Neuronal plasticity, or neuroplasticity, is the biological process by which the brain reorganizes its synapses in response to stimuli. The brain always aims to optimize its functioning, and because of this, there are biological systems in place which frequently enhance engaged-in patterns of thinking, making relevant neural networks stronger, and irrelevant ones weaker, supporting processes such as learning and memory.
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The study of the underlying biological mechanisms of neuroplasticity has proven invaluable to helping scientists understand not only how learning and memory occur in the brain, but it has also provided a model for some neuropsychiatric disorders and essential insights on recovery after brain injury. Because of its implications in these key areas of mental health, neuroplasticity is considered to be an important area of study.
What is neuronal plasticity?
Neuroplasticity refers to the biological process whereby the brain's activity and responses to stimuli influence the strength or weakness of specific synapse to synapse connections or even grows new connections.
This synaptic plasticity culminates in neuroplasticity, as the strengthening of relevant and weakening of irrelevant connections allows the brain to respond dynamically to a myriad of situations and help it to become efficient and responding to repeated stimuli.
These changes within specific synapse connections contribute to amendments in larger neural networks that may be responsible for distinct functions. For example, these neural networks may determine how we behave in certain scenarios, and they may form as a result of learning or help us to create memories. Neuronal plasticity has also been implicated in various neurological disorders, and mounting evidence is showing that the dysfunction of this mechanism may result in various pathologies.
The significance of neuroplasticity
Neuroplasticity is incredibly important because it is at the root of essential human experiences. Learning and memory, key parts of what it means to be human, would not be possible without this process. In addition, the continued study of neuroplasticity is considered essential for furthering our knowledge of neuropsychiatric disorders and brain injury and will help lead to new and improved treatment options.
The significance of neuronal plasticity is illustrated well by studies that took place with Buddhist monks. A little over ten years ago, scientists worked with the Dalai Lama, who helped them to recruit Tibetan Buddhist monks for numerous studies into how meditation impacts the physical brain. For centuries this practice has been well known for its ability to impact the mind, but up until this point, there was little evidence showing how meditation could alter the brain's neural circuitry.
Numerous studies took place at the Waisman Laboratory for Brain Imaging and Behavior at the University of Wisconsin-Madison, and the findings were seminal. Scientists were able to prove that meditation could bring about physical changes in the brain, altering its structure and function. The results can be used as a sign of the potential of neuroplasticity, as the research highlights just how malleable the brain is, and how it is susceptible to change just through mental efforts.
Below, the role of neuroplasticity and the significance of studying it is outlined within various prominent areas of psychological research.
Neuroplasticity and depression
Impairments of structural plasticity have been implicated in the development of major depression. The research suggested that the effectiveness of antidepressants may, at least in part, be due to their impact on correcting impairments in structural plasticity.
Indeed, studies have shown that serotonin reuptake inhibitors (SSRIs) play a role in mediating development-like neuroplasticity. These findings imply that future treatments may be developed with this model of plasticity impairment in mind.
Neuroplasticity and learning
A growing body of research supports the role that neuroplasticity plays in learning. The ability of the brain to reconfigure makes the acquirement of new information and new skills possible. The brain must be impacted by this new information in order to learn it: the nature of learning is that we change through experience.
Neuroimaging studies have confirmed that anatomical changes take place in the brains of those learning a second language. These results show neuroplasticity at work, changing the structure of the brain to allow for learning to take place.
Neuroplasticity and stroke
Research has shown that the brain is entirely capable of responding dynamically to situations that allow it to make changes to its neural circuits. This is essential in recovery from brain injury, such as stroke. Studies have shown that neuroplasticity, in part, is responsible for successful recovery in those rehabilitating from a stroke.
Evidence strongly suggests that the best recovery outcomes are fostered by rehabilitative training, which boosts neuronal plasticity, helping patients' brains to regain functions through amending its circuitry. In increasing our understanding of this, scientists have the potential to develop new therapies that could help improve treatment outcomes.
Neuroplasticity and cognitive behavior therapy
Cognitive-behavioral therapy (CBT) has been shown to be at least as effective as medication in treating depression. It is also considered highly effective in treating anxiety disorders.
Recent studies have shown that CBT has the impact of physically changing the brain, highlighting the role of neuroplasticity in successful recovery from these psychological disorders. For example, one study found that those with anxiety disorders displayed increased activity in the amygdala. Following CBT, grey matter volume in this area decreased, as did neural responsivity. The findings supported that the success of CBT is related to the structural and activation changes that are brought about by neuronal plasticity.
Summary
The biological process of neuronal plasticity allows for changes in neural circuitry, which can amend the structure and function of the brain. These changes allow learning and memory to work properly, and deviations in its working are related to neuropsychiatric disorders. Studying neuronal plasticity is important due to its implications in the treatment of these disorders, plus its implications in the treatment of brain injury.
Sources:
- Davidson, R., and Lutz, A. (2008). Buddha's Brain: Neuroplasticity and Meditation [In the Spotlight]. IEEE Signal Processing Magazine, 25(1), pp.176-174. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2944261/
- Fuchs, E., Czéh, B., Kole, M., Michaelis, T., and Lucassen, P. (2004). Alterations of neuroplasticity in depression: the hippocampus and beyond. European Neuropsychopharmacology, 14, pp.S481-S490. www.sciencedirect.com/science/article/abs/pii/S0924977X04001269
- Li, P., Legault, J., and Litcofsky, K. (2014). Neuroplasticity as a function of second language learning: Anatomical changes in the human brain. Cortex, 58, pp.301-324. https://www.sciencedirect.com/science/article/pii/S0010945214001543
- Månsson, K., Salami, A., Frick, A., Carlbring, P., Andersson, G., Furmark, T., and Boraxbekk, C. (2016). Neuroplasticity in response to cognitive behavior therapy for social anxiety disorder. Translational Psychiatry, 6(2), pp.e727-e727. https://www.nature.com/articles/tp2015218
- Voss, P., Thomas, M., Cisneros-Franco, J., and de Villers-Sidani, É. (2017). Dynamic Brains and the Changing Rules of Neuroplasticity: Implications for Learning and Recovery. Frontiers in Psychology, 8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5649212
Further Reading
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