Based on these previous findings, the team concluded that when the brain learns a new skill it initially increases in volume, but then after a process of elimination retains only the most useful brain cells, eliminating those not more effective, and thus eventually returning to its pre-learning size.
“Brain matter volume increases in the initial stages of learning and then renormalizes [sic] partially or completely,” said Wenger in a recent statement. “This seems to be an effective way for the brain to first explore the possibilities, call in different structures and cell types, select the best ones, and get rid of the ones that are no longer needed.”
The research adds further understanding to the neuroscience concept of plasticity. Brain plasticity refers to how the brain acquires new information by constantly reorganizing its neurons in order to function differently. As reported in the study, the concept was first put forward in 1894 by Nobel Prize winner Santiago Ramon y Cajal, who proposed that the brain undergoes physical changes in structure during learning. Now, over 100 years later, we understand the concept slightly better.
During plasticity, the brain reorganizes and assigns neurons new and different functions in order either to acquire a new skill or to overcome injury, such as a stroke or trauma, that may have caused serious neurological damage. Often, other parts of the brain will take over, learning the role of the lost brain cells as a way to compensate. For example, if the area of the brain associated with speech is destroyed, the brain may use plasticity to cause other areas of the brain not originally associated with this speech to learn the skill as a way to make up for lost cells.