the scientific study of the brain.
is a new science. Previously the brain was studied by neurologists who
are basically doctors of medicine who specialize in the brain. When non
medical scientists started to study the brain to understand how it
functions, instead of how to treat people who have brain disorders,
neuroscience and neuroscientists came into being.
Brain rules are a way of simplifying some the complex functioning of
our brains. This way of attempting to distill what we know
about the brain and how it relates to learning was inspired by By John
Medina's idea of brain rules as presented in his book of the same name.
Here, this site attempts to cover a similar range of information. In
doing this, this site tries to answer two slightly different but
connected questions. "What can be done to optimize the brain's
functioning?" & "How do various parts of the brain function
when optimized for learning and what conditions have positive and
negative value for that functioning?"
Brain wiring and
In his book
"Brain Rules" John Medina tells us that Eric Kandel is the scientist mostly
responsible for figuring out a lot of what happens in the brain when
learning takes place. He says:
showed that when people learn something, the wiring in their brain
changes. he demonstrated that acquiring even simple pieces of
information involves the physical alteration of the structure of the
neurons participating in the process. Taken broadly, these physical
changes result in the functional organization and reorganization of the
brain. This is astonishing. the brain is constantly learning things, so
the brain is constantly rewiring itself."
Given that this rewiring is taking place all the
time it seems unlikely that any of this wiring would turn out to be
close to being the same in any two brains and this has in fact proved
to be the case even with identical twins who experience the same
environment. Medina says:
"Even identical twins do not have identical brain
wiring. Consider this thought experiment: Suppose two adult male twins
rent the Halle Berry movie Catwoman... Even though they are in the same
room sitting on the same couch, the twins see the movie from slightly
different angles. We find that their brains are encoding visual
memories of the video differently, in part because it is impossible to
to observe the video from the same spot.
...One of the twins earlier in the day read a
magazine story about panned action movies, a picture of Berry figuring
prominently on the cover. While watching the video, this twin's brain
is simultaneously accessing memories of the magazine. We observe that
his brain is busy comparing and contrasting comments from the text with
the movie and is accessing whether he agrees with them. The other twin
has not seen the magazine so his brain is not doing this. Even though
the difference may seem subtle, the two brain are creating different
memories of the same movie.
...Not even identical twins having identical
experiences possess brains that wire themselves exactly the same way.
And you can trace the whole thing to experience.
...Given these data, does it make any sense to have
school systems that expect every brain to learn like every other?
The multiple intelligences movement.
Howard Gardner is a professor of cognition and education and has a
theory of multiple types of intelligence. But following from the idea
that every brain being wired differently any neuroscientist would
insist that there not just nine categories of intelligence but are
probably billions of types of intelligence. Be that as it may Gardner's
influence in education has to be seen as a positive force in making
some allowances for students to learn in different ways.
Evolve & survive. Like every other part of us,
our brains have evolved over time. Our brain can in fact be divided
into three structures corresponding with different periods in our
The lizard brain.
Our ancestors, before we were humans, once had only what is called a
"lizard brain". This brain pretty much only deals with automatic or
housekeeping functions like breathing, keeping us balanced, keeping our
heart beating at the rate needed for whatever we are doing, reacting to
stimuli and refining our movement. This is basically what is called the
brain stem which includes the small brain like structure at the back of
the brain, the cerebellum. Any fairly complex creatures including
lizards have a brain similar to this. We humans also have this lizard
type brain, but on top of it is perched a far more complex structure.
The mammalian brain.
As we evolved into more intelligent creatures, more brain features were
added giving us the brain of a mammal like a cat's. These new features
of the brain deal with long term memory, emotions, refined processing
of sensory information and more complicated understanding. Creatures
with this type of brain are far more intelligent, better informed, have
better memories and are guided by emotions. Humans have this collection
of structures as well as the lizard brain, but unlike most mammals they
have something extra on top of this.
The human brain. Above
the mammalian brain there is a thin layer of jell-o known as the
cortex, the third and most powerful, "human" brain. This brain is
concerned with even better long term memory and even more complex
processing. And a special new section expanded in the front of the
brain called the prefrontal lobes is concerned with inhibiting
emotional responses so a more logical processing can override. This
logical processing called symbolic reasoning is a uniquely human talent.
problem with these three brains is that they developed to do one thing,
and are now being used to do something else. Not only that, but what
one is trying to accomplish, the others are often at odds with, and are
trying to accomplish something else. Far from being a finely tuned
instrument designed to do exactly what it should, the human brain is a
massive kludge at cross purposes with its own other parts. Thus
symbolic reasoning may direct us to go one way but our emotions may be
directing us to do something else. Sometimes our senses tell us one
thing but reasoning tells us something else. It would be nice to have
conscious control over the primitive brain's housekeeping functions,
but we do not.
the fact that our brain is faulty and misfires it still gave us a huge
advantage that was not available to any other creature on earth. After
we were forced from the trees to the Savannah when climate swings
disrupted our food supply, radically new skills were required in order
for us to survive. There were many new problems to solve. Many creature
could not solve such problems and died off. Fortunately for us, going
from four legs to two to walk on the Savannah freed up energy for us to
develop complex brains. These newly evolved brains were better able to
solve new problems as they arose, and those with the more primitive
brains couldn't compete. Humans became the most adept creatures at
surviving by developing a brain that could adapt to change itself.
fitness, novel learning & the prevention of brain deterioration.
In his book
Brain that Changes Itself" Norman Doidge tells us how Fred 'Rusty' Gage, of the
Salk Institute at La Jolla California performed
an experiment with rats that showed that the ones that were put in a
novel environment that required new learning responded with the
activation of neurogenesis in their hippocampus which he found to have
a 15 percent increase in volume. Doidge explains about tests then
conducted on older mice:
"When the team tested older mice raised in
the enriched environment for ten months in the second half of their
lives, there was a five fold increase in the the number of neurons in
the hippocampus. These mice were better at tests of learning,
exploration movement and other measures of mouse intelligence than
those raised in unenriched conditions. They developed new neurons,
though not quite as quickly as younger mice, proving that long-term
enrichment had an immense effect on promoting neurogenesis in an aging
Many people picked up on the fact the most
effective contributor to increased proliferation of new neurons was the
running wheel. They pointed out that this was exercise and that perhaps
exercise was the factor that induced the neuron proliferation. But n
"The Brain that Changes Itself" Doidge explains that Gage
himself had other
"Gage's theory is that in a natural
setting, long-term fast walking would take the animal into a new and
different environment that would require new learning, sparking what he
calls 'anticipatory proliferation.'
'If we lived in this room only,' he told me, 'and
this was our entire experience, we would not need neurogenesis. We
would know everything about this environment and could function with
all the basic knowledge we have.'
This theory that novel environments may trigger
neurogenesis, is consistent with Merzenich's discovery that in order to
keep the brain fit, we must learn something new, rather than simply
replaying already mastered skills.
