The brain is both irreplaceable and one of the most complex and fascinating organs in the human body. The brain consists of approximately 100 billion nerve cells, which create around 100,000 billion synapses, the connections between the nerve cells (Gorelick & Sorond, 2024; Tran, 2022). The more synapses in the brain, the easier it is to adapt to new challenges. In order for the brain to create more synapses, it is necessary to learn new things (Nordengen, 2020). Brain development is often described as consisting of three stages throughout the life course. These stages are neuroplasticity, pruning and neuronal loss, which collectively express the lifelong adaptation of the brain (Patel et al., 2018).
Neuroplasticity involves the brain forming new neural connections and strengthening synapses between neurons throughout a person’s life (Cherry, 2024). The brain has an innate ability to adapt by altering the connections between nerves and brain cells based on behaviour, environment and experiences. Pruning is the process by which the brain removes neurons and synapses that it does not need. This occurs mainly during the age range 2-10 years (Rowden, 2023). Neuronal loss concerns the loss of nerve cells during adulthood (University of Barcelona, 2024). The loss of nerve cells will affect brain function and health.
Although it was previously believed that these three stages followed each other without any overlap, it is now known that the brain can continue to develop and adapt, even as it ages. Because of neuroplasticity, brain health can therefore be promoted throughout life by reducing risk factors and strengthening protective factors (World Health Organization, 2022).