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The Brain Ultimatum—Got Nerve?



Imagine designing a device to be used by human hands without considering the nature of the

hands. Imagine learning in a classroom where instruction takes place without taking into account

the brain and how it functions! Recent discoveries in neuroscience have grabbed the attention of

many educators worldwide. One challenge for educators is to learn about the brain‟s innate and

natural learning, thinking and remembering processes if they are to teach the way the brain

naturally functions. The more we understand the brain, the better we will be able to design

learning experiences that align with how it learns best.



The entire body is composed of cells—muscles, bones, intestines, skin and brain. The brain takes

up less than two percent total body weight yet it is responsible for twenty-percent of the body‟s

energy consumption. Each group of cells has a highly specialized job to perform. Two types of

cells make up the central nervous system—neurons and glial cells. Neurons are found in the brain

and spinal cord and number about 100 billion. Neurons are specialized to transmit information or

communicate with one another forming networks by means of electrical and chemical signals.

Glia cells in the brain are helper cells and they outnumber neurons 10 to 1. The roles of the glial

cells include: assisting in the development of the fetal brain; removing debris of dead cells

following damage to the brain, helping the neurons mature; laying down myelin a wrapping

around some axons which speeds the electrical impulse; and maintaining an appropriate chemical

environment in the brain.



Positron emission tomography (PET) scans allow researchers to picture the anatomical areas of

the brain that become active while a person performs various mental tasks. The subject is injected

with a small amount of radioactive glucose, which the blood carries to the brain. A series of

mental activities are performed and the areas of the brain responsible for these various processes

use much more radioactive glucose than other areas. When this happens, the radioactive material

emits antimatter particles called positrons, which collide with the brain‟s electrons and produce

gamma rays. Sensors outside the skull detect these rays. A computer uses this information from

the sensors to construct colored images (tomographs). The areas of the highest glucose use

(greatest activity) show up in white, red and yellow while areas of lesser use glow as green, blue

and purple. PET scans of a reader show that much more frontal lobe activity occurs when the

subject reads silently than when he or she is reading aloud to others. Activity in the frontal lobes

often indicates higher-level thinking. The scan of the student reading aloud glows brightly in the

motor area of the brain that governs speech, while showing little activity elsewhere. One way to

interpret these scans is that there is more comprehension of what is being read when one reads

silently.



Note figure 1-1 which is a picture of dendrites growing. It is a picture of learning. As we learn

specific neurons are growing specific new dendrites for that specific new object of learning. The

other neurons‟ axons connect with these dendrites, as well as with other neurons‟ cell bodies, at

connection points called synapses. Synapses are very small gaps between pre-synaptic neurons

and post-synaptic neurons. The growing and connecting dendrites are learning. In fact, as we feel

ourselves learning, instead of saying, “I feel I‟m getting it; I‟m learning it, “we could more

accurately say, “I feel my dendrites growing and my synapses connecting.”









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Figure 1-1 Growing Dendrites = Learning







Neuronal communication is not at all like mailing a letter. See figure 1-2. It is the biological

equivalent of a pinball machine. The presynaptic cell shoots a transmitter message across the

synapse, reloads and fires again. On the other side of the synaptic cleft, transmitter messages hit

or miss their targets‟ receptors, bounce off, and fall prey to waiting enzymes. The postsynaptic

cell sums up the receptors‟ hits, adds and subtracts incoming messages, and relays the conclusion

to the next cell. Researchers recognize that neurons are dedicated and articulate correspondents—

as eager to reply as they are to receive. In a language crafted from a rich vocabulary of

transmitters, clans of receptors, extended families of second messengers, teams of gene-switching

transcription factors, brain cells debate and maneuver, always tailoring their responses to match

the changing volume and timbre of the discussion. Far from silent, the postsynaptic cell does not

just passively soak up transmitted messages; it responds. Neurotransmitters damp down or fine-

tune events on the presynaptic as well as postsynaptic side of the synapse (see figure 1-3),

regulating such features as firing rate, transmitter synthesis, and receptor number. These feedback

mechanisms balance the relative intensity of intraneuronal communication to maintain a dynamic

equilibrium. Learning is also a dialogue—between past and present, experience and physiology.

Learning, and behavior in general, cause massive changes in the way neurotransmitters are made,

how they act on receptors and ultimately, which nervous system genes are expressed.









Figure 1-2 Neuronal networking









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Figure 1-3 Synapse



Innate resources of the Brain:

The brain has a natural learning process.

