The Phenomenon of Brain Neuroplasticity
The ability of neural networks to repair themselves became dramatically
evident in the 1990s. Stroke victims, for instance, who have lost access to parts
of their brains, may be able to regain all or part of their lost functionality. Their
neural networks rewire around the parts of the brain damaged in the stroke,
sometimes restoring full function.
The work of physician Eric Kandel, MD, showed that within one hour of repeat
stimulation, the number of synaptic connections in a neural bundle can double
(Kandel 1998). Neural pathways that are being used repeatedly add capacity,
like electricians adding wiring to the circuits in a building that the occupants
use most frequently.
If we practice an action repeatedly, for instance, our tennis serve, we add
capacity to the neural bundles that carry the information required to complete
this action. If we think the same kind of thought, perhaps “I hate my job,”
repeatedly, we also add capacity to the synaptic connections responsible for
carrying that information through our brains.
Our wise bodies notice which information-processing channels we are using,
and increase their capacity. While this phenomenon had been noted in earlier
research, the sheer scope of the rewiring operation—a doubling of capacity in
just one hour—was astonishing. Kandel’s work resulted in a well-deserved
Nobel Prize for medicine in 2000.
Intrigued by the speed at which the body lays down new lanes in the information
superhighways of the brain, the next research question presented itself
naturally to Dr. Kandel. If our bodies are assembling arrays of molecules to bulk
up oft-used neural bundles, what happens to bundles we aren’t using? He found
that unused neural pathways atrophy.
Just as efficiently as it wires in new connections along frequently used channels,
our bodies disassemble stretches of neural networks that aren’t being used. In
the parsimonious economy of the brain, nothing is wasted. Roads that aren’t
being used are torn apart, freeing those molecules for the construction of new
capacity in frequently used highways.
The speed of demolition was as surprising as that of construction. Kandel found
that, within two weeks, unused neural bundles start to be disassembled.
The implications of this are profound. Imagine that you have the option of
thinking positively or negatively about your job. You can tell yourself positive
stories or negative ones, and either of them can affect the structure of your
brain.
If you think a negative thought repeatedly, you literally rewire your brain. Same
with a positive thought. Henry Ford was no neuroscientist, but his famous
maxim foreshadows the work of pioneers like Kandel: “Whether you think you
can, or think you can’t, you’re right.” Chiropractor Joe Dispenza, in his book
Breaking the Habit of Being Yourself, stresses that we have to build the neural
wiring to perceive a positive reality, in the absence of material evidence of that
reality, in order to be able to perceive that reality when it shows up (Dispenza
2012). If we haven’t built the neural capacity to perceive it, we don’t see our
desired reality even when it’s right before our eyes.
Neural plasticity works for us or against us. When a stroke victim regains full
function by rewiring around the areas of the brain damaged by the stroke, or
when a positive thinker rewires her brain to perceive a positive outcome, we use
neural plasticity to our advantage. That’s the light side of the phenomenon.
There’s a dark side to neural plasticity. When the negative thinker repeats those
thoughts hundreds of times, for thousands of days, that person reinforces
corresponding pathways in the brain. On the brighter side, scientific work in the
field of memory reconsolidation shows that there are periods during a
therapeutic experience when a window of “lability” opens up, and long-standing
behaviors can be disrupted. Once the association between a traumatic memory
and the body’s stress response is broken, it stays broken. Neural networks then
begin to rewire themselves to carry new and more supportive behaviors and
thoughts.
The realization that we can rewire our brains, both creating new neural
pathways, and disassembling old ones, gives us phenomenal power as
individuals. You may not be able to change the objective facts of your childhood,
but you can certainly change the subjective frame through which you see them.