The Benefits Of Raising Bilingual Kids: The Critical Period Hypothesis
“Your brain may actually look and work differently than your monolingual friends”
The fact that language learning involves both types of functions of the brain: the one of the left hemisphere (analytical / logical functions) and the one of the right hemisphere (emotional / social functions) while lateralization develops gradually with age has lead to the critical period hypothesis.
According to this theory, children learn languages more easily because the plasticity of their developing brains lets them use both hemispheres in language acquisition, while in most adults language is lateralized to one hemisphere, usually the left. If this is true, learning a language in childhood may give you a more holistic grasp of its social and emotional contexts.
But regardless of when you acquired additional languages, being multilingual gives your brain remarkable advantages. Some of them are even visible, such as a higher density of the grey matter that contains most of your brain’s neurons and synapses. The workout a bilingual brain receives during its life can also help delay the onset of diseases such as alzheimer and dementia.
The idea of major cognitive benefits to bilingualism seem intuitive now, but it would have surprise earlier experts. Before 1960, bilingualism was considered a handicap, that slowed a child development by forcing them to expend too much energy distinguishing between languages. A view based on flawed studies. And while a more recent study did show that reaction time and errors increase for some bilingual students in cross language test, it also showed that the effort and attention needed to switch between languages triggered more activity in, and potentially strengthened, the dorsolateral prefrontal cortex. This is the part of the brain that plays a large role in executive function, problem solving, switching between tasks, and focusing while filtering out relevant information. So while bilingualism may not necessarily make you smarter, it does make your brain more healthy, complex and actively engaged.
