children identify visual stimuli much faster than sedentary ones → concentrate better.

3. Sleep: sleep well, think well.

How much sleep do we need?

Unknown, generalizations of how many hours of sleep do we need across people don’t work.
Sleep schedules are dynamic; change with age, gender, and whether or not you are going through puberty.

Benefit of sleep

Enhance tasks that involve visual texture discrimination (the ability to pick out an object from an ocean of similar-looking objects), motor adaptations (improving movement skills), and motor sequence learning.
The type of learning that most sensitive to sleep improvement is that which involves learning a procedure.
Healthy night’s sleep can boost learning significantly: sleep on the problem that we have → we will have clearer idea, solutions after we sleeping.

Sleep deprivation leads to brain drain.

Whatever amount of sleep is right for you, when robbed of that, bad things really do happen to your brain.
When sleep deprived happens:
- The body’s ability to utilize the food they are consuming falls by about 1/3.
- The ability to make insulin and to extract energy from the brain’s favorite source, glucose, begins to fail miserably. At the same time, you find a marked need to have more of it, because the body’s stress hormone levels begins to rise in an increasingly deregulated fashion. If you keep up the behavior, you accelerate parts of the aging process.
- Hurts attention, executive function, working memory, mood, quantitative skills, logical reasoning ability, general math knowledge.
- Affects manual dexterity. include fine motor control, and even gross motor movements, such as the ability to walk in a treadmill

4. Stress: stressed brains don’t learn the same way.

Three part definition that covers the bases of stress:

If all three of these are happening simultaneously, a person is stressed:

A measurable physiological responses
A desire to avoid the situations
A loss of control

We’re built for stress that lasts only seconds.

Sensory systems detect stress → the hippocampus signals adrenal glands to dump adrenalin (norepinephrine) in bloodstreams. The second wave of our defensive reaction to stressor, cortisol, is also released. In small doses, it wipes out most unpleasant aspect of stress, returning us to normalcy.

Stress in school performance

Stress affects learning. One might predict that children living in high-anxiety households would not perform as well academically as kids living in more nurturing households.
Physical health deteriorates; truancy and absenteeism increase.
- The absenteeism may occur because stress is depleting the immune system which increase the risk of infection.
Children living in hostile environments are greater risk for certain psychiatric disorder, such as depression and anxiety disorders.

What makes a workplace stressful?

Three things matter in determining whether your workplace is stressful or productive:

The type of stress you experience
The balance between stimulation and boredom in your job
The condition of home life

Doing the same tired thing day after day → brain-numbing tedium → source of stress.

Studies show that a certain amount of uncertainty can be good for productivity, especially for bright, motivated employees. They need a balance between controllability and incontrolability. Slight feelings of uncertainty may cause them to deploy unique problem solving strategies.

5. Wiring: every brain is wired differently.

When you learn something, the wiring in brain changes.

You can wire and rewire your brain with the simple choice of which musical instrument—or professional sport—you play.

We expect that kids should be able to read by age 6.

Studies show that about 10% of students do not have brains sufficiently wired to read at that age.

6. Attention: we don’t pay attention to boring things.

Wilbert McKeachie in his book Teaching Tips:

Typically, attention increases from the beginning of the lecture to 10 minutes into the lecture and decreases after that point.
Suggestion: find a way to get and hold somebody’s attention for 10 mins, then do it again.

Emotions get our attention

Emotionally charged events are better remembered than neutral events
- When your brain detects an emotionally charged event, your amygdala releases dopamine into system → dopamine greatly aids memory and information processing.

Meaning before details

Present information in a locally organized, hierarchical structure → allows people to derive the meaning of the words to one another.
If you want people to be able to pay attention, don’t start with details. Start with the key ideas and, in a hierarchical fashion, form the details around these larger notions.

7. Memory: repeat to remember.

Hermann Ebbinghaus, 19th-century German researcher:

People usually forget 90% of what they learn in a class within 30 days.
One could increase the life span of a memory by repeating the information in timed intervals.

repetition fixes memories

Memory may not be doxed at the moment of learning, but repetition is the fixative.
The timing of the repetitions is a key component: repeated exposure to information in spaced intervals provides the most powerful way to fix memory into the brain.

repetition must be spaced out, not crammed in.

Harvard psychology Dan Schacter: if you want to study for a test you will be taking in a week’s time, and are able to go through the material ten times, it is better to space out the ten repetitions during the week than to squeeze them all together.

8. Sensory Integration: stimulate more of the senses.

Brain likes sensory integration:

The brain’s compromise between what you hear and what you see—its need to attempt integration.

Why does the brain have such powerful integrative instincts?

At multisensory environment, our muscles react more quickly, our eyes react to visual stimuli more quickly, and our threshold for detecting stimuli improves.
The extra cognitive processing of information helps the brain integrate the new material with prior information
Smell boosts memory all by itself.
- Called The Proust effect.
- Marcel Proust: smell has the unique advantage of being able to boost learning directly, without being paired with another sense. That’s because it is an ancient sense, not fully integrated with the resy pf the brain’s sensory circuitry but instead closely wired to the emotional learning centers to the brain. However, this is true for only certain types of memory. Odors appear to do their finest work when subjects are asked to retrieve the emotional details of a memory.

