An Introduction to Neuroplasticity
Neurons are cells that are part of the central nervous system and are responsible for carrying messages between the brain and other parts of the body, as well as to and from different parts of the brain. They are responsible for the most basic to the most complex actions of our bodies, from our conscious thoughts and memories to our automatic reflex actions. The average human brain contains about 86 billion neurons, and each one is connected to around 1,000 others, creating an incredibly vast communication network.
Neurons ranging in size from a fraction of an inch to three feet communicate with each other by firing electrical impulses that travel from cell to cell. Information is passed through the tiny space between them (a synapse) when chemicals called neurotransmitters are released and absorbed. There may be as many as 100 trillion of these connections in an adult brain. Each neuron might receive input from thousands of others before firing its own signal. The more often the connections between specific neurons are activated, the stronger the attractions become among them. The pathways formed and the strength of the connection during communication are what are important in learning, memory, and recovery from a brain injury.
Neuroplasticity allows changes in the structure of neurons, the strength of neural connections and pathways, and the physical structure of the brain. It can even cause the creation of new neurons (neurogenesis).
Examples of Neuroplasticity in Action
Learning to walk
Consider what happens when a baby learns to walk. They try and fail repeatedly, but sometimes they succeed in keeping their balance, taking one step and then another. Eventually, they learn to walk and rarely fall. Each time a baby successfully takes a step they are using the same neural pathways. In other words, the same neurons work together to send effective messages to different parts of the body. Through repetition, those particular paths and neurons are strengthened and the connections are more likely to be repeated. This process is known as Hebbian theory and spawned the phrase, â€œWhat fires together wires together.â€ As those pathways for successful walking are used more often, the other pathways, which resulted in the baby falling, are used less often, so the connections between those neurons weaken or disappear. This â€œuse it or lose itâ€ process is called pruning, and it is also an important part of successful development.
The example of a baby learning to walk is neuroplasticity in its basic form. This is what we call learning, and it is just the tip of the iceberg when it comes to understanding the power of the human brain.
Recovery after a brain injury
Neuroplasticity can allow the brain to compensate for loss of function after a brain injury. It cannot revive dead tissue there, but it can create new pathways around the injury and restructure parts of the brain to serve new purposes. A dramatic example is a surgical procedure called a hemispherectomy, where one hemisphere of the brain is removed. It is generally performed when a child experiences continual, life-threatening seizures. After successful surgery, the remaining hemisphere of the brain is able to almost fully take over the functioning of the other. With a great deal of therapy, patients are able to relearn language that may have been lost, regain motor function, and live a healthy, seizureâ€‘free life.
Changes related to sensory loss
Brain reorganization also occurs in response to sensory loss. Studies of people who are blind show that their visual cortexes can be rewired to process language and tactile input instead of visual information. One example is when someone who is blind learns braille. Their visual cortex is activated as they use their fingertips to read. The same phenomenon can occur in people who lose their hearing. Their auditory processing center can be repurposed for visual and tactile processing.
Connection with autism
Neuroplasticity can be a positive influence on a personâ€™s quality of life, cognitive development, and memory, but it also can have adverse effects. For example, in the brains of some people with autism, it is thought that pruning does not take place the same way it does in typical brains. Some people with autism have more pathways because of this, which may result in the savant skills we sometimes see in those individuals. It is thought that these extremely well-developed skills come at the expense of other important ones, like communication.
What Can Enhance Neuroplasticity?
Adequate sleep is important for neuroplasticity.
Dopamine is a chemical made by our bodies that plays a role in how we feel pleasure. Too much or too little can adversely affect a person. For example, individuals with ADHD and Parkinsonâ€™s disease have too little, and those with drug addiction and schizophrenia have too much. Dopamine is an important neurotransmitter because it can strengthen synaptic connections. But, too much or too little released or absorbed by neurons that are sending impulses to one another can dramatically impede neuroplasticity. Fortunately, dopamine levels can be modulated with medication. People recovering from a brain injury are sometimes prescribed dopamine.