But as we have said, there is a second way to
increase the number of neurons in the hippocampus: by extending the
life of neurons that are already there. Studying mice the team found
that learning how to use the other toys, balls, and tubes didn't make
new neurons, but it did but it did cause the new neurons in the area to
live longer. Elizabeth Gould also found that learning, even in a
nonenriched environment, enhances survival of stem cells. thus physical
exercise and learning work in complementary ways: the first to make new
stem cells, the second to prolong their
In his book
"The Brain that Changes Itself" Norman Doidge has the
following to say about Merzenich:
"Merzenich thinks our neglect of intensive
learning as we age leads the systems in the brain that modulate,
regulate and control plasticity to waist away."
was found to have an application for helping people avoid Alzheimer's
disease. For instance, studying a musical instrument or learning a new
dance, (activities that require concentration) appeared to be to be
particularly effective in warding off Alzheimer's disease. It was found
that the most effective method of improving brain function was learning
new things and particularly new skills. This approach has been shown to
be successful in the work of Michael
Merzenich and others. Doidge continues:
"As Merzenich's work has shown, however, a
condition often confused with Alzheimer's disease, and much more common
- age related memory loss, a typical decline in memory that occurs in
advanced years - seems almost certainly reversible with the right
mental exercises." [These are mental exercises involving learning
new skills that Merzenich provides through his work at Fast Forward.]
"Train Your Mind Change Your Brain" Sharon Begley also speaks
about Merzenich's work as follows:
a study Merzenich presented in late 2005, he had elderly volunteers,
sixty-one to ninety-four years old, undergo eight weeks of computer
based training to improve the brains ability to discern the sounds of
speech. ...'The majority improved ten or more years of neurocognitive
status.' says Merzenich.
foresees a day when the discoveries of neuroplasticity will usher in 'a
brain-fitness culture,' reflecting 'an understanding that you need to
exercise your brain as you exercise your body.
adults are frequently told that, to keep their mind sharp, they need to to
stimulate it with activities such as crossword puzzles and reading. But
such activities done repeatedly become second nature, demanding less
attention than new skills do.
Merzenich and colleagues point out, animal studies have shown
'that under optimal environmental conditions, almost every physical
aspect of the brain can recover from age related losses.' New neurons
can bloom; gray matter can become thicker. Neuroplasticity makes it
have been many studies in related areas such as those related below in
the new scientist. Please note that all the conditions mentioned below,
as helping prevent mental deterioration in old age, are all conditions
that are likely to involve continuing extensive new learning.
"Study after study has shown that intelligence,
good education, literacy and high status jobs all seem to protect
people from mental ravages of old age and provide some some resistance
to the symptoms, if not the brain shrinkage, of dementia." New
Exercise and brain fitness. Neuroscientists
have also discovered the brain was also capable of being helped by any
kind of intense activity such as exercise. Good exercise, it was found,
sent more oxygen to the brain and stimulated the sensory and motor
cortexes. John Medina, in his book
"Brain Rules" explains some of this:
you exercise, you increase blood flow across the tissues of your body.
This is 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. This allows more access to the
bloodstream's goods and services, which include food distribution and
waste disposal. [The main function of oxygen in the blood is
to act like an efficient electron-absorbing sponge.] [The oxygen rich
air you inhale keeps the food you eat from killing you.] The
more you exercise, the more tissues you can feed and the more toxic
waste you can remove. this happens all over the body. this is why
exercise improves the performance of most human functions...
same happens in the human brain. Imaging studies have shown that
exercise literally increases blood volume in a region of the brain
called the dentate gyrus. That's a big deal. The dentate gyrus is a
vital constituent of the hippocampus, a region deeply involved in
memory formation This blood-flow increase, which may be the result of
new capillaries, allows more brain cells greater access to the blood's
food and haz-mat teams.
brain-specific effect of exercise is recently has become clear... At
the molecular level, early studies indicate that exercise also
stimulates one of the brain's most powerful growth factors, BDNF. this
stands for Brain Derived Neurotropic Factor, and it aids in the
development of healthy tissue. BDNF exerts a a fertilizer-like growth
effect on certain neurons in the brain. The protein keeps existing
neurons young and healthy, rendering them much more willing to connect
with another. It also encourages neurogenesis, the formation of new
cells in the brain. The cells most sensitive to this are in the
hippocampus, inside the very regions deeply involved in human cognition.
Neuroscience and social
psychology have shown that what goes into both short-term memory and
long-term memory, and our ability to recall it, is completely dependent
on our attending to it. These sciences have established that very
little in the way of information gets through to our brains if we do
not pay attention to it. John Medina, in his book
"Brain Rules" explains that there are many way in which our
attention cane be engaged or hijacked:
years ago, a scientist by the name of Michael Posner derive a theory of
attention that remains popular today. ...Posner hypothesized that we
pay attention to things because of the existence of three separable but
fully integrated systems in the brain. ...In Posner's model, the brains
first system functions much like the two-part job of a museum security
officer: surveillance and alert. He called it the Alerting or
Arousal Network. It monitors the sensory environment for any unusual
activities. This is the general level of attention our brains are
paying to the world, a condition termed Intrinsic Alertness.
the alarm, we orient ourselves to the attending stimulus, activating a
second network. We may turn our heads toward the stimulus, perk up our
ears, perhaps move toward (or away) from something. ...The purpose is
to gain more information about the stimulus, allowing the brain to
decide what to do. Posner termed this the Orienting Network.
third system, the Executive Network, controls the 'oh my gosh what
should I do now' behaviors. These include setting priorities, planning
on the fly, controlling impulses, weighing the consequences of our
actions, or shifting attention."
emotions can hijack our attention. When strong emotions are involved we
do not have control of our attention. We involuntarily attend to the
stimulus or the event. Learning is made easier by emotional content
because we automatically attend to it.
we are in a learning situation we may wish to maintain our attention on
what ever is being presented in the lesson. We can force our attention
on some event in this way but research has found our ability to do this
tends to quickly fade after about ten minutes. This can be brought back
if some emotional element is injected into the lesson such as a
surprise or humor making available another ten minutes.
is inextricably linked to attention and can help us maintain our
attention beyond the usual ten minutes. Interest and importance can
cause the initial attention to be stronger and last longer.
are continually taking in masses of information through our senses but
most of it we are never aware of because we are not paying attention to
it. We rely on Posner's alerting network to uncover anything
interesting or important so we can be aware of it.
Sleep and dreams. Sleeping and Dreaming turn out to be of major
importance to learning. They are so important that this section grew so
large as to require a separtate page, which can be accessed by clicking here.
Like sleep, stress
seems to be deeply tangled in the learning experience. Firstly we know
that any experience that is associated with a highly emotional state
will make that experience more memorable. We have strong persistent
memories of things that make us angry and afraid. At school teachers
try to take advantage of this by making students afraid so they will
remember. As will become clear from the research results explained
below this strategy if continued for any length of time will become
highly counter productive. These strong emotions like anger and fear
activate the fight or flight orienting system which floods the body and
brain with strong chemicals. Initially the body is flooded with
adrenaline which causes your pulse to race and your blood pressure to
rise and releases energy to muscles ready to perform any action
quickly. Your body prepares to go into overdrive, it is stressed. There
is however another hormone at work in this situation. This chemical is
called cortisol. This hormone's function is to return the body to a
normal state lowering the pulse, restoring blood pressure to normal and
calming and relaxing the muscles. In his book
"Brain Rules" John Medina explains:
do our bodies need to go through all this trouble? The answer is very
simple. Without a flexible, immediately available, highly regulated
stress response, we would die. Remember, the brain is the world's most
sophisticated survival organ. All of its many complexities are built
toward a mildly erotic singularly selfish goal: to live long enough to
thrust our genes on the next generation. Our reactions of
serve the live-long-enough part of that goal. Stress helps us manage
the threats that could keep us from procreating.
survival issues we faced in our first few million years did not take
hours or even a minute, to settle. The saber-toothed tiger either ate
us or we ran away from it - or a lucky few might stab it, but the whole
thing was over in under a minute. Consequently, our stress responses
were shaped to solve problems ha lasted not for years, but for seconds.
