Teaching With the Brain in Mind

ellar cortex. From exercise (repeated motor learning),
the brain develops greater density of blood
vessels in the molecular layer (Black et al. 1990).
Some researchers found that an area of the midbrain
involved in attentional processing—the superior
colliculus—grew 5 to 6 percent more in an
enriched environment (Fuchs, Montemayor, and
Greenough 1990). Using fMRI (Functional Magnetic
Resonance Imaging) technology, researchers
at the University of Pennsylvania discovered that
our brain has areas that are only stimulated by letters,
not words or symbols (Lasley 1997). This
suggests that new experiences (like reading) can
get wired into the malleable brain. In other words,
as you vary the type of environment, the brain
varies the way it develops.
Yet all of this can get tricky. A student’s early
sensory deprivation can play a role. “If there is a
bad experience, the wrong synapses are shed and
the system malfunctions,” says University of Illinois
neuroscientist William Greenough (1997). Retaining
excess synapses can be harmful, as in the case
of Fragile X mental retardation. At school, there’s
more interest than ever in creating the right kind of
enriching environments. That’s for good reason.
One of the most convincing arguments comes from
the former director of the Institute of Mental
Health, Frederick Goodwin. He says, “[T]here is
now increasing understanding that the environment
can affect you. . . [;] you can’t make a 70 IQ person
into a 150 IQ person, but you can change their IQ
measure in different ways, perhaps as much as 20
points up or down, based on the environment”
(Kotulak 1996). That’s a 40-point range! Just how
much can a school affect the brain? Neuroscientist
Bob Jacobs confirms that animal research on brain
enrichment translates directly to human brains. He
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Enriched Environments and the Brain
found that in autopsy studies on graduate students,
they had up to 40 percent more connections than
the brains of high school dropouts. The group of
graduate students who were involved in challenging
activities showed over 25 percent more overall
“brain growth” than the control group. Yet education
alone was not enough. Frequent new learning
experiences and challenges were critical to brain
growth. The brains of graduate students who were
“coasting” through school had fewer connections
than those who challenged themselves daily
(Jacobs, Schall, and Scheibel 1993). Challenging
sensory stimulation has been rightfully compared to
a brain “nutrient.” Figure 4.1 illustrates the differences
between impoverished and enriched neurons.
FIGURE 4.1
How Enrichment Changes the Structure of
Brain Cells
Impoverished
Neuron
Enriched
Neuron