Neuroplasticity in Early Bilingualism and in Blind Children

 

          Neuroplasticity is the incredible ability of the brain to modify and rewire itself in response to certain experiences. The brain will undergo structural and functional change throughout one’s lifespan. Evidence suggests that the extent to which neuroplasticity occurs depends on the age at which learning begins. Neuroplasticity is a hot topic in neuroscience research, but studying it can be challenging. Two methods have been proven as useful for studying the brain’s neuroplastic ability, and those are the study of bilinguals and the study of the blind.

            In the article, “Early bilingualism, language attainment, and brain development,” Dr. Berken et. al. investigates the differences in brain structure between individuals who have been bilingual from a young age and those who learned a second language later in life. Using PET and fMRI data, they found that brain structure and function is more effectively organized when two languages are learned simultaneously at a young age, and that second languages developed later in life have a smaller neuroplastic change. This affirms how age and neuroplasticity are related, more specifically, how within the first few years of life when the brain is still actively developing, new experiences have the largest capacity to affect and change neural structure and function.  

            These findings parallel those by Dr. Ortiz-Teran et. al in the article, “Brain circuit–gene expression relationships and neuroplasticity of multisensory cortices in blind children.” Sensory deprivation is known to induce neuroplasticity in the brain by reorganizing neural circuits. This is notably evident in blind individuals, who show functional connectivity reorganization due to their lack of sight. Using neuroimaging techniques and systems-level analyses, the researchers were able to find that the neural reorganization in blind children involves multisensory integration regions. Using within-group analysis, it was also found that functional connectivity changes also increased with age. Evidence was also found that the spatial cortical expression of genes underlies the reorganizational abilities of the multimodal cortex. These results are similar to those in the bilingual study as blind children show neuroplastic changes that continue as they age, similar to individuals who learn a second language from a young age. Neuroplastic changes are shown in both studies to be the largest in those at a younger age; however, in the study of blind children we see how the neuroplastic changes continue as the blind children age.

            The study of neuroplasticity offers insight into the way our brain grows and changes in response to new knowledge and experiences, and also provides helpful insight into understanding neuroplastic changes in those with sensory deprivation, which may one day help in developing therapeutical treatments to help those patients.

 

Sources:

Berken, Jonathan A., et al. “Early Bilingualism, Language Attainment, and Brain Development.” Neuropsychologia, vol. 98, 2017, pp. 220–227., https://doi.org/10.1016/j.neuropsychologia.2016.08.031.

Ortiz-Terán, Laura, et al. “Brain Circuit–Gene Expression Relationships and Neuroplasticity of Multisensory Cortices in Blind Children.” Proceedings of the National Academy of Sciences, vol. 114, no. 26, 2017, pp. 6830–6835., https://doi.org/10.1073/pnas.1619121114.