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At first glance, it appears nothing is wrong with
Gail, an energetic sixth-grader who enjoys painting, sings in the church choir,
and is a midfielder on her school's soccer team. She is well-liked by her
classmates and spends time in their homes for sleepovers and other events.
However, upon closer examination you will observe that her right arm dangles,
about fifty percent dysfunctional since birth due to what is called congenital
hemiplegia, or cerebral palsy, a condition brought on by bleeding in the brain
during infancy. In Gail's case, it affected the right arm since the injury
occurred in the left hemisphere, significantly limiting hand grasping and gross
movement of the limb. It can affect legs, trunk, face, or other regions of the
body depending on the degree and location of the cranial bleeding. In her case
the anomaly is not noticeable until you observe her walk or run because the arm
dangles rather than move to the rhythm and direction of a normal arm, and all
fine motor manipulation is done with the left hand.
However, her parents were
informed of a treatment that aggressively attends to disabled limbs, in several
cases improving functionality. It seemed too good to be true, perhaps another
false hope, but they would not leave any stone unturned. With as much optimism
as they could muster, they enrolled Gail in a program called Constraint Induced
Movement Therapy (CIMT)1
thirty minutes from their home. What made it unique was the intensity level of
three-hour regimens, five days a week, of hand, wrist, shoulder dexterity,
strength, and range of movement exercises, a dramatic departure from some of
the procedures used by a local physical therapist in previous years. The
training included an assortment of apparatus such as dumbbells and large rubber
rolling balls, along with routines that entailed food utensils, writing, and
painting. Her left (normal) arm was put in a sling and mitt during the sessions
to maximize focus on her right arm.
In time, Gail became
increasingly more engaged through the strenuous ordeal. In fact, in one month
she made measurable improvements in the mobility of her right arm and hand,
empowering her to have significant control over that limb including tasks such
as combing her hair, putting on clothes, buttoning her blouse, using a fork,
and several other manipulations we perform regularly. The grueling regimen
created an amazing transformation that delighted Gail and her parents,
inspiring her to take on tasks she thought unimaginable. "We found it hard
to believe that this therapy could make such a major difference in her life.
She brims with confidence and hopes to take up the piano or guitar soon."
Neuroplasticity
Constraint Induced Movement Therapy was developed by
Edward Taub, behavioral
neuroscientist at the University of Alabama-Birmingham. He put stroke victims
under a regimen that immobilized their functional arm in a sling for two weeks
while undergoing physical therapy six hours a day for consecutive five-day
weeks focusing on their partially-paralyzed arm. At the end of this movement
and touch emphasis, the stroke individuals, like Gail, performed tasks (dress,
eat, and pick up objects) with greater proficiency than stroke patients that
did not get the therapy.
Why does Constraint
Induced Movement Therapy create such a dramatic
transformation in people like Gail and so many hemiplegia and stroke victims?
The brain undergoes an extensive rewiring called neuroplasticity when the motion and
tactile exercises are intense and lengthy, restructuring the neural network
with new cell development and branching. Functional Magnetic Resonance Imaging,
(fMRI), reveals that it occurs in the brain's motor region for
both the weak as well as the functional arm. Moreover, Taub concluded that the
brain reprograms healthy neurons in adjacent or distant
areas to accommodate new roles, substituting for the damaged neurons when
targeted areas of the body are stimulated.1
It was the first time an
experiment revealed that brain rewiring can occur after a stroke. The program
is intensive but significantly improves functionality of limbs and other
regions of the body, and therapists around the world are trained to perform
Constraint Induced Movement Therapy. Many people have benefitted from this
regimen proving that there is enormous flexibility and regenerative capacity in
our brain – beyond what medicine thought possible. What was considered
unimaginable is now reality as people all over the world can gain some measure
of control over regions of their body previously rendered useless.
