Teaching an old dog new tricks. Learning how to balance a broom on your nose. Recovering from an injury or trauma. Improving long-standing or persistent pain. What do all of these have in common?
This incredible biological process allows us to change. Change who we are. Change what we can do. Adapt and improve after injury.
What is neuroplasticity?
Defined: “The ability of the nervous system to change its activity in response to intrinsic and extrinsic stimuli by reorganising its structure, functions, or connections.
The neurons of the nervous system possess an ability to modify the strength and efficacy of their synaptic transmission through a range of activity-dependant mechanisms (more on this to come).
Although we have a basic genetic “blueprint” to guide the development of our brain and behaviour, we are shaped from a wide range of experiences.
When a brain is exposed to different environmental events such as sensory stimuli, stress, injury, diet, drugs, and social relationships, the development trajectory becomes uniquely individualised.
**Interestingly, this fundamental function of the nervous system exists in species from insects to humans**
Video: click this link for a YouTube clip describing neuroplasticity.
Types of plasticity:
Here’s where it could get a bit heavy so I have done my best to summarise because it really is a fascinating concept (well, we think it is anyway).
The first type of plasticity is called Experience-independent plasticity. This is pre-natal development process where the brain produces a rough structure and over produces neurons for connections to be sculpted later in response to internal and external events.
The second type is Experience-expectant plasticity. This is the normal, generalised development of neuron connections that occur as a result of common experiences that all humans are exposed to in a normal environment. These early universal experiences are visual stimulation, sound (specifically voices), and bodily movement. So essentially this is still a developmental phase.
Finally we have Experience-dependent plasticity. This is the one we’re focussing on as this refers to a process of changing neurons that are already present!
So what is affected when we think about neuroplasticity?
The brain contains 98% of our nervous system, made from billions of neurons. Neurons communicate with other neurons via a synapse (see the image below for a representation of what a synapse looks like)…
Neurons carry information in the form of an electrical impulse called an action potential that is initiated at the cell body and travels down the axon (see image below in the “what changes are taking place” section). At the synapse, an action potential causes a release of neurotransmitter-filled vesicles and the electrical signal is transformed into a chemical one. There are small receptors on the receiving synapse waiting to receive this chemical information (the neurotransmitter-filled vesicles). The reverse happens whereby the chemical signal received is then turned into an electrical signal once again.
Neuroplasticity is the ability to modify the strength of existing synapses, as well as form new synaptic connections (note: there can also be elimination of synapses in adult and developing brains. This is how we can “unlearn” habits e.g. reducing persistent pain).
Neuroplasticity also includes new growth of neurons following an injury to the central nervous system.
What changes are taking place with neuroplasticity?
Change to our neural tissue is divided into functional and structural.
Functional changes take place at individual neurons.
Structural changes take place at synapses, within neurons or within glial cells (a huge portion of cells that make up the “white matter” of the brain such as those responsible for the blood brain barrier).
Physiological changes associated with neuroplasticity include:
- An increase in the number and density of receptors on the post-synaptic cell
- Larger, thicker synapses (this larger size is more likely to trigger an action potential)
- Formation of new dendritic trees into denser or grouped patterns
- Increasing the number of individual synapses
- Increasing the density of grey matter
- Increasing connection between two adjacent synapses
Does this change with age?
It was originally believed that our brain stopped changing when we hit peak growth or maturity. But this simply isn’t the case. Generally, young brains tend to be more sensitive and responsive to experiences than much older brains. But this doesn’t mean that adult brains are not capable of adaptation. Our brain has a lifelong capacity to change and rewires itself in response to the stimulation of learning and experience. However, there is a decline in the rate of neuroplasticty as we age.
Here are a few tips (there are a lot more) specific to neuroplasticity and delaying the neurological effects of ageing with exercise/activity:
1. Maintenance of neural mechanisms is dependent upon use and thus lack of biological activity to stimulate such mechanisms can lead to functional degradation – use it or lose it
2. Use and training can drive enhancement in the function and structure of specific neural mechanisms – use it and improve it
3. The training experience must match the desired outcome; the nature of neuroplasticity is dictated by the nature of the training – be specific
4. Learning requires repetition, progressed in difficulty and spaced over time – repetition is essential
5. Plasticity changes require a sufficient training intensity to endure durability of pathways – intensity matters
So what does all of this actually mean for you?
Neuroplastic change is possible at any age. This includes the ability to learn new activities, skills or languages.
Recovery from injury is possible, for example rehabilitation from a stroke can reverse some of the effects caused by damage to specific areas of the brain using neuroplasticity.
Practice really can make perfect (well, technically not as perfect as the 10,000 hour rule dictates, let’s rename it the 728 to 16,120 hour rule).
Your genetic makeup, when you start, and how you learn all combine to determine how many hours it would take you to master a specific craft – or if “mastery” is possible at all.
However, giving it a try will be far more beneficial than not, so why wait?
P.s. if you’ve made it this far, thank you. You get the reward of clicking on the link below to learn more about neuroplasticity without even having to move a muscle… enjoy!