They were primarily designed to get our muscles moving us as quickly as
possible, usually of harms way. You can see the importance of this
immediate action by observing people who cannot mount a thorough and
sudden stress response. If you had Addison's disease, for example you
would be unable to to raise your blood pressure in response
to severe stress, such as being attacked by a mountain lion. Your blood
pressure would drop catastrophically, probably putting you into a state
of debilitating shock. You would become limp, then you would become
days, our stresses are measured not in moments with mountain lions, but
with hours, days, and sometimes months with hectic workplaces,
screaming toddlers and money problems. And when moderate amounts of of
hormone build up to large amounts, or when moderate of hormone hang
around too long, they become quite harmful."
call the state, that animals and humans reach when confronted with
severe stress from which there is no escape, learned helplessness. All
animals including humans if stressed for long periods without release
tend to lose heart and learn that the only strategy worth attempting is
to do nothing. They literally learn to be helpless. Once a person has
learned to be helpless it becomes nearly impossible to learn anything
else. In order to learn a person must first feel that he can learn. For
more about this see Learning key 9 on choices. Chronic stress also has
other unfortunate consequences all of which impair human ability to
learn. John Medina continues:
the long term,...too much adrenaline stops regulating surges in your
blood pressure. These unregulated surges create sandpaper like rough
spots on the inside of your blood vessels. The spots turn into scars,
which allow sticky substances in the blood to build up there, clogging
your arteries. If it happens in the blood vessels in your heart you get
a heart attack; in your brain, you get a stroke. Not surprisingly
people who experience chronic stress have elevated risk of heart
attacks and strokes.
also affects our immune response. At first, the stress response helps
equip your white blood cells, sending them off to fight on the body's
most vulnerable fronts, such as the skin. Acute stress can even make
you respond better to a flu shot. But chronic stress reverses these
effects, decreasing your number of heroic white-blood cell soldiers,
stripping them of their weapons, even killing them outright.
hippocampus, that fortress of human memory, is studded with cortisol
receptors like cloves in a ham. This makes it very responsive to stress
signals. If stress is not too severe, the brain performs better. Its
owner can solve problems more effectively and is more likely to retain
information. There is an evolutionary reason for this. Life-threatening
events are some of the most important experiences we can remember. they
happen with lightening speed in the Savannah, and those who could
commit those experiences to memory the fastest (and recall them
accurately with equal speed) were more apt to survive than those that
couldn't. Indeed research shows that memories of stressful experiences
are formed almost instantaneously in the human brain, and they are
recalled very quickly during times of crises.
stress is too severe or too prolonged, however, stress begins to harm
learning. The influence can be devastating. You can see the effects of
stress on learning in everyday life. Stressed people don't do math very
well. They don't process language very efficiently. They have poorer
memories, both short and long forms. Stressed people do not generalize
or or adapt old pieces of information to new scenarios as well as non
stressed individuals. They can't concentrate. In almost every way it
can be tested chronic stress hurts our ability to learn.
...Specifically, stress hurts declarative memory (things you can
declare) and executive function (the type of thinking that involves
problem solving). Those of course, are the skills needed to excel in
school and business."
We do not see with
our eyes we see with our brains. Because vision is by far our
most dominant sense, taking up half of our brain's resources what we
see often influences what is perceived through any of the other senses.
We tend to taste what we see, smell what we see, hear what we see and
even feel what we see. Even our balance organs will provide
misinformation if we see the world the wrong way. Food tends to taste
better when it looks appetizing. Wine smells sweeter when it is a
beautiful deep rich red color. We are used to thinking of what we see
as being completely reliable as though our eyes work like a camera
recording exactly what is there. We say, "Seeing is believing."
Unfortunately this is quite wrong and our eyes are simply not 100
percent trustworthy. The reason why this is so, is that the visual
analysis our brains perform has many steps. The retina assembles
photons into little movie-like streams of information. These streams on
entering the brain are analyzed and information is broken up into
various discrete types of conceptual data and sent to various brain
areas for various types of processing. For instance motion is perceived
quire separately from color and outlines, shadows and depth are all
processed separately and then recombined.
learn and remember best through pictures, not through written or spoken
words. John Medina in his book
"Brain Rules" has this to say:
it comes to memory, researchers have known for more than 100 years that
pictures and text follow very different rules. Put simply, the more
visual the input becomes, the more likely it is to be recognized - and
recalled. The phenomenon is so pervasive, it has been given its own
name: the pictorial superiority effect, or PSE.
PSE is truly Olympian. Test performed years ago showed that people
could remember more than 2,500 pictures with at least 90 percent
accuracy several days post exposure. even though subjects saw each
picture for about 10 seconds. Accuracy rates a year later still hovered
around 63 percent. In one paper - adorably titled 'Remember Dick and
Jane?' - picture recognition information was reliably retrieved several
throughout these experiments were comparisons with other forms of
communication. The favorite target was usually text or oral
presentations, and the result was 'picture demolishes them both.' It
still does. Text and oral presentations are not just less efficient
than pictures for retaining certain types of information; they are way
less efficient. If information is presented orally, people remember
about 10 percent, tested 72 hours after exposure. That goes up to 65
percent if you add a picture.
inefficiency of text has received particular attention. One of the
reasons that text is less capable than pictures is that the brain sees
words as lots of tiny pictures. Data clearly show that a word is
unreadable unless the brain can separately identify simple features in
the letters. Instead of words we see complex little art-museum
masterpieces, with hundreds of features embedded in hundreds of
letters. Like an art junkie, we linger at each feature, rigorously and
independently verifying it before moving to the next...
with hindsight, we could have predicted such inefficiency. Our
evolutionary history was never dominated by text-filled billboards of
Microsoft Word. It was dominated by leaf-filled trees and saber-toothed
tigers. The reason vision means so much to us may be as simple as the
fact that most of the major threats to our lives in the Savannah were
apprehended visually. Ditto with most of our food supplies. Ditto with
our perceptions of reproductive
most teaching is composed of presenting information through lecturing,
writing on a board, or through reading assignments. John Medina
should learn why pictures grab attention. Educators should
know how pictures transfer information. There are things we know about
how pictures grab attention that are rock solid. We pay lots of
attention to color. We pay lots of attention to to orientation. We pay
lots of attention to size. And we pay special attention if the object
is in motion. Indeed most of the things that threatened in the
Serengeti moved, and the brain has evolved unbelievably sophisticated
trip-wires to detect it. We even have specialized regions to
distinguish when our eyes are moving versus when the world is moving.
These regions routinely shut down perceptions of eye movement in favor
of the environmental movement.
should use computer animations. Animation captures the
importance not only of color and placement but also motion. With the
advent of web-based graphics, the days when this knowledge was optional
for educators are probably over. Fortunately, the basics are not hard
to learn. With today's software, simple animations can be created by
anybody who knows how to draw a square and a circle. Simple
two-dimensional pictures are quite adequate; studies show that if the
drawings are too complex or lifelike, they can distract from the
transfer of information."