Gross brain
changes during sensory deprivation
Gail's story is
inspirational. The Constraint Induced Movement Therapy program has helped
many people recover functionality in their limbs through intensive and focused
exercise and there is now evidence that neuroplasticity occurs in regions of
the brain other than motor control sectors. Imagine, for instance, volunteering
to be blindfolded five days. I would not do it, yet several signed on and found
themselves hobbling around a hospital wing with nothing to do but learn braille
and hear tones. The experimenter, Alvaro Pascual-Leone, Professor of Neurology at Harvard Medical School, and his
team evaluated the participants by scanning their brains using Functional
Magnetic Resonance Imaging, (fMRI). With their vision in shut-down mode, they had to rely on
the other senses particularly touch, interpreting the bumps of the braille
marks, and hearing, by distinguishing notes.1,2 The participants'
brains were scanned using fMRI.
Though the volunteers
used the visual cortex throughout their
lives, that region now faced the daunting task of adjusting to five full days
with no stimulation and did it in an unusual way. The fMRI revealed that the visual cortex was not dormant at all but activated when it heard the tones or felt the braille symbols. In fact, the somatosensory cortex, the region that normally processes tactile stimuli
diminished and the visual cortex took on that role. The visual cortex underwent a neuroplasticity that sprouted
connections enabling it to sense sound and touch!
Though regions of the
brain differentiate in the womb to serve specific sensory roles after birth,
there is flexibility in the cellular information that adapts to anything the
world throws at us.
In just five days the
visual cortex of these adults
participated in neuroplastic functionality, changing at the neuronal level by
creating new interconnections, or what is called dendritic sprouting. It has been a hot topic since the 1990s and fMRI has opened the door to
investigate the many ways the brain adapts to variations in environmental
stimuli.
Even before this remarkable experiment, neurologists were aware that people deaf from birth detect movement faster and more accurately than those that hear. In addition, blind people revealed a dynamic flexibility: they learn braille to process tactile sensation from their fingers, detect sounds better than sighted individuals, and perform linguistic thinking such as producing verbs when hearing nouns. It took Pascual-Leone's scans to show that the area meant to see, can do more.
Can
thought lead to neuroplasticity?
These experiments
revealed a) that the brain is structured to have "some rudimentary
somatosensory and auditory connections to the visual cortex"3 allowing the nervous system to
reorganize based on functional need, and that b) the brain is enormously
malleable.
More simply, sheer will
and repetition results in profound changes in the brain because we have
regenerative powers at the nervous system level, much like a salamander regenerates a
limb after it is lost or damaged. Taub and Pascual-Leone have revealed to the
world that brains can be reconfigured upon demand.
Schools as neuroplasticity centers?
1. The brain is continuously interpreting the
world
A spider landing on our
arm requires an instantaneous brush from the other arm, but the sight of a
friend walking toward us elicits another reaction. There is a set of behaviors
based on context to spark an interaction depending on whether we are at work or
a social event because our behaviors range from impulsive to deliberate – we
judge what is in our best interest. We make decisions all the time, some that
we regret, but the accumulation of all of them shape our personality.
Delivering a stupid statement that creates strife might make us pause at the
next encounter.
Nerve
cells, or neurons, make up brain
tissue, encompassing several functional regions. The differentiation is
in the genetic programming that dictates the biochemical
activity in each region. Each cell has the potential to produce an electrical
impulse when prompted and communicate with the next cell at a junction known as
a synapse, a small gap where
neurotransmitters burst
from one neuron and touch receptors on the next, setting off the impulse that
travels down the length of that cell and releasing neurotransmitters to the
next neuron.
Furthermore, the nervous
system is poised to react
instantaneously, activating electrochemical processes between near and far
reaches of the brain as well as extremities of our bodies. Nerve cells do this
by electrical conductivity. Each cell communicates at the synapse, where
chemicals called neurotransmitters burst out of the first cell, move across
the liquid barrier to the next, touch receptors, and initiate the electrical
impulse, which release another army of neurotransmitters to the next cell.
Depending on the tissue the speed of that impulse ranges from 1 to 120
meters/second. The impulse continues to a targeted region to accomplish any
number of effects: cause muscle contraction such as emulsifying food in the
digestive system or making our legs walk. The impulse's target might be another
region of the brain to activate the production of hormones that are then sent
to specialized organs via the circulatory system to stimulate activity in
another part of the body.
