The
Treatment: Mediation & Brain Plasticity
Brain plasticity = ability of the brain to "rewire" itself.
This capability occurs predominately in the frontal lobes,
the area of the brain right behind the forehead and above
the eyes. Although they make up 40% of the volume, the
frontal lobes were the last part of the human brain to
evolve. They don't become fully operable until the late
teens or early twenties. They provide our sense of self-awareness,
our will power, and our humanity. They enable us to plan,
prioritize, and conceive the future. Damage to the frontal
lobes can deprive us of choice, intention, and conscience.
Professor Michael Merzenich of San Francisco , the world's
leading researcher in brain plasticity, discovered that
animals' brains that are passively stimulated aren't significantly
changed by experience. The "rewiring" occurs only when
attention is given to the stimulation. In other words,
to make a change we have to be actively attentive.
The "attention circuits" of the human brain are located
primarily in the frontal lobes. Here the initial stages
of learning take place. With attentive and adequate rehearsal,
the process then shifts to other parts of the brain, freeing
the frontal lobe circuits for the further acquisition of
new skills.
The frontal lobes also play an important role in selecting
what sensory input to attend
to—emphasizing certain stimuli while ignoring others.
The ability of "tuning in" and/or "tuning out" structures
our perceptions of external and internal events. Damage
to the frontal lobes can affect our ability to evaluate,
prioritize, and differentiate relevant from irrelevant
information.
One cost of "paying attention" is that activities in other
areas of the brain are significantly reduced. When we listen
intently, we become blind and numb to the world around
us. When we focus on minute details, we lose sight of the
big picture. We may get so lost in a book or a movie that
we lose all sense of time and place. This effect is called
"Hebbian learning," after psychologist Donald Hebb. The
changes that take place in brain cells and synapses as
a result of Hebbian learning is called "long-term potentiation"
(LTP).
On a neural level, neighboring cells begin "firing" simultaneously,
kind of empathically, even if only one of them receives
the initial electro-chemical stimulation. In Mind
Sculpture: Unlocking Your Brain's Untapped Potential ,
brain rehabilitation researcher Ian Robertson described
this phenomenon as "Cells that fire together, wire together."
On a metaphoric level, a coalition of actively firing cells
will commandeer their more passive neighbors, enlarging
the web of influence a specific stimulus can produce. On
a conscious level, we experience a “zeroing in” on particular
objects or events. For example: mothers can easily identify
the sound of their children's voices even in a crowded
and noisy playroom. And we all respond attentively when
we hear our names mentioned.
Research with musicians who play string instruments demonstrated
that while a larger than average part of their brains were
devoted to the fingers of their left hands, it resulted
in a less than average sensitivity in their left palms.
Likewise, the folk adage that a loss of one sense, such
as sight, leads to the enhancement of other senses has
been scientifically justified by evidence that visual areas
of a blind person's brain are taken over by touch when
he learns Braille.
The commandeering of brain cells which results in the
acquisition of new skills can be disrupted if we are not
allowed to dream. Although REM (rapid eye movement) sleep
takes up just 20% of the night, research indicates that
without such dream time learning and memory suffer. This
is why cramming all night for a final may get us through
the test but does nothing to enhance our understanding
of the subject matter.
The same does not hold true if non-REM sleep is disrupted.
We may be tired and cranky, but our memories will still
function. Hence, it is not enough to "sleep on it," we
have to "dream on it" to make significant changes within
our brains.
Neural networks that are derived from experience or practice
will break down from disuse, or as Robertson said "Cells
that fire apart, wire apart." This is why we may remember
only snatches of old, familiar songs or experience a sense
of "being rusty" at things we used to do so well. Brain
cells don't whither away when unused. They are simply commandeered
for other purposes. In weightless space, astronauts lose
their kinesthetic sense of direction. Without gravity,
they have no "this side up" cue. They have to depend entirely
on their eyes to orient themselves as they float freely
in the space shuttle. After an extended time in a space
lab, they even lose the sense of their limbs. They have
to look to see where their arms and legs are. This is why
astronauts "walk funny" when they finally return to Earth.
On average, it takes four to eight days for their brains
to "rewire" under the influence of gravity.
This extraordinary, and until recently, unrecognized capacity
our brains have for continually restructuring themselves
holds great promise for people with traumatic brain injuries
(TBI). In some cases, neural networks that have been 90%
damaged have reorganized into functioning systems again.
They do so by "working around" the dead cells and joining
together with surviving neighbors.
As might be expected, higher and broader education provides
a significant advantage when it comes to overcoming brain
injuries. The more connections there are and the stronger
those connections are, the more likely a patient will recover
functional capacity, provided that the therapy is progressively
organized. Sporadic or poorly organized treatment is like
knitting and then unraveling a sweater. It may keep us
busy, but in the end nothing has been achieved.
The most effective form of teaching, and subsequent brain
restructuring, is mediation. The mediator is a kind of
external frontal lobe, selecting and highlighting what
is significant, downplaying or concealing what is distracting.
Designs for Strong Minds™ and Learning
How To Learn exercises
are designed to do just that and more. They are organized
progressively and around different logical structures.
Think of them as a full brain workout, cross-training and
restructuring the brain to maximize potential naturally.
© Copyright 2004 Donalee Markus, Ph.D. & Associates |