Gender. Male and female brains are different, but the
question is why? What appears to be significant statistical differences
between male and female brains may not be inevitably determined, but
rather may be well within our ability to control. 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. Woman 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 those
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. Men tend to be more hierarchically competitive, to
establish a pecking order, while women tend to fall into the me too
type of competition to establish inclusion.
while there may actually be different genetic predispositions in men
and women that may play a part in whether male or female brains turn
out different or not, it is now known that this is not a full analysis
of what happens. We now know that genes, far from being a template that
will determine our qualities and abilities is far more like a control
board that is operated by environmental influences. Genes have to be
switched on, switched off, turned up, or turned down. Thus the
differences between males and females like any kind of human difference
may be diminished or exaggerated by environmental conditions. This is
possible especially through the actions of other people and through our
own actions in choosing those environmental conditions and placing
ourselves in them.
are two social forces at work here widening or shrinking these
differences between men and women. Firstly, there is imitation and
conformity where we tend to act like our role models and we tend to
want to be like others we see around us in order to fit in. Secondly,
we tend to become what is expected of us. This is what sociologist
Robert Merton calls a self fulfilling prophecy. People believe that men
act this way and women act that way so that is how we act. Thus boys
tend to try and act like men and girls tend to try and act like women.
We are drawn to act more and more like our stereotype. We see the path
through our lives as being easier and more enjoyable if we will just
embrace our stereotype. So we do. In this way society and ourselves
become complicit in deciding whether the brain differences of men and
women are large or small, exist or do not exist.
instance, it has been shown in many often repeated experiments that
women are significantly better at languages than men, but this may be
because they practice speaking more. The more women practice talking
the better their verbal skills become and the more the areas in their
brains concerned with language tend to grow. Our brains are so plastic
that it may be possible for men and women to develop very similar
brains, given the right environment, despite staring off to have
genetic predispositions to produce very different brains. In his book
"Brain Rules" John Medina tells how his son's teacher managed
to forestall a widening gender gap in his son's class:
son's third-grade teacher began seeing a stereotype that worsened as
the year progressed. The girls were excelling in the language arts and
the boys were pulling ahead in math and science. This was only the
third grade! The language-arts differences made some sense to her. But
she knew there was no statistical support for the contention that men
have a better aptitude for math and science than women. Why for
heaven's sake was she presiding over a stereotype?
teacher guessed that part of the answer lay in the student's social
participation during class. When the teacher asked a question of the
class, who answered first turned out to be unbelievably important. In
the language arts, the girls inevitably answered first. Other girls
reacted with that participatory, 'me too' instinct. The reaction on the
part of the boys was hierarchical. The girls usually knew the
answers, the boys usually did not, and the males responded by doing
what low-status males tend to do: They withdrew. A performance gap
quickly emerged. In math and science, boys and girls were equally
likely to answer a question first. But the boys used their familiar
'top each other' conversational styles when they participated,
attempting to establish a hierarchy based on knowledge aptitude. This
included drubbing anyone who didn't make the top, including the girls.
Bewildered, the girls began withdrawing from participating in the
subjects. Once again a performance gap emerged.
teacher called a of the girls and verified her observations. She then
asked for a consensus about what they should do. The girls decided that
they wanted to learn math and science separately from the boys.
Previously a strong advocate for mixed gender classes, the teacher
wondered aloud if that made any sense. yet if the girls started losing
the math-and-science battle in the third grade, the teacher reasoned
they were not likely to excel in the coming years. She obliged. It took
only two weeks to close the performance gap."
experiment does not provide much in the way of good science. It does
however, point out a direction to be investigated. It may well be that
we can do much to prevent the widening of mental differences between
males and females if we so
Exploration as a way of
being prepared. The human brain is large with cognitive
abilities that give humans tremendous advantage over all the other
animals. What are those advantages and how do they develop? The main
way humans have an advantage over other animals is by being prepared in
advance for any situation that might come up. Our large brains have
both a capacity to hold vast amounts of information and an amazing
capacity to process that information quickly into solutions to any
problem that might occur.
The pleasure mechanism.
Learning and the pleasure mechanisms in the brain are deeply entangled.
We now know that the neurotransmitter dopamine seems to be the main
source of what we call pleasure. But dopamine does not act in the
simple manner that it was once thought it. Dopamine does not simply
flood the system in response to a reward or the achievement of a goal.
If it did the amount of dopamine would be proportional to the reward or
the achievement of that goal each time it was obtained. This is not the
case. Dopamine is far greater in our system when we are learning
something and greatest when we are just beginning to learn something.
Dopamine is greatest in our systems when we first notice the
possibility of a pattern emerging where we might get a reward or we
might achieve a goal.
pleasure is greatest when the likelihood of getting a reward or
achieving a goal is most shaky. It is now thought that this means that
the pleasure is not the result of a reward or achievement but rather
the result of a learning possibility. It is now thought that the
function of pleasure is to focus attention on such possibilities so
that learning takes place. Pleasure then occurs not in response to a
reward or an achievement, but in response to weak anticipation of a
reward or achievement. Why weak anticipation and not strong
anticipation? It is simple. When anticipation is strong learning has
already taken place, we know something will happen. As soon as we know
something in this way the brain no longer has to draw our attention to
it. We already know it. When we are not sure, we only have a hunch or a
weak conjecture, so our brain lets us know we have to take notice of
what happens so we can learn. In his paper " Dopamine Neurons Respond"
Wolfram Schultz put it like this:
neurons respond to primary rewards only when the reward occurs
unpredictably. ...By contrast, a fully predicted reward does not elicit
a response in dopamine neurons."
reason for our brains to focus our attention like this is so that we
will have a predisposition to learn acting in our brains continually
throughout our lives. Unfortunately this mechanism can malfunction in
several ways. The most obvious way it can malfunction is drugs. Certain
drugs can cause the system to flood with dopamine. When this happens
our brain is tricked. A part of the brain has the illusion it is
learning something, when it is not. It tries to correct this
malfunction by reducing the amount of dopamine in response to the drug.
This response is what we know as addiction where ever increasing
amounts of the drug are needed to get the same pleasure.
also fools this pleasure mechanism. The gambler sees endless possible
patterns which he uses to anticipate a reward, and the uncertainty of
the reward causes the brain to flood itself with dopamine to focus
attention. Unfortunately the patterns in gambling are an illusion where
we are fooled by randomness. Again we learn nothing, and we lose money
while we do it, but we do get the pleasure of uncertainty or
When the pleasure
mechanism works well. When the pleasure mechanism is working
well, it enables us to have a predisposition to know things, not just
when they are needed to get us out of a jam like when a saber tooth is
running us down, but in advance. Having a large store of knowledge
allows two very important brain functions to effectively give us this
advantage. We can preprocess the knowledge into plans and scenarios for
dealing with possible problems before the occur, and we can also
process the knowledge on the fly more easily solving problems as they
occur. In this way we may avoid the saber tooth all together, or deal
with him quickly and effectively when he appears.
Curiosity and the aggressive
desire to explore.