Scientists identified a
protein that is involved in the construction of nerve tissue and the
connections to other nerve cells. It is called brain-derived neurotrophic factor, BDNF, and is intricately linked to the transformation and growth
of the neural network called neuroplasticity. It works in conjunction with a host of other biochemicals
but has been identified in many experiments to be the component that correlates
with improved cognition. It played a significant role in the neuroplasticity demonstrated in the
Taub and Pascual-Leone experiments.
It targets neurons in several places,
including the hippocampus, a location associated with the learning, memory, behavior,
and emotion circuits. Our executive functions reach maturity at
around age twenty-five, but the BDNF then declines and our
hippocampus and associated regions reduce in volume about one percent per year.
2. Oxygenation stimulates neuroplasticity in the
memory region
To show that this
reduction can be reversed, Art Kramer, Director of the Beckman Institute for Advanced Science
& Technology at the University of Illinois, put one hundred twenty
sedentary adults 55-80 years old on a walking program, forty minutes, three
days per week, for one year. The findings are amazing: they saw a(n) a) two
percent increase in their dentate
gyrus of the hippocampus using fMRI, b) improvement in spatial memory, and c) higher serum
BDNF concentration. The
team concluded that aerobic training prevented hippocampal volume decrease and improved
memory function by building on the existing neurons. The control group that
did a regimen of balance and strength exercises experienced a one percent decrease in the volume of the
hippocampus during that year.4
The consensus
among scientists is that the human brain is plastic throughout life. That means
you can learn new tasks. While the brain has the greatest plasticity in youth to learn to
play a musical instrument, master a foreign language, play a new card game,
memorize lines from a play, or recover limb functionality after a stroke,
adults can perform these as well by keeping a rigorous practice schedule by
activating regions in the brain that are relevant to that mode of thinking. It
requires discipline but that is what it takes to make gains in neuroplasticity.
3. Positive and negative emotional components side
by side
Richard
Davidson, Vilas
Professor of Psychology and Psychiatry at the University of Wisconsin-Madison, showed that the left prefrontal cortex is connected to circuitry linked with positive
emotion and the right prefrontal cortex negative. Using fMRI, subjects viewing images
covering a range of emotional content reveal distinct left or right prefrontal
cortex activation. He first distinguished
predominantly left-sided prefrontal cortex activated individuals from predominant-right-sided
people. He then had both groups select from a list of positive and negative
adjectives describing how they felt most of the time. The words 'strong',
'enthusiastic', 'alert', 'proud', and 'excited' were selected more often by the
predominant-left-sided participants and the words 'distressed', 'scared', and
'nervous' were selected more by the right-sided group. His team also found
corresponding physiological parameters such as levels of the stress hormone
cortisol and other biological
and immune-related biochemicals in these groups.5
Having both attributes,
negative and positive, might be advantageous in that a child may need to
experience negative cues and corrective measures to make good judgments later
in life. Nevertheless, Davidson's findings are significant in that the circuitry for
negative personality and depression is identified and found to be susceptible
to modification medicinally and through cognitive therapy.
However, in the education
context, understanding how to activate left-side prefrontal cortex circuitry has a lot to
do with the attitudinal elements of assertiveness and drive to succeed
in the classroom. It is in this
realm that instructors can create an environment in their classrooms that
stimulate content assimilation and love of learning, a place where students feel valued for
their effort, intelligence, and advocacy.
The Brain in School
Can teachers take
advantage of the plasticity to improve mastery of
facts and skills? The answer is a resounding yes and recent cognitive studies
show that the brain responds to a host of instructional practices including
interactive face-to-face experiences and
movements that amplify attention and assimilation. Just as Gail saw dramatic
improvement in her right arm and hand flexibility through repetitive motions of
that limb, the brain can respond in an analogous fashion to manipulate
knowledge for storage and interpretation.
