Neuroplasticity

Sculpting in a Hurricane

Your brain - every brain - is a work in progress. It is 'plastic.' From the day we're born to the day we die, it continuously revises and remodels, improving or slowly declining, as a function of how we use it.

- Dr. Micheal Merzenich

For many years, conventional wisdom assumed that learning ended in adulthood, that the brain became a hardened thing. Modern research has shown that it continues to be moulded through life, just like clay on a potter's wheel. 

While the you or I can shape our brain through deliberate thought and action, the environment we are in plays a big part in how it gets shaped. Imagine the roof is blown off that same potter's studio, the sculptor is still at it shaping the clay, but now the strong winds and rains form it as well. 

 

As our thoughts and actions are repeated over time, they can form habits. These automatic processes run in the background of our minds allowing our brains capacity to navigate new situations.

 

Depending on how much habits run your life, you could say that our character rests on our automatic response to the world around us. Whether they are good or bad habits depends on their contribution to what is really important to you.

 

We will be exploring how we can uncondition ourselves, to take a deep breath and say "ah, that's a habit i picked up when I was younger to get me through this tough time, and it is now hurting my relationships". By becoming aware of the automatic, we have the chance to change.

The patterns of activity of neurons in sensory areas can be altered by patterns of attention. Experience coupled with attention leads to physical changes in the structure and future functioning of the nervous system. This leaves us with a clear physiological fact…moment by moment we choose and sculpt how our ever-changing minds will work. We choose who we will be in the next moment in a very real sense, and these choices are left embossed in physical form in our material selves.
 

- Dr. Micheal Merzenich


We have the power to change our brains, and so does the environment that we surround ourselves with. Neurons that fire together wire together, and stepping back can be imagined as intricate maps, linked by networks of pathways that ebb and flow as the years pass.

This is where action comes in, the maps are strengthened or weakened based on the quality and depth of repetition. Riding a bicycle can be hard initially, as we have to work on balance, motor control, spacial awareness and others just so we don't fall. With enough practice, balancing on two wheels and enjoying the freedom of riding is ecstasy. Falling is part of the learning.

 

For some, they never get back on. All that progress made will fade as the map in the brain is slowly replaced. Gerald Edelman proposed that there is “neural Darwanism,” happening within the brain also known as competitive plasticity. When learning a skill, people can recruit operators devoted to other activities to help them master it. However, stop practice and you lose what you gained. How much you lose is dependent on how much you started with. Use it or lose it. 

For those who keep at it, fewer neurons are required to do the work, the brain maps become more precise and the who system works more efficiently. Moving closer toward mastery, the skill becomes second nature. If you've ever seen a bicycle messenger fly through rush hour traffic while shouting into a phone, you know what I'm talking about. 

Maguire et al. (2000) examined the brains of taxi drivers in London to evaluate whether their work would result in structural brain changes as compared to control groups. London's streets are particularly to master given the hundreds of years of seemingly random urban planning, full of arcane rules and one way roads. 

The brain scans of the taxi drivers showed a particularly large posterior hippocampus, a region of the brain that supports two-dimensional spatial processing, and this was even more evident the more experience the taxi driver had. The thousands of hours plying the streets had changed the very structure of the brain.

Being able to navigate the streets of London is a great skill, but sometimes practice can lead down a darker road. Getting high through experimentation with different drugs is caused by their activating of reward circuits in the brain. While it might initially be a voluntary behaviour, over time, the capacity to exert self-control can diminish leading to addiction. 

Not all neuroplastic change is positive. The forces that help learning can also reinforce addiction. The plastic paradox describes how the same neuroplastic properties that allow us to change our brains can ingrain rigid ideas. Practice makes perfect and becoming aware of our thoughts and actions takes on a new importance with this knowledge. 

 

"Neuroplasticity contributes to both the constrained and unconstrained aspects of our nature. It renders our brains not only more resourceful, but also more vulnerable to outside influences." 

