By Angela Grant
Does using two languages affect the brain?
The short answer here is yes, and in a good way. Over the past few years, there has been an explosion in research examining the brains of bilinguals, and many studies have found benefits of bilingualism in multiple areas of the brain (Li, Legault & Litcofsky, 2014). Perhaps unsurprisingly, figuring out why that is and how it works is very complicated. In this article, we’ll be discussing an approach to studying and understanding bilingual brains that distinguishes between language comprehension on the one hand, and language production on the other. If you’ve ever taken a foreign language class, you may have noticed that it was easier to understand your teacher than it was to ask a question, or to try having a discussion in the language you were learning. This is because the demands on the brain are different when we listen to someone else speaking compared to when we ourselves speak. Researchers are now finding that practicing listening in your second language and practicing speaking in that language affect different areas of the brain.Does using two languages affect the brain?
How do listening and speaking affect the brain differently?
A new study by Blanco-Elorrieta and Pylkkänen (2016) recorded brain activity while adult bilinguals either listened to or produced speech in each of their languages. They found that the areas of the brain that were active during comprehension and production were different: Comprehension relied on structures near the center of the brain, while production used those closer to the front.
Another study by Kuhl and colleagues (2016) also examined comprehension and production. They measured white matter—the structural brain tissue that connects different areas of the brain—in bilingual adults. They asked these bilinguals to report how much they spoke or listened to their second language, and found that experience listening and speaking the second language were each associated with changes in areas of the brain that were remarkably close to those observed by Blanco-Elorrieta and Pylkkänen (2016). Excitingly, they found that bilinguals who spent more time practicing each skill tended to have healthier white matter in each of those areas. Taken together, these studies show that exercising the brain by both listening and speaking in two languages has positive and unique effects on brain structure.
What can families learn from this?
The take away message from these studies is that both listening and speaking two languages have concrete positive effects on the brain. Bilingual parents in the U.S. often feel that they should speak English to their child, or become concerned if they speak the home language and the child responds in English. But research shows that there are good reasons to continue speaking to your child in the home language, regardless of how they respond. Just listening to you provides stimulation that leads to brain growth. And if you can encourage them to speak as well, it’s all the better!
References
Blanco-Elorrieta, X. E., & Pylkkänen, L. (2016). Bilingual Language Control in Perception versus Action:MEG Reveals Comprehension Control Mechanisms in Anterior Cingulate Cortex and Domain-General Control of Production in Dorsolateral Prefrontal Cortex. The Journal of Neuroscience, 36(2), 290–301. http://doi.org/10.1523/JNEUROSCI.2597-15.2016
Kuhl, P. K., Stevenson, J., Corrigan, N. M., van den Bosch, J. J. F., Can, D. D., & Richards, T. (2016). Neuroimaging of the bilingual brain: Structural brain correlates of listening and speaking in a second language. Brain and Language, 162, 1–9. http://doi.org/10.1016/j.bandl.2016. 07.004
Li, P., Legault, J., & Litcofsky, K. A. (2014). Neuroplasticity as a function of second language learning: Anatomical changes in the human brain. Cortex, 58, 301–324. http://doi.org/10.1016/j.cortex.2014.05.001
Grant is a PhD candidate in cognitive psychology. Write to her with questions and comments at amc497@psu.edu. |