By Brian James Rose
Human brains are extraordinarily amazing. You might have heard stories about unexpected recoveries after traumatic brain injury, stroke, or other brain damages. But have you ever thought about how it happened? How does our brain accept and learn new things? Our brain can change or adapt itself in response to any change, disease, or injury. The neurons in the brain compensate to adapt to a changing situation or environment. Neuroplasticity or brain plasticity is the term used to define this brain reorganization in response to internal or external stimuli by forming new neural connections.
What is Neuroplasticity?
The term neuroplasticity is used to define the Brain’s reorganization throughout life by changing and forming new neural connections or by changes involving cortical remapping. Thus, we can say that the Brain’s ability to change itself is not limited only to the cellular level (neurons) but also on a larger scale (cortical). This reorganization occurs due to psychological experiences, new information, development, sensory stimulation, dysfunction, or damage. For example, the Brain changes itself when we learn new abilities, from surrounding socioeconomic influences, and when something has a psychological impact (stress, depression).
Earlier neuroplasticity was thought to be the process occurring in childhood. Later in the 20th-century, research studies have shown that the brain can alter itself even in adulthood. These biological changes in the brain occur as a result of our interaction with the environment. When the brain starts to develop in utero until the day we die, the cellular connections in our brains reorganize to adapt to our changing needs. It is due to this ability of the brain that we learn and adapt to different life experiences.
Neuroplasticity can also be understood by thinking of it as a muscle-building part of the brain. The things we do often (by repetition) we become stronger at. With every repetition of a particular thing, emotion, or thought, the neural connections or pathways are reinforced. This reinforcement is the basis of neuroplasticity, which is at work throughout our lives. Neural connections in the Brain constantly become weaker or stronger, depending on what is being used more or less. However, developing Brain changes easily as they are more plastic than the adult brain.
Mechanism of Neuroplasticity
The brain is developed in utero before birth, but its development continues throughout life, referring to developmental plasticity. For example, the infant relies on sensory and motor stimulation to develop new neural and synaptic connections. This developmental neuroplasticity in the developing brain is triggered by external stimuli and is based on learning and memory. It involves losing or making synapses, migration of neurons, or sprouting and rerouting of neurons. As the brain grows, the neurons become mature by making multiple synaptic connections (synaptogenesis). At birth, infants’ brains have around 2500 synapses, while at 2 to 3 years of age, the number of synapses per neuron increases up to 15,000, and the child learns new skills and explores the world.
The brain retains this synaptogenesis ability, which is why we can learn new skills, activities, languages, and much more even in old age. Apart from this learning, this neuroplasticity is also referred to as the Brain’s self-repair capacity. It involves changes in the interneuronal connections by changing the number and strength of synaptic connections. The other mechanism by which the Brain changes itself is by “axonal sprouting”. In this undamaged axon (nerve endings) grows and reconnects with the damaged or injured neurons. The axons also join with other undamaged axons forming new neural pathways. For example, in stroke, the brain tries to recover functional abilities by coordinating weak connections, synaptogenesis, and axonal sprouting.
Similarly, if one hemisphere of the brain is damaged, the intact one takes over some functions by reorganizing and forming connections between intact neurons. You might think that if neuroplasticity helps in stroke recovery that why doesn’t every patient recover? The recovery depends on age, the size of the area damaged, and notably, the therapies offered during rehabilitation.
Types of Neuroplasticity
There are two types of neuroplasticity often discussed:
- Structural Neuroplasticity
In this type, the Brain changes itself by changing its neural connections. Neurons are produced continuously and integrated into the Brain throughout life. Changes in the strength of neural connections and changes in grey matter proportion are examples of structural neuroplasticity.
- Functional Neuroplasticity
It describes the permanent synaptical changes by altering and adapting the functional properties of neurons. It can occur in response to previous activity for making a memory, which is activity-dependent plasticity. Functional neuroplasticity also occurs in response to injury or damage to neurons to compensate for pathological events to recover physiological or behavioral patterns. Studies have shown life experiences such as video gaming, juggling, or musical training are associated with functional neuroplasticity.
Benefits of Neuroplasticity
Neuroplasticity, or the brain’s ability to change itself, have a significant impact on our lives. For instance, the following are some of the benefits it has:
● It helps in recovering from traumatic events such as stroke or other injuries affecting the Brain.
● It helps in recovering the lost function or ability due to damage to any part of the Brain. For example, if an area of the Brain controlling one sense is damaged, the other brain part takes it over.
● It enhances the functions in other areas of the Brain if one function is lost (compensatory neuroplasticity).
● It plays a role in enhancing memory and learning ability.
● It plays a role in improving cognitive functioning.
Neuroplasticity can be manipulated in both diseased and healthy brains. Utilizing the Brain’s ability to change itself plays a vital role in rehabilitation therapies and improving quality of life. Various research studies are showing the positive role of neuroplasticity in managing certain disorders. It helps get through depression, anxiety, ADHD, OCD, autism, and pain other than the functions mentioned previously.