Our brains manage
this tremendous feat of collecting information in advance of the need
for it, by means of curiosity and the predisposition to explore our
environment and learn about it. This is a direct outcome of the brain's
pleasure mechanism. We are not the only animals that are curious, but
our bigger more efficient brains allow us to make better use of it. In
"Brain Rules" John Medina tells us he considers this
accumulation of masses of information as being the fueling of the
brain which keeps our intellect running. He says:
fuel consists of a clear, high octane, unquenchable need to know.
Babies are born with a deep desire to understand the world around them
and an incessant curiosity that compels them to aggressively explore
it. This need for explanation is so powerfully stitched into their
experience that some scientists describe it as a drive just as hunger
and thirst and sex are drives.
seem preoccupied by the physical properties of objects. babies younger
than a year old will systematically analyze an object with every
sensory weapon at their disposal. they will feel it, kick it, try to
tear it apart, stick it in their ear, stick it in their mouth, give it
to you so you can stick it in your mouth. They appear to be intensely
gathering information about the properties of the object. Babies
methodically do experiments on the objects to see what else they will
testing like that is the way all babies gather information. They use a
series of increasingly self-corrected ides to figure out how the world
works. They actively test their environment, much as a scientist would:
Make sensory observation, form a hypothesis about what is going on,
design an experiment capable of testing the hypothesis, and then draw
conclusions from the findings.
little ones, discovery brings joy. Like an addictive drug, exploration
creates the need for more discovery so more joy can be experienced. it
is a straight-up reward system that, if allowed to flourish, will
continue into the school years. As children get older, they find that
learning not only brings them joy, but it also brings them mastery.
Expertise in specific subjects breeds confidence to take intellectual
[sometimes with the right mindset]. If these kids don't end up
in the emergency room, they may end up with a Nobel Prize.
believe it is possible to break this cycle, anesthetizing both the
process and the child. By first grade, for example children learn that
education means an A. They begin to understand that they can acquire
knowledge not because it is interesting, but because it can get them
something. Fascination can become secondary to 'What do I need to know
to get the grade?' But I also believe the curiosity instinct is so
powerful that some people overcome society's message to go to sleep
intellectually and they flourish anyway.
grandfather was one of those people. He was born in 1892 and lived to
be 101 years old. He spoke eight languages, went through several
fortunes, and remained in his own house (mowing his own lawn) until the
age of 100, lively as a firecracker to the end. At a party celebrating
his centenary, he took me aside. 'You know Juanito,' he said clearing
his throat, 'sixty-six years separate the Wright brothers' airplane
from Neil Armstrong and the moon.' He shook his head, marveling. 'I was
born with the horse and buggy. I die with the space shuttle. What kind
of thing is that?' His eyes twinkled. 'I live the good life!' He died a
Medina also explains that the human brain of an adult is capable of
experiencing the same joy that young children get from learning and
thus humans can experience this joy throughout their lives. Humans can
do this because our brains, while not being as plastic as a baby's, are
nevertheless capable of massive new growth throughout the human
lifetime. John Medina says: "Researchers have now shown that
some regions of the adult brain stay as malleable as a baby's brain, so
we can grow new connections, strengthen existing connections, and even
create new neurons, allowing all of us to be lifelong learners." The
proof of this was brought home to Medina when he worked as a post-doc
at the University of Washington. He explains as follows:
1992, Edmond Fischer shared with Edwin Krebs he Prize in Physiology or
Medicine. I had the good fortune to be familiar with both their work
and their offices. They were just down the hall from mine. By the time
I arrived, they were already in their mid-70. The first thing I noticed
upon meeting them was that they were not retired. Not physically an no
mentally. Long after thy had earned the right to be put out to
scientific pasture, both had powerful, productive laboratories in full
swing. Every day I would see them walking down the hall, oblivious to
others, chatting about some new finding, swapping each other's
journals, listening intently to each other's ideas. Sometimes they
would have someone else along, grilling them and in turn being grilled
about some experimental result. They were creative like artists, wise
as Solomon, lively as children They had lost nothing."
The right stuff learning
environment. It is plain that we all start out with this
motivating joy of learning and that some of us seem to retain it into
old age. Most of us however seem to lose this joy of learning and it
seems likely that the environment in which we dwell could be improved
so this does not happen. There are many ways people could go about
improving the environment so that this joy could be kept alive. Most of
these ways involve others providing time and resources to encourage
interest when it occurs and exposing young people to new ideas and in a
ways that make it interesting. John Medina's description of his early
learning environment is a perfect example of what can be done. He says:
remember when I was 3 years old, obtaining a sudden interest in
dinosaurs. I had no idea that my mother had been waiting for it. That
very day, the house began its transformation into all things Jurassic.
And Triassic. And Cretaceous. Pictures of dinosaurs would go up on the
wall. I would begin to find books about dinosaurs strewn on the floor
and sofas. Mom would even couch dinner as 'dinosaur food,' and we would
spend hours laughing our heads off trying to make dinosaur sounds. And
then suddenly, I would lose interest in dinosaurs, because some friend
at school acquired an interest in spaceships and rockets and galaxies.
Extraordinarily, my mother was waiting. Just as quickly as my whim
changed, the house would begin its transformation from big dinosaurs to
Big Bang. The reptilian poster came down, and in their places, planets
would begin to hang from the walls. I would find little pictures of
satellites in the bathroom. Mom even got 'space coins' from bags of
potato chips, and I eventually gathered all of them in a collectors
happened over and over again in my childhood. I got an interest in
Greek mythology, and she transformed the house into Mount Olympus. My
interests careened into geometry, and the house became Euclidean, then
cubist. Rocks, airplanes. By the time I was 8 or 9 I was creating my
own house transformations.
day, around age 14, I declared to my mother that I was an atheist. She
was a devoutly religious person, and I thought this announcement would
would crush her. Instead, she said something like 'That's nice, dear,'
as if I had just declared I no longer liked nachos. The next day, she
sat me down by the kitchen table, a wrapped package in her lap. She
said calmly, 'So I hear you are now an atheist. Is that true?' I nodded
yes, and she smiled. She placed the package in my hands. 'The man's
name is Friedrich Nietzsche, and the book is called "Twilight of the
Idols," she said. 'If you are going to be an atheist, be the best one
out there. Bon appetit!' I was stunned. But I understood the message.
Curiosity itself was the most important thing. And what I was
interested in mattered. I have never been able to turn of this fire
hose of curiosity."
Another way in which we have an advantage over other animals is our
ability to cooperate. One way this cooperation is accomplished is by
out brains capacity to communicate, which in turn depends on our
ability to develop a complex verbal language that makes such
communication possible. Complex language in turn depends on our brain's
great ability for both object recognition and its ability for symbol
recognition and manipulation.
way this cooperation is made possible is by our facility for mind
reading or being able to put ourselves in the bodies of others and feel
feel. Our brains have a much larger capacity than other animals for
both, empathy and predicting the actions of others.
another way humans have an advantage over other creatures is our large
brain's ability to prepare motor plans in advance which can be used
instantly to solve problems and get us out of trouble as it
are discovering new things about the changeability of the brain all the
time, and one of the newest and most exciting discoveries to emerge
recently is the discovery of mirror neurons. Giacomo Rizzolatti working
with his team of neuroscientists in Parma Italy were first to notice
these unusual neurons. Basically mirror neurons are neurons that become
electrically active both when a subject is performing an action and
when the subject is seeing the same action performed. Rizzolatti and
his team were experimenting with macaque monkeys. They had implanted
electrodes into the motor areas of they monkey's brains and connected
these to computers so the could see and hear the discharge of motor
neurons during grasping exercises. Between these exercises while the
monkey was still, one of the team, Vittorio Gallese, was moving about
the room. He reached out to grasp something and heard a burst of
activity from the computer as if the monkey was grasping something. But
the monkey, when he looked, was quite still.