This book is interested
in the cognitive potential of the brain in an engaging academic and psychomotor
environment as well as the motivational elements closely coupled to learning.
We are endowed with an overabundance of neurons that undergo cross linking before birth and throughout our existence. The brain is a learning
machine throughout life but there are specific windows of opportunity in
childhood and adolescence that are particularly critical for a range of
cognitive and emotional functionalities. The potential for brain activation,
that is, the capacity to learn new information or skills is continuous, but we
as educators must maximize knowledge assimilation and generate the motivation to
learn when the windows of opportunity are greatest.
We might consider dopamine, a neurotransmitter that affects the
functioning of blood vessels, kidneys, pancreas, immune system, and digestion.
For our discussion, however, it is produced by the arcuate nucleus cells in the
midbrain's hypothalamus, then
migrates and attaches to the nucleus
accumbens in the hypothalamus. Dopamine is secreted in association with a) perception of
consequences followed by b) the attentiveness while performing tasks based on
getting a reward or preventing a punishment. In other words, dopamine secretion varies
throughout the day as our brains analyze the cost/benefit ratio of everything
we do.
The relevance in the
classroom is that it increases when students perceive our presentations as
pertinent to their needs and interests. For example, the sustained action of
dopamine helps a student finish
a math assignment whether driven by the delight to do math problems or the
realization that failure to finish will result in a low grade. If you must
perform a task, dopamine keeps you attentive to
completion. If you enjoy doing math problems, the perceived reward is the pleasure you receive in the
process, particularly finding out that you got the correct answer to every
problem. The reward is getting it done so that you can move on to other
concerns, and even acquire the knowledge needed to perform well on the next
day's quiz. Consider other reasons such as appearing competent in front of
peers as well as parental expectations.
Dopamine levels
vacillate. If a student experiences stress in school or is bored, the amygdala is going to be on
alert and dopamine will increase at the
end of class or when it is time to go home. However, as the student copes with
anxiety or monotony throughout the school day,
motivation to
learn decreases and the signals associated with processing memory of subject
matter in the hippocampus and the prefrontal
cortex will be limited and the dopamine level will drop.
In school
Furthermore, the brain is
activated at several levels when students serve as classroom facilitators as well as in small
group, face-to-face encounters. For one,
the proximity and eye contact registers in the brain
as acceptance by peers, and that motivates individuals to cooperate. Secondly,
psychomotor activities such laboratories, crafts, art, drama, and exercise
involving tactile and cardiovascular emphasis raise serum BDNF levels amplifying
concentration and cognition.
Schools that include well-structured team-based assignments and student-led discussions, coupled with gross movement, hand-eye, and cardiovascular activities significantly maximize cognitive functionality in children.6
What activates the minds
of students to produce the greatest level of knowledge acquisition? What can
educators do to create the most productive atmosphere where students enjoy
learning content areas? How can you feel a
sense of accomplishment and delight as your students carry the ball and develop
elevated levels of competency?
The human brain is
continuously on alert as it performs various functions: receive sensory data,
reason, and experience emotions. A student's perspective in this regard is
different at school compared to their home or attending a rock concert. With
the advent of iPhones and the many Net
outlets, young people are very focused, yet not interactive at a face-to-face level, seeing the
world from a different perspective from ours a generation ago. Moreover,
attention is different when a child is planted at a desk compared to all the
interesting online venues with friends, videos, and shopping. Because humans
use more of their brain during social encounters, students performing tasks in
teams result in heightened engagement, ostensibly due to the peer validation
generated during the banter. Moreover, they feel valued as contributors to a
cause, and the dopamine increases since the
task is perceived as rewarding and even pleasurable. Simply sitting in close
proximity with peers is validating, particularly for loners.
Interactive lessons promote
neuroplasticity, builds new connections within the fabric of our gray
matter, and maximizes camaraderie and assimilation of
content areas.
Stimulating the positive in class
It boils down to this:
create a motivating atmosphere, and students will comply with your lesson
objectives, complete tasks, and derive an appreciation for the subject, its
historical context and you, the facilitator. As I mentioned earlier, humans are
social creatures and use both spoken and written means to express language.
