Teaching With the Brain in Mind

that cannot be accomplished individually—it
requires groups of neurons (Greenfield 1995).
How Do We Learn?
What the human brain does best is learn. Learning
changes the brain because it can rewire itself with
each new stimulation, experience, and behavior.
Scientists are unsure precisely how this happens,
but they have some ideas what happens.
First, some kind of stimulus to the brain starts
the process. It could be internal (a brainstorm!) or
it could be a new experience, like solving a jigsaw
puzzle. Then, the stimulus is sorted and processed
at several levels. Finally, there’s the formation of a
memory potential. That simply means the pieces
are in place so that the memory can be easily activated.
As educators, it’s well worth our time to
understand the basics of these. It may give us some
useful insights into how students learn.
The Stimulus
To our brain, we are either doing something we
already know how to do or we are doing something
new. If we are repeating an earlier learning,
there’s a good chance the neural pathways will
become more and more efficient. They do that
through myelination, which, as noted earlier, is the
process of adding a fatty coating to axons. Once
myelination has occurred, the brain gets more efficient.
Washington University School of Medicine
researchers Hanneke Van Mier and Steve Peterson
discovered that while many areas of the brain will
“light up” on a PET scan when a new task is initiated,
the brain “lights up” less and is used less the
better the task is learned. Novices use more of
their brain, but they are less efficient at how they
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The Learning Brain
use it. This quality illustrates how quickly our
brain adapts and rewires itself.
While exercise is doing what we already know
how to do, stimulation is doing something new.
Seeing a new movie, listening to new music,
singing a new song, visiting a new place, solving a
new problem, or making new friends can all stimulate
the brain. As long as it’s coherent, this novel
mental or motor stimulation produces greater beneficial
electrical energy than the old-hat stuff. This
input is converted to nervous impulses. They
travel to extraction and sorting stations like the
thalamus, located in the middle of the brain. In
intentional behavior, a multisensory convergence
takes place and the “map” is quickly formed in the
hippocampus (Freeman 1995). From there, signals
are distributed to specific areas of the brain.
Once this input is received, each brain cell acts
as a tiny electrical battery. It’s powered by the difference
in concentration of sodium and potassium
ions across a cell membrane. Changes in voltage
help power the transmitting of signals for dendritic
growth. Neurotransmitters are stored in the ends of
the cell’s axon, which nearly touches the dendrites
of another cell. Typically, they’ll either be excitatory
(like glutamate) or inhibitory (like GABA, or
gamma-aminobutyric acid). When the cell body
sends an electrical discharge outward to the axon,
it stimulates the release of those stored chemicals
into the synaptic gap, which is the space between
the end of an axon and tip of a dendrite, as represented
in Figure 2.7.
Once in that gap, the chemical reaction triggers
(or inhibits) new electrical energy in the receptors of
the contacted dendrite. It’s electrical to chemical and
back to electrical. There, the process is repeated to
the next cell. Eventually, the repeated electrical stimulation
fosters, along with an increased input of