Mirroring People. In
"Mirroring People" Marco Iacoboni lays out the investigation
of these neurons. Although this work is recent and still needs some
checking, a picture is emerging as to just what the functions of these
mirror neurons might be. One of the first experiments to be performed
in this investigation was the checking of the firing patterns of
neurons in a monkey's brain, when it was picking up fruit and eating it
and picking it up and putting it in a bowl. This was then checked
against the same monkey simply watching a human perform the same
actions. The results were conclusive. When watching or performing an
action most of the same neurons fired yet they fired differently for
the two different actions.
The functions of mirror neurons. It seems likely from the
experiments done on mirror neurons so far, and as reported by Marco
Iacoboni, that mirror neurons have several functions:
plans. Mirror neurons seem to represent what Piaget would
have called schemas. These are sort of motor plans for specific
actions, that are simulated in the mind ready to put into action. The
motor plan is active, and a readiness exists for the action to be
performed. We see somebody picking up an apple and eating it, and those
motor plans are activated in our own mind preparing us to pick up an
apple and eat it our self. This happens instantaneously. There is no
intervening thought. Thought comes after this, in deciding whether or
not to perform the action.
recognition. Mirror neurons also fire in response to seeing
objects, especially ones that could be involved in an action. It is
likely, that objects gain part of their meaning from the actions they
could be involved with. The sight of the object would therefore
activate the motor plans likely to be involved with that object. We see
the apple and the motor plans for picking it up and eating it are
automatically simulated in our minds, as part of what we understand an
apple to be.
recognition. Images, words and other symbols used in
communication readily invoke the activation of mirror neurons. Visual
representation of an action activates the mirror neurons for that
action. But so do auditory representations of the action, or verbal
descriptions of the action. Mirror neurons are probably activated just
by thinking about some action. Thus we are not surprised to find that a
drawing of a ball being kicked, the sound of a ball being kicked,
hearing somebody say kick, or thinking about kicking all activate the
mirror neurons that would be used in the action of kicking a ball.
the actions of others. Mirror neurons also appear to be
involved in predicting the intentions of others. Reaching for a certain
object by one person, by virtue of the activation of mirror neurons,
begins the process in another person of simulating motor plans.
Obviously, an object could have more than one motor plan as part of its
meaning. To be effective in activating the correct motor plan, clearly
other factors had to be accessed in observing the other person, to
invoke the correct motor plan. It was found that mirror neurons were
sensitive to contextual situations, facial expressions and other cues
to a person's emotional state.
Mirror neurons were also found to enable people to feel what other
people were feeling. When mirror neurons were activated though
observation of another person's face etc. it was found that this also
activated the emotional firing pattern of neurons in the limbic system.
This firing pattern of neurons closely matched the emotional state in
the other person's limbic system. The limbic system is the part of the
brain that deals with emotion. These two areas of the brain, the facial
recognition mirror neurons and the limbic system, were found to be
directly linked together through an area of the brain called the
insula. The extent and strength of these mirror neuron firings were
found to correlate nicely with empathic ability. Also the ability to
recognize the facial expressions of others correlates with general
social competence. It was also found that a week or damaged mirror
neuron system was a good indicator of autism.
The development of
mirror neurons. Some ability to mimic rudimentary manual and
facial gestures were shown by Andrew Meltzoff to exist in newborn
babies just after birth and thus could be said to be inborn or
instinctual. Clearly then some mirror neurons must exist for this
function at birth. However experimentation has shown that most mirror
neurons come into existence through seeing some action performed and
trying to imitate it. Mutual imitation of parent and child, it would
seem, is what enables mirror neurons to form. When the action has been
learned new mirror neurons have been formed. These mirror neurons are
the ones that simulate the new action. Thus clearly learning any skills
must involve the forming of new mirror neurons. In all probability, the
formation of new mirror neurons may be a part of any kind of learning.
The functions of mirror neurons confirm that the actions people perform
have much more to do with what we perceive others doing, than what we
are told or told to do. Our brains simply function that way.
Another line of research in neuroscience concerns the study of white
matter in the brain. In the brain, white matter is composed of bundles
of myelinated nerve
cell processes (or axons). These connect various gray matter areas (the
locations of nerve
cell bodies) of the brain to each other, and carry nerve impulses
These connecting nerve fibers or axons are wrapped in a dense fat
called myelin which prevents the electrical impulses leaking out of
those axons. This wrapping takes place in two different ways. In the
brain and the spinal cord this wrapping is carried out by cells called
oligodendrocytes that extend tentacle like arms to wrap several axons
and give those axons a bumpy unsmooth appearance. In the nerve fibers
that spread out to every part of our bodies whole cells called schwann
cells wrap themselves completely around the axons in sections that give
the appearance of sausages. Although the study of myelin is in its
infancy some of the new theories about the function of myelin are very
much concerned with learning and tend to corroborate and explain much
of the work sited above.
clearer more accurate. For instance it is now fairly well
accepted that the wrapping of nerve fibers in myelin speeds up the
electrical impulses traveling along them and by as much as 100 times.
The more myelin that wraps around the fiber the faster it goes. Myelin
also decreases the wait between nerve impulses by a factor of 30. These
two improvements in processing result in an increase in processing
power by as much as 3000 times. Dr. Douglas Fields of the National
Institute of Health in Bethesda Maryland uncovered the mechanism that
causes myelin to wrap around nerve fibers which he describes in a 2006
paper in the journal Neuron. It appears that the supporter cells
(oligodendrocytes and schwann cells) sense nerve firing and respond by
wrapping myelin around the fiber that fires. The more neurons or nerve
fibers fire, the more myelin wraps around it, the faster the signal
studies such as those by Fredric Ullen, Torkel Klingberg and jesus
Pujol have shown an unmistakable increase in in white matter in
response to the learning of any complex skill. It would appear that not
only does myelin wrap, make a nerve impulse much less susceptible to
distortion and faster, but also allows for a much finer control.
Impulse speed is skill.
A single action may involve many neurons and nerve fibers that need to
fire at just the right time, in the right sequence. Two impulses from
different fibers for instance, may need to reach a particular neuron at
approximately the same time for it to fire in turn and thus set up a
sequence. By varying the amount of myelin that wraps around each fiber
control of how fast an impulse may travel and thus determine when it
will arrive at another neuron. In this way a correct sequence my be
obtained by varying the amount of myelin wrapping each fiber. Also an
action in a skill may be varied until you get it right and thereafter
only occasionally practiced and always with an eye to improving it.
