Introduction
The idea of neuroplasticity, or the theory that the brain continues to learn and develop much into our adult life and does not stay fixed or shrink, was introduced almost 200 years ago. And then, throughout the years, it has been studied, debated, and even wholly denied as a possibility.
Until the mid-nineteenth century, scientists were often ridiculed or completely ignored for conducting new research in neuroplasticity. It was not until the last decade of the century, after the discovery of neural stem cells in adult brains, that the scientific community agreed collectively that the brain is capable of growth. We learned you can, in fact, 'teach an old dog new tricks.'
Some of us have heard the term neuroplasticity, but most have heard a more popular phrase, "rewire your brain". It is commonly discussed in self-help books, TED talks, or by motivational gurus. They state that you can unlearn depression or anxiety by expanding your mental state through simple things like mediation or even learning a new language. We have scientific proof that you can rewire your brain and continue learning new things until late in life.
The following article covers my top takeaways from the MIT Essential Knowledges Series on Neuroplasticity by Moheb Costandi, a molecular and developmental neurobiologist. We will dive deeper into what neuroplasticity is and its fundamental findings in neuroscience.
What is Neuroplasticity?
Neuroplasticity is the brain's ability to reorganize itself by forming new neural connections throughout life. Neuroplasticity allows the neurons (nerve cells) in the brain to compensate for injury and disease and adjust their activities in response to new situations or changes in their environment.
All types of neuroplasticity involve changes in neurons' structure and function. The three main types of neuroplasticity are:
Brain reorganization that occurs during the learning of a specific task.
Brain reorganization in response to injury.
Brain reorganization that takes place during the normal aging process
Cross-Modal Plasticity
Cross-modal plasticity falls under the categories mentioned above in neuroplasticity. It is the brain's ability to reorganize and make functional changes to compensate for a sensory deficit or injury.
Beautiful Examples of Cross-Modal Plasticity
Paul Bach-y Rita created a device that uses electrical pins in one's back to create a series of light sensations allowing blind people to visualize and recognize their surroundings. For example, common household objects and even being able to tell the difference between people based on their facial features.
According to Costandi, the author of this MIT Essential Knowledge Series, he wrote," Bach-y Rita argued that this ability was due to "cross-modal" mechanisms. Whereby information that is normally conveyed by one sense, such as vision, is somehow transmitted and conveyed by another, such as touch or sound."
The FDA approved a more modern device in 2015 called the BrainPort V100. Instead of connecting the pins to one's back like in the Bach-y Rita chair device, the BrainPort V100 uses micro pins to the tongue.
Synesthesia is a rare phenomenon that occurs in some people, where the person can visually see colours attached to words, letters, or sounds like music or names of people. What is truly remarkable is that non-synesthetes can learn to associate letters with colours or sounds similarly through training, which is a result of cross-modal plasticity.
Long-Term Potentiation and Long-Term Depression
Another area of neuroplasticity that is the most studied and, therefore, the most understood is the area of Long-term potentiation (LTP). In neuroscience, LTP is described as a persistent strengthening of synapses based on recent patterns of activity. Synapse is a small gap at the end of a neuron that allows a signal to pass from one neuron to the next. LTP is thought to be how the brain changes in response to an ongoing experience and could be directly related to learning and memory.
The opposite of LTP is long-term depression, which produces a long-lasting decrease in synaptic strength, making neurotransmission less effective. LTP could be responsible for a decrease in memory and make it harder to focus on learning new tasks.
Rewiring Your Brain
We must be cautious with the term rewiring your brain. There are many companies out there who claim that their products can help rewire your brain or improve your life. For example, playing sudoku every day might not improve your overall mathematics skill, but it will undoubtedly improve your sudoku skills.
We know, however, that we can do simple daily tasks to improve neuroplasticity. Costandi writes, "Certain environmental factors can regulate the process to dramatically affect the rate at which new neurons are produced. For example, physical activity, environmental enrichment, and learning tasks enhance the proliferation of neural stem cells and, in some cases, promote the survival of newborn neurons, whereas stress, certain types of inflammation, and sensory deprivation have the opposite effect."
Transfer Effects
In neuroscience, the term transfer effects describe individuals' ability to use the knowledge and skills learned in one scenario to achieve different goals in other scenarios in their daily life. For example, learning to meditate can calm your mind in the moment, but it also has a transfer effect of being able to change your response to future stressful situations.
Brain Training Games
There is little evidence that brain training products lead to transfer effects. Companies claiming their products can 'stop' cognitive decline have serious repercussions.
Lumosity, a brain training game, claimed it could help users perform better at work and school and reduce or delay cognitive impairment associated with age and other serious health conditions. In 2016, Lumosity was ordered by the U.S. Federal Trade Commission to pay $2 million for deceiving customers.
Learning a Language or Lifelong Skill
Studies have found that bilingualism is associated with an increase in gray matter, especially in a person who uses multiple languages constantly throughout their lives. Even in the short-term learning of a language, the gray matter is increased, but it will also decrease when the person gives up on learning the second language.
Constandi states that "learning a second language is associated with other kinds of anatomical changes, including changes in the cortical thickness in brain areas linked to language, as well as changes in the architecture of the white matter tracts that interconnect them." Unlike brain training games, there is evidence to support that lifelong bilingualism does appear to have transfer effects. Similar transfer effects can be found in learning an instrument or other skills and continuing that practice throughout one's life.
Closing Remarks
A ton of evidence supports neuroplasticity and suggests that the brain is highly flexible. With current technology, we are only beginning to truly understand how our brain adapts to environmental, physical, and emotional changes. As new technologies emerge, we will see highly sophisticated ways of imaging the brain that will deepen our knowledge and uncover new revelations of one of the most fascinating, advanced, and yet still wildly misunderstood organs of the human body.
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