In recent decades, our understanding of bilingualism has changed a lot. At first it was thought that mastering two vocabularies were causing language disorders in children. However, it has been shown that it is false. In fact, bilinguals perform better in school activities that require a good deal of attention, short-term memory and inhibition of impulses, it is what is known in psychology as “executive control”.
It is believed that the advantage of “bilingualism” is not due only to learning a new language, but, above all, to the systematic use of both. But there are still many people who doubt this, so neuroscientists at Georgetown University Medical Center have decided to establish if indeed speaking two languages is so beneficial for the brain.
In the experiment it was measured the volume of gray matter of the monolinguals and bilinguals. So they found that, in fact, people who speak two languages have more gray matter in the frontal and parietal lobes, which are the areas of the brain involved in executive control.
What is the function of gray matter?
The gray matter is found mainly in the cerebral cortex, the most complex area of the nervous system. The cells that make up the gray matter does not contain myelin, so they can not quickly transmit nerve impulses. Their function is to process information and facilitate the reasoning. So it has been associated the amount of gray matter with intelligence and ability to solve problems.
But the most interesting is that the volume of gray matter that exists in the brain depends largely on the experiences that people are living throughout life. In fact, a study conducted at University College London found that taxi drivers have more gray matter in areas of the brain involved in spatial navigation, which is not surprising since for their profession are forced to use a lot more of these areas of the brain.
Why speaking two languages is so beneficial for the brain?
These neuroscientists have wondered if the increase in gray matter volume was due to speaking two languages or rely on some unique vocabulary learned. To find an answer, they are not limited to analyze the brains of bilingual and monolingual people, but also worked with people who dominated their mother tongue and also knew sign language.
In this way they discovered that only those who speak two languages have a greater volume of gray matter. These results suggest that changes in the brain are not simply due to the acquisition of a larger vocabulary, but depend on the effort made by our brain when we speak, since it is forced to disconnect a language to turn to the other, thus involving different areas brain.
In fact, a previous study conducted at the University of Kentucky showed that bilinguals are better at multitasking because they can connect and disconnect rapidly. They are also more flexible and can adapt more quickly to unexpected changes. What’s more, it is known that these skills are maintained into adulthood, so that learning a second language also protects the brain from dementia.
These studies reveal that our brain has an enormous plasticity and changes depending on the stimuli, even in adulthood. Therefore, if you do not know a second language you still have time to learn it and, above all, practice it.
Sources:
Olulade, O. A. et. Al. (2016) Neuroanatomical Evidence in Support of the Bilingual Advantage Theory. Cerebral Cortex; 26 (7): 3196-3204.
Gold, B. T. et. Al. (2013) Lifelong Bilingualism Maintains Neural Efficiency for Cognitive Control in Aging. The Journal of Neuroscience; 33(2): 387-396.
Fergur, I. M. et. Al. (2010) Delaying the onset of Alzheimer disease. Bilingualism as a form of cognitive reserve. Neurology; 75(19): 1726-1729.
Maguire, E. A. et. Al. (2006) London taxi drivers and bus drivers: a structural MRI and neuropsychological analysis. Hippocampus;16(12): 1091-1101.