The brain has an innate sense of logic.

The brain is an innate pattern seeker.

The brain is an innate problem solver.

The brain is innately imaginative and creative-seeing in new ways.

The brain is innately motivated to learn.



Five Rules for How the Brain Learns

1. Dendrites, synapses, and neural networks grow only from what is already there. We learn

by connecting new learning to something we already know and then constructing new

levels of neural knowledge structures, level by level, twig by twig, from that prerequisite

foundation. To teach or learn something new, we start with something familiar as the

foundation from which to construct the next level of knowledge or skill.

2. Dendrites, synapses, and neural networks grow for what is actively, personally and

specifically experienced and practiced. As people actively practice an object of learning,

they get better at what they are practicing because their brains are growing more

dendrites, synapses and neural networks for that specific object of learning.

Unfortunately, in the same way, if an experience is negative or abusive and it is

repeated—practiced—often enough, that network will get stronger; and learners will

become better at (become more and more accustomed to) being abused.

3. Dendrites, synapses, and neural networks grow from stimulating experiences. Because

learning, thinking and remembering are active physiological, chemical, electrical

phenomena, stimulation is needed to arouse the brain to grow new neural structures and

fire synapses. For example, a stimulating experience would be processing with others, as

when getting and giving feedback about an object of learning. Stimulating experiences

also arouse the brain to use its innate resources that is its impulsion to seek patterns, solve

problems, and understand how the world works and how to make it work. These are

activities that cause neural structures to grow and connect. Unfortunately, even negative

and abusive experiences are stimulating because they impel us to see how that abusive

world works and how to act and survive in it.







3

4. Use it or lose it. If people stop doing something that they had previously learned, even if

it is enjoyable or useful, after a while they might, because of neural pruning, forget some

or all of it.

a. If a girl took three lessons on how to water ski at age 8, and then did not try to

water ski again until age 42, she might have to start from the beginning. Most

people, in this situation, would lose the small number of dendrites, synapses and

neural networks grown during these three lessons.

b. A boy rides his bike everyday from age 10 until he goes to college. While in

college he rides his bike from the dorm to class. Once he lands his first job, he

stops riding his bike for ten years. At age 34 he decides to ride his bike again.

This person may not have much trouble starting up with bike riding even after a

ten year hiatus. Although the brain prunes unused structures, when those

structures are vast and deeply embedded from years of constant use, pruning will

have less of an effect.

c. A young boy has been emotionally abused as a child and is always repeating

negative self-talk—what his alcoholic father told him—that his is stupid, a loser,

worthless. But as a young man, seeking help, joins his church youth group. In

this group, he comes to understand where his negative self-image and self-talk

came from and that, by understanding and using the „use it or lose it‟ rule, he can

lose the negative network by not repeating its negative words. He also starts

practicing positive self-talk in order to grow a new, positive neural network. The

more he practices the positive self-talk and ignores and rejects the negative talk,

the stronger the positive network will grow and the weaker the negative one will

become—perhaps atrophying altogether over time.

5. Emotions affect learning. Emotions produce chemicals that enter the brain and

physiologically affect the synapses and, consequently, the brain‟s ability to think, learn,

and remember. Emotions and thinking, learning, and remembering are inextricably bound

together.



Major Points about Learning

1. Your brain loves to learn, knows how to learn, and was born to learn!

2. You learn what you practice.

a. Practice is making mistakes, correcting mistakes and learning from them and

trying over and over and over again

b. Making and learning from mistakes is a natural and necessary part of learning

3. You learn what you practice because when you practice your brain is growing new

dendrites and connecting them at synapses.

4. Learning takes time—you need time to grow and connect dendrites.

5. Sleep, proper diet and exercise helps impacts brain function.

6. If you do not use it, you can lose it. Practice and use what you learn.

7. Your emotions affect your brain‟s ability to learn, think, and remember.

a. Self-doubt, fear, frustration, anger prevent your brain from learning, thinking and

remembering

b. Confidence, interest, novelty, stimulating experiences help your brain learn,

think, and remember

8. Remember, you are a natural-born learner.



Sources:

Rita Smilkstein, We‟re Born to Learn, Corwin Press 2003.

Eric Jensen, Teaching with the brain in mind, ASCD 1998

Patricia Wolfe, Brain Matters, ASCD 2001

Debra Niehoff, The Biology of Violence, The Free Press 1999







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