- Norman Doidge


Not all structural changes happen by deliberate practice. A stroke cuts off oxygen to certain areas of brain tissue. Once the damage is done, the hope becomes to rewire maps from the dead tissue to a neighbouring area to try and recover some function. This plays out in the brain through the deliberate creation of new pathways that aim to replicate or substitute those which are no longer available.

Imagine watching slow and steady commuters driving across a bridge during rush hour. They have done this countless times before, and are just making their way to work. If the bridge collapses overnight, each driver tries to find an alternate path to where they are going. Some get their faster, some are hopelessly late. Now assuming the bridge cannot be repaired, eventually all the drivers will find the next best route to get to work. When key pathways are blocked, through the right therapy and training the brain can find ways around them. 

With enough time and deliberate practice, research has shown that some recovery can be achieved. However, the same forces that allow for this rewiring can also form powerful walls that prevent growth and development - the plastic paradox. 

It is how they are using their plastic brains, which is actually reinforcing the rigid behaviours. This is the “plastic paradox” — that the same plasticity that can give rise to flexible behaviours, can also give rise to rigid ones, depending upon how it is engaged by the client.

- Norman Doidge

Let's explore this looking at a basketball player, who is good, but not exceptional. Thinking can be a disadvantage to reaction time in a fast paced game, so when a player performs the shot automatically, it actually expresses the developed neural pathway that is operating at a speed quicker than thought. 

 

Let's say that this player has a problem with 3 pointer shots, that must be taken from a distance and with high accuracy. Every time his poor technique is repeated, the brain maps it onto the motor pathway. If the basketball player finds a coach that is able to show him a better way to take the shot, he will need time to 'unlearn' the bad habits which have become engrained, and then learn to remap his brain with the proper form through practice. 

“Among other things, neuroplasticity means that emotions such as happiness and compassion can be cultivated in much the same way that a person can learn through repetition to play golf and basketball or master a musical instrument, and that such practice changes the activity and physical aspects of specific brain areas.” 
 

― Dr. Andrew Weil

The brain does lose some cognitive ability as we age.   Below, aging data showing performance of speed of processing, working memory, long-term memory and world knowledge are captured and explained: 

Almost all measures of cognitive function show decline with age, except world knowledge, which may show improvement. There is evidence to support that the brain's ability to change helps people to function at a considerably high level as they age. Dennis & Cabeza (2008) demonstrated how the brain responds to ageing by expanding its activity or by recruiting new sites of activation to process the world around it. This ability to maintain, expand and even retarget function is the essence of neuroplasticity. 

"Plasticity dials back ‘ON’ in adulthood when specific conditions that enable or trigger plasticity are met. ‘What recent research has shown is that under the right circumstances, the power of brain plasticity can help adults minds grow. Although certain brain machinery tends to decline with age, there are steps people can take to tap into plasticity and reinvigorate that machinery. These circumstances include focused attention, determination, hard work and maintaining overall brain health."


- Dr. Michael Merzenich

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References:

The Brain That Changes Itself: Stories of Personal Triumph from the Frontiers of Brain Science. New York: Viking, 2007. Print - Doidge, Norman.

Soft-Wired: How the New Science of Brain Plasticity Can Change Your Life. Print. - Dr. Michael Merzenich

Spontaneous Healing : How to Discover and Embrace Your Body's Natural Ability to Maintain and Heal Itself - Andrew Weil 

The aging mind: neuroplasticity in response to cognitive training Denise C. Park,

Sixty minutes of what? A developing brain perspective for activating children with an integrative exercise approach.  Myer GD, Faigenbaum AD, Edwards NM, Clark JF, Best TM, Sallis RE. (2015)

The Effects of Cognitive Training for Elderly: Results from My Mind Project Cinzia Giuli,corresponding, Roberta Papa, Fabrizia Lattanzio, and Demetrio Postacchini

Dennis NA, Cabeza R. Neuroimaging of healthy cognitive aging. In: Craik FIM, Salthouse TA, editors. The Handbook of Aging and Cognition. 3rd ed. Psychology Press; New York, USA: 2008. pp. 1–54.