- Neuroplasticity is the ability of the brain to change its structure and function in response to an input.
- If damage occurs along a neural pathway, the brain will try to re-organise itself to reroute information along a non-damaged neural pathway. This is less efficient than the original, so messages can take longer to arrive at the destination.
- Kleim and Jones (2008) outlined ten principles of neuroplasticity. These are important to consider when planning treatment.
Millions of people have benefited from rehabilitation programmes based on the theory of a plastic (malleable) brain. While research is still ongoing in this exciting field, the current body of knowledge on neuroplasticity is already shaping therapeutic practices and is an essential concept to understand in the brain rehabilitation field.
What is Neuroplasticity?
Breaking the word down simply, we see neuron is combined with another familiar term, plasticity. Neurons are the nerve cells in your brain; plasticity describes something malleable or capable of being remodelled. Neuroplasticity can be defined as the ability of the brain to change its structure and function in response to an input.
In daily life, we repeat movements over and again; walking, talking, writing. The motions have become so ingrained in our brain that we don’t even have to try; we just do it. The pathway of electrical messaging is so efficient because it has travelled down the same route so many times.
If damage occurs along a neural pathway, the brain will try to re-organise itself to re-route information along a non-damaged neural pathway. This doesn’t happen overnight. It takes lots of practice and repetition to build up another neural pathway. Even when a new pathway is established, it is never as efficient as the original, so messages can take longer to arrive at the destination, which explains why people with brain damage become slower at movements, speech, and thinking and often report feeling tired.
For example, imagine you live in a lovely wooded forest. To get water, you have to trek to a well, which is over a kilometre from your home. The path there is so well-trodden that it’s usually an easy walk. One day, a big storm causes several large trees to fall across the path, blocking it completely. You have to find a different way to get to the well. As you forge a new route, you tread through long grass, go off course a few times, and it’s generally hard work. However, the more you use the new route, the easier it becomes. It’s not quite as quick or efficient as the original path, but you find a way to reach the well. This is generally what the brain does when making new neural pathways.
Neuroplasticity: The 10 Principles (Summarised)
So how do we make use of neuroplasticity? Kleim and Jones (2008) outlined 10 principles of neuroplasticity which are handy to keep in mind. Here’s a summarised version:
- ‘Use it or lose it’ – When we fail to (either by laziness or because some trauma disallows us to) use a certain neural pathway, it will degrade over time. You can probably find examples of this in your own life: say you have just returned to college after several years in the professional world, only to find that your study skills may not be what they once were. So keep using the same neural pathways to prevent deterioration.
- ‘Use it and improve it’ – Study into neuroplasticity shows us that this principle of ‘use it or lose it’ can be extended to ‘use it and improve it’. ‘Training that drives a specific brain function can lead to enhancement of that function’ (Kleim and Jones, 2008). So, if you want to become a better piano player, public speaker or logical thinker, repeating behaviours is your winning ticket to success.
- Specificity – This relates to the training being specific enough to produce activation in a particular circuit. It’s important to stick to a regular training schedule. For example, if you wanted to strengthen the calf muscle, you would need to provide specific exercises to activate the calf muscle. Similarly, if you wanted to retrain someone’s attention, you need to ensure the task stimulates the attention system. Randomly surprising a person’s body with a weekly training session is less likely to produce positive effects than a consistent regime.
- Intensity – The intensity of training refers to how intense or engaging recovery training is. For neuroplasticity to occur, a certain intensity of training must be reached.
- Time – Results do not happen overnight, so the amount of time spent doing the activity is important. Structural and functional changes take time, and while ‘how much time until I get better?’ is the million-dollar question, the answer often varies from injury to injury and person to person.
- Age – Age will indeed play a role in how quickly one’s recovery advances. Children’s brains are naturally more plastic than older (and wiser) minds. There is a good reason for this: when we are young, flexibility is important as we take in and learn thousands of new things about the world each day. As we become more experienced, we sort the world into patterns which we know to be useful and these neural pathways become more efficient. The important thing is to simply be aware that age will play a role in the progress of a person’s recovery. Reassure older people that it’s okay if the recovery process takes time and that there’s no need to be frustrated by this.
- Engagement – What the recovery process means to the person can also have a significant effect on its success. There’s nothing worse than spending hours of your time on something you don’t care about. Emotional engagement and attachment within the recovery sessions can determine the strength of the training, and therefore its likelihood of success. The more important the recovery is to the person, the more likely they will be to remember the skills learned in the recovery process (Kleim & Jones, 2008). It’s just so OT!
- Transference and Generalisation – While the recovery process may happen in a controlled environment, it’s important to understand how these skills will be implemented in the real world. As a therapist, it’s important to plan a person’s treatment sessions in a way that will allow for this–training them in skills that can be transferred to situations the person will face outside of the therapeutic setting.
- Interference – If retraining is delayed after an injury, the person may have a set of learned behaviours, some good and some bad. The bad habits (like learned non-use) are a cause of interference in the recovery process, and a common resolution to this issue is to focus on un-learning harmful behaviours in an early recovery phase.
- Repetition – Neuroplasticity allows your brain to rewire itself in a way that will dedicate more brain cells to a specific task. The best (and perhaps the only sure) way to promote this is through repetition. Your brain is best at the things it does most often, so if you want to be good at something: repeat it.
Implementation in Practice
The natural follow-up question is, ‘How much repetition is enough?’. Taking hand and upper arm rehabilitation as an example, we see an average of 40-60 repetitions per session in standard therapeutic settings is sufficient to improve hand and upper limb function. When we compare this to what is required to make changes in the brain, it is well below what’s needed. Chau, Barbeau, and Rossignol (1998) for example, found that significant rewiring in animals took up to 1000-2000 repetitions per day. Other studies have put this figure at 400-600 daily repetitions for recovery training like fine motor grasping.
The takeaway is simple: the more repetitions the better. Without over-exerting a person or pushing them to the point of burning out prematurely, increasing the number of repetitions is the best way to strengthen the neural pathways for desired behaviour. Daily sessions may not always be possible, in which case you should encourage the person to continue their training at home – for the exercises that can be done alone. Otherwise, an every-other-day schedule is preferable, along with keeping training time slots consistent (if you always train in the morning, your brain will be more responsive to training in the morning!).
Neuroplasticity allows healthy, undamaged brain areas to take over previously learned brain functions, and repetition is key. The new pathways will never be as efficient as the original ones, but making use of the brain’s ability to rewire itself is essential in rehabilitation.
- Kleim & Jones (2008). Principles of Experience-Dependent Neural Plasticity: Implications for Rehabilitation After Brain Injury. https://www.jsmf.org/meetings/2008/may/Kleim%20&%20Jones%202008.pdf
- Rainbow Rehabilitation Centers. 2019. Neuroplasticity After Acquired Brain Injury – Rainbow Rehabilitation Centers . [ONLINE] Available at: https://www.rainbowrehab.com/neuroplasticity-aquired-brain-injury/.
- Doidge, N. (2007). The brain that changes itself: Stories of personal triumph from the frontiers of brain science. Viking Penguin: New York, NY.
- Flint Rehab. 2019. Massed Practice: Why High Repetition Is Excellent for Stroke Recovery. [ONLINE] Available at: https://www.flintrehab.com/2018/massed-practice/.