Music can be a facilitator of neuroplasticity. Listening to, moving to, and making music all seem to be important. Musicians who practice many hours a day for years have larger and denser temporal lobes in their brains. But music processing is not confined to just the temporal lobe; music targets neurons in several areas of the brain, and this seems to be significant in neuroplasticity. An important goal in music therapy is to synchronize neural activity. Pairing music with guided breathing, motor movement or vocalization may elicit simultaneous firing of neurons involved in controlling those behaviors, thereby strengthening neural pathways. Rhythm and melody are processed in different areas of the brain and can improve both motor movements and language development when they are used in teaching or therapy.
Music can also activate production of dopamine. Recent research in music therapy for individuals with autism supports music as a powerful intervention. One interesting study shows that some children with autism respond to directions sung but not spoken to them. The latest report from the National Clearinghouse on Autism Evidence and Practice added music therapy as an evidenceâ€‘based practice.
Exercise releases a protein called brain-derived neurotrophic factor (BDNF) that supports formation of neural pathways. Exercise can also stimulate production of dopamine. Like music, pairing exercise with other behaviors can cause a synchronized effect that strengthens neural pathways and can lead to faster and more-permanent changes in the brain. Studies have shown that exercise can also increase neurogenesis in the hippocampus, which is involved in memory storage.
What Can Impede Neuroplasticity?
Stress plays a major role in reducing neuroplasticity. It causes the release of the hormone cortisol, which can cause neurons to atrophy, inhibit formation of strong connections between neurons, affect the formation of new neural pathways, and ultimately hamper memory, motivation, and the ability to learn.
Over-prompting by teaching staff, parents, or therapists can result in learned helplessness, which can have the same damaging ramifications as stress.
Sleep deprivation is interpreted by the brain as stress.
Drug addiction causes overproduction of dopamine that inhibits neural communication.
Noise that is meaningless and feels unpleasant has the opposite effect of musicâ€”it impedes neuroplasticity.
Depression has been shown to be detrimental in several ways to neural activity, but antidepressants can restore neuroplasticity in people with that condition.
Tips for Teachers, Therapists, and Parents
Focus and attention
Teach and practice a variety of stress-reduction techniques.
Prepare engaging lessons and therapeutic activities. When students are motivated and attentive, their brains release dopamine.
Reduce extraneous and meaningless noise during lessons and therapy sessions.
Allow or encourage adequate sleep. Extra sleep is especially important for people recovering from a brain injury.
Incorporate music into lessons and therapy sessions. Pairing melodies and rhythmic drumming with language instruction, imitation, and memorization tasks can benefit many students. Use music as a relaxation or stress-reduction technique and to regulate breathing.
Incorporate rhythm, movement, and dance into lessons and therapy sessions. Bouncing on a ball while learning language skills or jumping on a trampoline when rehearsing spelling words are examples. Marching and rhythmic movement may regulate emotions and reduce stress.
Consider joint therapy sessions. When speech and occupational therapists work together, they often find that movement increases vocalizations.
Use sufficient repetition when teaching academic, language, and motor skills.
Nurture a growth mindset in children by helping them to understand that their brain can change and become stronger.
Avoid over-prompting. Provide the least amount of prompting necessary for a student to accomplish a task that they cannot quite do easily on their own.
Consider extended school-year services for new braille users. If an emergent braille user stops using it, like a student might do over a long school break, neuroplasticity is reversed and the skill is weakened.
There is a lot that we know about neuroplasticity, but more that we donâ€™t know. The field of neuroscience is ever changing, and neuroscientists will continue to give us information that will help us gain a greater understanding of how to harness the remarkable power of the human brain. As educators and lifelong learners, we have a responsibility to keep abreast of new developments in the area of neuroplasticity and its implications for teaching and learning.