9. Vision: vision trumps all other senses.

Many people think that the brain’s visual system works like a camera, simply collecting and processing the raw visual data provided by our outside world. Seeing seems effortless.

Nothing in that last sentence is true. The process is extremely complex, seldom provides a completely accurate representation of our world, and is not 100% trustworthy. We actually experience our visual environment as a fully analyzed opinion about what the brain thinks is out there.
There is a region in the eye where retinal neurons, carrying visual information, gather together to begin their journey into deep brain tissue. That gathering place is called the optic disk. It’s a strange region because there are no cells that can perceive sight in the optic disk. It is blind in that region—and you are, too. It is called the blind spot and each eye has one. Do you ever see 2 black holes in your field of view that won’t go away? That’s what you should see. But your brain plays a trick on you. As the signals are sent to your visual cortex, the brain detects the presence of the holes examines the visual information 360 degrees around the spot, and calculates what is most likely to be there. Then, like a paint program on a computer, it fills in the spot. The process is called “filling in,” but it could be called “faking it.” Some scientists believe that the brain simply ignores the lack of visual information, rather than calculating what’s missing. Either way, you’re not getting a 100% accurate representation.

10. Music: study or listen to boost cognition.

Music training boost language skills.

In one study: boosts both motor skills (writing) and auditory skills (word recognition)—direct improvements in language processing.

The connection between speech and music

Music processing in the brain may partially overlap to create a shared region. The brain has regions that are speech-specific (red domain) and music-specific (blue domain). But speech and music also share some regions in common-psychologically and physiologically (purple domain). The purple domain is the reason that music training affects aspects of speech: if you improve one, you can also improve the other.

Music changes your mood.

Music induces hormonal changes: dopamine, cortisol, and oxytocin.

Dopamine
- Hear favorite music → bodies dump dopamine into a specific part of brain.
- Hear music that gives goose bumps (called musical frisson) → stratial system is activated → dopamine released.
Cortisol
- Listening to classical or meditation music had the greates effect.
Oxytocin
- Plays a huge role in social bonding.
- Stimulates temporary feelings of trust, orgasms, lactation, and even birth.
- When people sing as a group → oxytocin courses through brain.
- A fair indicator of feelings of trust, love, and acceptance. → that’s why people in a choir often report feeling so close to each other

Most studies above don’t prove cause and they’re all done in a lab setting → further research is needed.

11. Gender: male and female brains are different.

Differences between men’s and women’s brains can be viewed from several lenses: genetic, neuroanatomical, and behavioral

Mental illness

Males are more severely afflicted by schizophrenia.
Women are more likely to get depressed than men.
Males have a greater tendency to be anti-social.
Females have more anxiety.

Emotions and stress

The brain’s amygdala aids in the creation of emotions and our ability to remember them.
Men handled the experience by firing up the amygdala in their brain’s right hemisphere. Their left was comparatively silent. women handled the experience with the opposite hemisphere. Their left amygdala up, their right comparatively silent.
Women recall more emotional autobiographical events, more rapidly and with greater intensity, than men do.
Women more vivid memories for emotionally important events
Under stress, women tend to focus on nurturing their offspring, while men tend to withdraw. This tendency in females has sometimes been called “tend and befriend.”

Verbal communication

Women tend to use both hemisphere when speaking and processing verbal information. men primarily use one. Women tend to have thick cables connecting their 2 hemispheres. Men’s are thinner → the reason why language and reading disorders occur approximately twice as often in little boys as in little girls.women also recover from strike-induced verbal impairment better than men.
Girls seem verbally more sophisticated than little bots as they go through the school system. They are better at verbal memory tasks, verbal fluency tasks, and speed of articulation.

12. Exploration: we are powerful and natural explorers.

Babies test everything → sensory observation

42 minutes old: Newborns can imitate.
12 months old: infants analyze how object act.
18 months old: objects still exist if you can’t see them
- Before 18 months of age, still believes that if an object is hidden from view, that object has disappeared
- Object permanence: even if removed from view, it has not disappeared
  - An important concept to have if you live in the savannah. Saber-toothed tigers still exist, for example, even if they suddenly duck down in the tall grass. those who didn’t acquire this knowledge usually were on some predator’s menu.
8 months old: your preferences aren’t the same as mine
- Around 14 months, toddlers think that because they like something, the whole world likes the same thing
- Around 18 months old, they begin to learn that “what is obvious to you is obvious to you.” Before the age of 2, babies do plenty of things parents would rather them not do. But after the age of 2, small children will do things because their parents don’t want them to.
  - This stage is simply the natural extension of a sophisticated research program begun at birth. You push the boundaries of people’s preferences, then stand back and see how they react. Then you experiment, pushing them to their limits over and over again to see how stable the findings are