Socializing stimulates the brain to formulate words and the grammar associated
with language. A talented instructor could be an effective lecturer and
transmit content in an organized fashion and even raise issues that make
students think deeply about a subject.
However, the lesson is more inclusive when students have roles, are assertive and validated, exchange ideas in a collaborative setting or facilitate class discussions. There is enjoyment, too, as observed by the exchanges and look on their faces!
The diversity of such a
program is brain activating and will promote attentiveness throughout the school
year because students enjoy the feedback from their members as
well as the close-order seating that maximizes eye contact and friendship. Acknowledgement
drives the dopamine circuitry and makes
the sessions pleasurable and rewarding. Furthermore,
it reduces the anxiety that can build up in
the uncertain social atmosphere of a school and furthers a student's perception
that they are a valued member of the community, calming the fear-sensitive
amygdala. It allows the
free-flow assimilation of information, which ends up being processed by the
memory centers, the hippocampus and prefrontal cortex, analogous to Davidson's experiments with facial expressions.
Constraint Induced
Movement Therapy directs
neuroplasticity to regions in the
brain that supplant damaged neurons with new and
functional cells to renew functionality in the targeted area of the body. In
the academic realm students validate one another in this
interactive manner from short
worksheets to full-scale projects sharing ideas and
delegating responsibilities.
I draw this conclusion: neuroplasticity is stimulated in a validating environment, and students gain a sense of empowerment, become alert and engaged, perceive ownership as they manipulate the knowledge flow.
We are sanctioned to
create lessons that generate decisiveness in students that foster love of
learning, excellence, goal setting, and kindness. It extends into college and
adulthood and is passed on to the next generation.
Economists Raj
Chetty and John Friedman of Harvard University and Jonah Rockoff of Columbia University found that quality
instruction can have a substantial impact on the lives of children. By
examining school district data of over one million students from fourth grade
to adulthood, it was determined that having an "above average"
teacher results in a student accruing additional lifetime earnings of more than
$52,000 or $1.4 million in gains for the whole class. Furthermore, they are
more likely to attend college, live in better neighborhoods, save more for
retirement, and are less likely to have children as teenagers.7
BOX 1.1
Functional Magnetic Resonance
Imaging (fMRI)
The MRI scanner is enclosed in an
electro-magnet fifty thousand time greater than the earth's field. When in
operation the field in the scanner affects the nuclei of atoms. Functional
MRI is used to measure brain activity and detects regions that are most
oxygenated, or highest blood flow. fMRI creates
activation maps to reveal heightened activity to clarify mental processes. It
is a non-invasive method and is safe for participants since it does not
entail radiation.
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References
1. Pascual-Leone, A., Hamilton, R., (2001). The Metamodal Organization of the Brain, Progress in Brain Research 134: 425-427
2. Kauffman, T., Théoret, H., Pascual-Leone, A.,
(16 April 2002). Braille character
discrimination in blindfolded human subjects.
Neuroreport: - Volume 13 - Issue 5
- 571-574
3. Pascual-Leone A., Amedi A., Fregni F., Merabet
L., (2005). The plastic human brain
cortex, Annual Review Neuroscience, 28:377-401
4. Colcombe, S., Kramer, A., Erickson, K., Scalf,
P., McAuley, E., (2004). Cardiovascular fitness, cortical plasticity, and aging. Proceedings of the National Academy of
Sciences USA. Mar 2; 101(9):3316-21.
5. Davidson, R., Understanding Positive and
Negative Emotion
Retrieved from:
http://www.loc.gov/loc/brain/emotion/Davidson.html
6. Johnson, D. & Johnson, R., (1989). Cooperation
and competition: Theory and research. Edina, MN: Interaction Book Company
7. Chetty, R., Friedman, J. Rockoff, J., (2011).
The long-term impacts of teachers: Teacher-value added and student outcomes in
adulthood, National Bureau of Economic Research