Varying actions in this way causes minute changes in the amount of
myelin wrapping various fibers, which likewise is a response to those
fibers firing. This in turn causes the fibers to fire more correctly at
the right time in the right sequence. Thus the action gradually moves
toward being performed perfectly or correctly. Nerve firings grow
myelin, myelin controls impulse speed, and impulse speed is skill.
myelin wraps it does not unwrap. Thus actions as determined by nerve
impulses can be adjusted a little as more and more myelin wraps around
but you are always building on what is already there. Piaget and Maslow
were right. Wiping an action out and relearning it from the beginning
is very difficult to try and do. Old habits die hard.
Age matters for myelin.
Myelin grows more extensively at particular periods in a person's life.
As child development progresses myelin wrapping seems to come in waves
and appears in particular parts of the brain. This may be in response
to genetic triggers or it may be simply in response to to new types of
learning which would not have been possible without other learning
having taken place first. For instance a baby cannot learn to walk
until it can stand up. Also morality cannot even be conceived of until
the idea of cause and effect is understood. In average adults, from the
age of about 50, myelin begins to deteriorate faster than it is
created. This of course depends on the amount of learning being done by
persons over the age of 50. Keeping the mind sufficiently active may
enable the brain to replace myelin as fast or faster than it
Brain Rules. John
Medina, at the end of each chapter in his book, tries to compress the
information in that chapter into a few clear statements or rules. Below
this site has included all those statements of Medina's 12 rules and
included a few others that may be equally as important. Not all the the
information relating to those rules is featured above on this page but
all such information may be reached by clicking on the heading for each
Learning is not one of Medina's rules but it is perhaps the most
important condition for healthy and optimized brain functioning. The
brain's main function is to learn.
is the case with every other body part, if you don't use it you lose
it. The brain is no different in this regard. If parts of it are left
unused they deteriorate or are taken over by competing functions. If
the whole brain is used little it is likely to atrophy as a
It seems likely that as we get older and learning
becomes harder, that we neglect intensive learning which leads the
systems in the brain that modulate, regulate and control plasticity to
Learning, especially the learning of physical
skills or learning by doing, has been shown to protect people from
mental ravages of old age and provide some some resistance to the
symptoms, if not the brain shrinkage, of dementia.
Learning should therefore be a life long activity.
Exercise. [This is a Medina
rule. Our brains are optimized
for learning when we have just moved, when we are moving and when we
are preparing to move.] John Medina says: Exercise boosts brain power.
brains are built for walking - 12 miles a day.
improve you thinking skills move. [Imagine treadmills in the classroom
where students exercise in as preparation for absorbing information or
who walk on the treadmill at 1 to 2 miles per hour while taking their
gets blood to your brain, bringing it glucose for energy and oxygen to
soak up the toxic electrons that are left over. It also stimulates the
protein that keeps neurons connecting.
exercise just twice a week halves your risk of general dementia. It
cuts your risk of Alzheimer's by 60 percent.
we were trying to design a system that prevented learning, or made it
as difficult as possible we could hardly have done better than to
create schools where children are prevented from moving for hours and
hours per day.]
Survival. [This is a Medina rule. The
brain is not perfect it's a kludge. We evolved out of creatures that
not need sophisticated brains and our brains are still similar to
theirs in many ways. Most of the sophistication of the brain is
additional and compensatory.] John Medina says:
don't have one brain in our heads; we have three. We started with a
"lizard brain" to keep us breathing, then added a brain like a cat's,
and then toped those with a thin layer of jell-o known as the cortex -
the third and powerful, "human" brain.
took over the earth by adapting to change itself, after we were forced
from the trees to the Savannah when climate swings disrupted our food
from four legs to two to walk on the Savannah freed up energy to
develop a complex brain.
reasoning is a uniquely human talent. It may have arisen from our need
to understand one another's intentions and motivations, allowing us to
coordinate within a group.
Wiring. [This is a Medina rule. Each
brain is unique. It's content, structure and connection are all
unique.] John Medina says: Every brain is wired differently.
you do and learn in life physically changes what your brain looks like
- it literally rewires it.
various regions of the brain develop at different rates in different
two people's brains store the same information in the same way in the
have a great number of ways of being intelligent, many of which don't
show up on IQ tests.
children to learn easily their brain's need information structured
specifically for each one of their individual needs. Both the stating
point, the content interest and challenge, and the method of
presentation, should ideally be designed with a specific student in
Attention. [This is a Medina rule.
Quite a lot of work has been done in social psychology and neuroscience
on the subject of attention. These sciences have established that very
little in the way of information gets through to our brains if we do
not pay attention to it.] John Medina Says: People don't pay attention
to boring things.
brain's attention "spotlight" can focus on only one thing at a time: no
multitasking. (Perhaps we should mention that the more people try to
multitask the better they will get at switching from one task to
are better at seeing patterns and abstracting the meaning of events
than we are at recording detail. [To access details you normally have
to, in fact, reconstruct it from the pattern.]
arousal helps the brain learn. (Emotions can pin down details in
check out after 10 minutes, but you can keep grabbing them back by
telling narratives or creating events rich in emotion.
Short-term-memory. [This is a Medina
rule. Short term memory requires elaboration to keep it connected and
repetition to keep it active.] John Medina says: Repeat to remember.
brain has many types of memory systems. One type follows four stages of
processing: encoding, storing, retrieving, and forgetting.
coming into your brain is immediately split into fragments that are
sent to different regions of the cortex for storage.
of the events that predict whether something is learned will also 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.
can improve your chances of remembering something if you reproduce the
environment in which you first put it into your brain.
Long-term-memory. [This is a Medina
rule. Long term memory requires the information should be elaborated as
extensively as possible. Medina says repetition helps us store long
term memories. But repetition never truly occurs exactly the same way
each time we go over information. It is most probably the elaboration
that occurs while we are going over information, that fixes it in out
memories, rather than the repetition itself.] John Medina says:
memories disappear within minutes, but those that survive the fragile
period strengthen with time.
can improve your chances of remembering something if you reproduce the
environment in which you first put it into your brain.
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.
brains give us only an approximate view of reality, because they mix
new knowledge with past memories and store them together as one.
way to make long-term memory more reliable is to incorporate new
information gradually and repeat it [with additional elaboration] in
Sleep. [This is a Medina rule. The
brain does not need rest but it does need sleep.] John Medina says:
Sleep well think well.
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
neurons of your brain show vigorous rhythmical activity when you're
asleep - perhaps replaying what you learned during the day. [More
likely our brains are elaborating what we learned during the day by
connecting it to random memories already stored in our brains.]
vary in how much sleep they need and when they prefer to get it, but
the biological drive for an afternoon nap is universal.
of sleep hurts attention, executive function, working memory, mood,
quantitative skills, logical reasoning, and even motor dexterity.
Stress. [This is a Medina rule. Stress
is a response to threat. While helpful to learning if it occurs very
occasionally is actually damaging to learning if it is maintained for
long periods of time or every time something is learned.] John Medina
says: Stressed brains don't learn the same way.
body's defense system - the release of adrenaline and cortisol - is
built for an immediate response to to a serious but passing danger,
as a saber-toothed tiger. Chronic stress, such as hostility at home,
dangerously deregulates a system built only to deal with short-term
responses. [Constant threat of punishment at school is obviously very
stressful as is exclusion from peer groups.]
chronic stress, adrenaline creates scars in your blood vessels that
cause heart attack or stroke, and cortisol damages the cells of the
hippocampus, crippling your ability to learn and remember.
the worst kind of stress is the feeling that you have no control over
the problem - you are helpless. [In school students are are made to
feel helpless in many ways such as being bullied, or made to feel they
are too stupid to succeed.]
stress has huge impacts across society, on children's ability to learn
in school and on employees' productivity at work.
