written by: kirsten yip
graphics by: yunyi cui
From the moment we’re born, our lives are dynamic and constantly changing. Every day presents something new and we’re constantly striving to “live life to the fullest” (or just keep up with it, to be honest). One thing that remains essential as we move through life is our ability to adapt, learn and recover. Every time we learn something new, physically or mentally, we are capitalizing on the power of neuroplasticity.
You might have heard the term neuroplasticity before, as this developing field has made its way into wellness apps, learning centers, rehabilitation centers, and even athletic performance. “Neuro” means that it involves the nervous system, which consists of the brain, spinal cord and all of the nerves that send information to and from the brain. “Plasticity” comes from the Greek word “plastos”, which means moldable. So, neuroplasticity directly translates to “a moldable brain.” (1) It’s a way to describe the functional and structural reconfigurations that are made in the brain that facilitate adaptation, learning, memory, and rehabilitation after a brain injury. (2) These reconfigurations range from molecular, synaptic, and cellular changes, to more global network changes. (3) As long as you’re alive, regardless of age or health, the brain can make new connections and improve its performance and health. (1) In other words, as we grow, live, and experience new events, our brain is changing with us every single day too!
Our central nervous system is innovative with its synaptic communications between neurons. The brain is biologically prepared to learn. It contains about 86 billion neurons, which are specifically organized into different areas. (2) Due to its plasticity, the large organ inside of our skull can physically and functionally change. These changes are experience-dependent; they happen in response to an environmental stimulus, cognitive demand, or behavioural experience. (4) For example, when we are learning something new, we’re exposing ourselves to a specific stimulus repeatedly, usually with intensity; when you’re studying new biology concepts or learning to ride a bike for the first time, you’d be focused on the task at hand and practicing over and over again. This repetitive practice stimulates neural pathways to form new synaptic memories and strengthen the existing synaptic communications, which allows us to eventually retain that new information or skill. (1, 5)
This adaptive “rewiring” or “re-organization” is a result of biochemical processes in synapses and other neuronal compartments. It primarily occurs through processes called sprouting and rerouting. Sprouting is the creation of NEW connections between neurons, or nerve cells. Rerouting is the creation of an alternative neural pathway by removing damaged neurons and forming new pathways between active neurons. (5)
The process of sprouting and rerouting has shown to increase grey matter density and white matter integrity. (1) This is important in promoting strong communication within our central nervous system, which involves the brain and spinal cord. Grey matter contains neuron cell bodies to enable control of movement, memory, and emotions. Grey matter is located in the brain and the spinal cord. Different areas of the brain are responsible for different functions, but grey matter plays a significant role in every aspect of human life. (6) White matter lies beneath the grey matter cortex and contains millions of bundles of myelinated axons. These axons transmit information from neurons in different brain regions into functional circuits. (7) You can think of them like long, extending telephone communication lines, which are responsible for the smooth operation of the nervous system.
While neuroplasticity makes the brain extremely resilient and adaptable, it can also make you vulnerable to extreme influences. (2) If the brain re-trains itself in response to a persistent negative behaviour or stimulus, it can inflict trauma by strengthening unhealthy pathways. (5, 8) This change is referred to as “negative neuroplasticity”. Chronic stress, anxiety, and depressive-like behaviours have been associated with impairments in neuroplasticity, such as neuronal atrophy and synaptic loss in specific areas of the brain (e.g. the hippocampus, which has a major role in learning and memory). (9) This occurs because chronic stress leads to sustained decreases in the expression of neuroprotective factors; this results in deficient adaptation to the environment, compromising learning and stress coping. Patients with depression present reductions in gray matter volume in their neuroimaging. This displays evidence of negative neuroplasticity—remember how we said that positive neuroplasticity increases gray matter?
But don’t let this information overwhelm you. Treatment plans that consider neuroplasticity enhancements might be valuable in overcoming this deficit. Exciting results suggest rapid acting antidepressants, physical exercise, and learning can facilitate positive neuroplasticity…
Essentially, neuroplasticity occurs naturally as we encounter different experiences. This means that these changes in the brain can also be activated intentionally through neuroplasticity-focused exercises and cognitive training. Training your brain is a step-by-step process. Similar to physical exercise, you can’t just jump into lifting the heaviest weights in the gym on day one. In general, activities that help maintain and/or increase neuroplasticity fall into two categories: (5)
New experiences: novelty establishes new neural pathways
Massed practice: heavy repetition of a certain skill or activity strengthens neural connections
Some cool exercises that can help in reducing anxiety:
Yoga and meditation: Practicing yoga has been associated with decreased stress levels in the amygdala, the fear center of the brain.
Physical activity: Physical activity has beneficial effects on executive functioning and memory. (10)
Sleeping: While not traditionally considered an exercise, sleep helps with learning and memory retention by transferring information across cells and growing connections between neurons.
Ultimately, it’s truly amazing how our brain is innately ready to adapt, learn, grow, and recover to carry us through the ups and downs of life.
Glossary
Synapse - the site of transmission of electrical nerve impulses between:
Two nerve cells (neurons)
A neuron and a gland or muscle cell (effector) (11)
Myelinated axon - an axon that has an insulating, or sheath, around it to allow for quicker and more efficient transmission of electrical impulses
References
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Alina F. Neuroplasticity Treatment: How It Can Help You Recover From a Brain Injury [Internet]. Post-Concussion Treatment Center. Cognitive FX; 2019 [cited 2021, Mar 16]. Available from: https://www.cognitivefxusa.com/blog/neuroplasticity-treatment-for-concussions
Price RB, Duman R. Neuroplasticity in cognitive and psychological mechanisms of depression: an integrative model. Mol Psychiatry. 2020 Mar;25(3):530–43.
Kraus C, Castrén E, Kasper S, Lanzenberger R. Serotonin and neuroplasticity – Links between molecular, functional and structural pathophysiology in depression. Neuroscience & Biobehavioral Reviews. 2017 Jun;77:317–26.
The Editors of Encyclopaedia. Synapse [Internet]. Encyclopædia Britannica. Encyclopædia Britannica, inc.; 2011 [cited 2021Mar16]. Available from: https://www.britannica.com/science/synapse
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