Sensory Integration. [This is a Medina
rule. If we wish to learn more effectively we should,] John Medina
says: Stimulate more of the senses at the same time.
absorb information about an event through our senses, translate it into
electrical signals (some for sight, others from sound etc.), disperse
those signals to separate parts of the brain, then reconstruct what
happened, eventually perceiving the even as a whole.
brain seems to rely partly on past experience in deciding how to
combine these signals, so two people can perceive the same event very
senses evolved to work together - vision influencing hearing , for
example - which means that we learn best if we simulate several senses
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.
Vision. [This is a Medina rule. They
say 'seeing is believing' and even though that is not always true] John
Medina says: Vision trumps all other senses.
is by far our most dominant sense, taking up half of our brain's
we see is is only what our brain tells tells us we see, and it's not
100 percent accurate.
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 areas registering motion others registering color,
etc. Finally we combine that information back together so we can see.
learn and remember best through pictures, not through written or spoken
words. [Unfortunately most teaching is composed of presenting
information through lecturing, writing on a board, or through reading
Gender. [This is a Medina rule.] John
Medina says: Male and female brains are different but the question is
why. What appears to be significant statistical differences between
male and female brains may not be inevitably determined, but rather may
be well within our ability to control.
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.
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.
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 those differences have
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.
Exploration. [This is a Medina rule.
Wanting to know why, how, where, when, and who is the news and also the
way we question, investigate and explore knowledge.] John Medina says:
We are powerful and natural explorers.
are the model of how we learn - not by passive reaction to the
environment but by active testing through observation, hypothesis,
experiment and conclusion.
parts of the brain allow this scientific approach. the right prefrontal
cortex looks for errors in our hypothesis ("The saber-toothed tiger is
not harmless"), and an adjoining region tells us to change behavior
can recognize and imitate behavior because of "mirror neurons"
scattered across the brain.
parts of our adult brains stay as malleable as a baby's, so we can
create neurons and learn new things throughout our lives.
Hard wiring. Hard wiring is not one of
Medina's rules. While we are developing inside our mothers bodies,
wiring is being laid down in our brains. This is done partly in
response to our genetic predispositions and partly due to environmental
conditions. This process continues after birth and throughout our
childhoods. The earlier this wiring is laid down the more difficult it
is to change later.
and compulsions are collections of actions and those elements
associated with those actions. With a habit associated actions and
elements can be overcome, altered or improved, but with compulsions the
associated actions and elements are hard to overcome and seem almost
obsessions and compulsions, the more you do it, the more you want to do
it; the less you do it, the less you want to do it. It is not what you
feel while applying the technique that counts, it is what you do.
that fire together wire together. The more you do something the more
that action tends to become automatic and all the actions and elements
associated with it also tend to become part of that automatic response.
that fire apart wire apart. The less you do something the less that
action tends to be automatic and all the actions and elements
associated with that action also tend to become less automatic.
neurons seem to lay down first attempts at creating motor plans for
observed actions so those actions can be imitated. These are not
perfect representations, but rather have to be developed to a more
perfect form through trial and error. However, once formed they can be
simulated in the mind ready to put into action.
neurons also fire in response to observing objects, especially ones
that could be involved in an action. It is likely, that objects gain
part of their meaning from the motor plan created by these mirror
words and other symbols used in communication readily invoke the
activation of mirror neurons. Symbolic representation of an action in
the form of a motor plan is probably part of the meaning of any symbol
such as an image or a word.
neurons also appear to be how the brain is able to predict the
intentions of others. Reaching for a certain object by one person, by
virtue of the activation of mirror neurons, begins the process in
another person of simulating motor plans. This process gains accuracy
by mirror neurons being sensitive to the context in which the actions
mirror neurons were activated though observation of another person's
face etc. it was found that this also activated the emotional firing
pattern of neurons in the limbic system allowing the person to feel
what the other person is feeling. This is also part of how we can
predict the intentions of others.
Although neuron growth is strongest during our youth up to about 17 or
18 years of age, the brain nevertheless continues to grow throughout
has been shown that neurons continue to appear throughout our lives and
that this occurs in response to learning. Learning new things is how
the brain grows.
brains can recover from massive damage but his requires that a
different part of the brain is cooped to perform the task that was
performed by the area of the brain that was destroyed.
functions like the executive functions in the prefrontal lobes and the
memory functions in the hippocampus seem to be too specific to be
duplicated in other parts of the brain. But brain functions relating to
language and the movement of limbs seem have alternate possibilities,
although everything has to be relearned, and is not relearned easily.
have four different ways in which they can compensate for damage. These
are map expansion, sensory reassignment, compensatory masquerade, and
mirror region takeover.
expansion. The boundaries of brain map
areas for various functions are constantly changing. The more we use
some function the more it grows and encroaches on nearby areas. More
control over a single brain area means the nearby area that is
encroached upon loses some control.
reassignment. This is where, if one sense
is blocked, as in the blind, the area assigned to that perception, (in
this case the visual cortex) is commandeered by the other senses such
masquerade. This is like the brain's redundancy system. There is often
more than one way for a brain to approach a task. Some people use
visual landmarks to get from place to place, while others have a good
sense of direction. If one of these brain areas is lost to injury the
brain can resort to the other.
Mirror region takeover. If part of one hemisphere
fails, the mirror region in the opposite hemisphere adapts, taking over
its mental functions as best it can. This is also a kind of redundancy
system. This can of course cause problems in whatever that part of the
brain was previously being used for.
Life long flexibility, learning, the
brain and a better world. So what does all this new knowledge
about the brain tell us? It tells us that a lot of people's guesses
about human nature and learning were correct. Freud was right when he
guessed that what happens to us in childhood is important. Montessori
was right when she guessed the environment of the child was the key to
effective development. The optimists were right when they guessed that
we can overcome disabilities by hard work and belief. It shows that the
people who think we are prisoners or hostages of fate or of our genes
were wrong. Our brains are ours to command and shape. It tells us that
we are masters of our own destinies. It tells us that we can become
stronger, more intelligent and that we can overcome our own
disabilities, but only if we are willing make a great effort. We should
not be surprised that this does not come easily. It also tells us not
to be lazy. The first rule of life is that 'what you don't use you will
lose' and it follows that what you use well will improve. Life is meant
to be lived and our miraculous brains are meant to be used.
may be fortuitous that we are now living in a world, that through 'the
world wide web', provides more challenge for mental activity than ever
before. While we are still living in a world where there are still many
temptations of the 'read only' world of one way (passive)
entertainment, we are learning there is now hope.
The internet has ushered in a new form of 'read
and write', two way (interactive) entertainment and learning. Clearly
our brains are better fitted for this form of entertainment and
learning. This will make us more intelligent, intelligent longer,
healthier, happier, better and more fulfilled people. We should be
warned, however, that the human brain thrives best on a lot of oxygen,
which it can only obtain through the exercise of our bodies, and this
should not be neglected while we sit in front of our monitors.