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¿Hablas español? Parlez-vous français? 你会说中文吗？
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If you answered, “sí,” “oui,” or “会” and you’re watching this
in English,
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chances are you belong to the world’s bilingual
and multilingual majority.
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And besides having an easier time traveling
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or watching movies without subtitles,
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knowing two or more languages means that your brain
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may actually look and work differently than those of your
monolingual friends.
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So what does it really mean to know a
language?
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Language ability is typically measured in two
active parts, speaking and writing,
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and two passive parts, listening and
reading.
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While a balanced bilingual has near equal
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abilities across the board in two languages,
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most bilinguals around the world know and use
their languages
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in varying proportions.
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And depending on their situation and how they acquired each
language,
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they can be classified into three general
types.
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For example, let’s take Gabriella,
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whose family immigrates to the US from Peru when she’s
two-years old.
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As a compound bilingual,
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Gabriella develops two linguistic codes
simultaneously,
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with a single set of
concepts,
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learning both English and Spanish
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as she begins to process the world around her.
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Her teenage brother, on the other hand, might be
a coordinate bilingual,
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working with two sets of
concepts,
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learning English in school,
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while continuing to speak Spanish at home and with
friends.
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Finally, Gabriella’s parents are likely to be
subordinate bilinguals
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who learn a secondary
language
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by filtering it through their primary
language.
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Because all types of bilingual people can become
fully proficient in a language
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regardless of accent or pronunciation,
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the difference may not be apparent to a casual observer.
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But recent advances in brain imaging technology
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have given neurolinguists a glimpse
2:00
into how specific aspects of language learning affect the
bilingual brain.
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It’s well known that the brain’s left hemisphere
is more dominant
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and analytical in logical
processes,
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while the right hemisphere is more active in
emotional and social ones,
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though this is a matter of degree, not an
absolute split.
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The fact that language involves both types of
functions
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while lateralization develops gradually with
age,
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has lead to the critical period
hypothesis.
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According to this theory,
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children learn languages more easily
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because the plasticity of their developing
brains
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lets them use both hemispheres in language
acquisition,
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while in most adults, language is lateralized to
one hemisphere,
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usually the left.
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If this is true, learning a language in
childhood
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may give you a more holistic grasp of its social and
emotional contexts.
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Conversely, recent research
showed
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that people who learned a second language in
adulthood
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exhibit less emotional bias and a more rational
approach
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when confronting problems in the second
language
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than in their native one.
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But regardless of when you acquire additional languages,
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being multilingual gives your brain some remarkable
advantages.
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Some of these are even visible,
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such as higher density of the grey matter
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that contains most of your brain’s neurons and synapses,
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and more activity in certain regions when engaging a second
language.
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The heightened workout a bilingual brain receives throughout
its life
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can also help delay the onset of diseases, like Alzheimer’s
and dementia
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by as much as five years.
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The idea of major cognitive benefits to bilingualism
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may seem intuitive now,
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but it would have surprised earlier experts.
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Before the 1960s, bilingualism was considered a handicap
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that slowed a child’s development
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by forcing them to spend too much energy distinguishing
between languages,
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a view based largely on flawed studies.
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And while a more recent study did show
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that reaction times and errors increase for some
bilingual students
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in cross-language tests,
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it also showed that the effort and attention
needed
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to switch between languages triggered more
activity in,
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and potentially strengthened, the dorsolateral
prefrontal cortex.
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This is the part of the brain that plays a large
role
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in executive function, problem solving,
switching between tasks,
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and focusing while filtering out irrelevant
information.
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So, while bilingualism may not necessarily make you
smarter,
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it does make your brain more healthy, complex and
actively engaged,
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and even if you didn’t have the good
fortune
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of learning a second language as a child,
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it’s never too late to do yourself a favor
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and make the linguistic leap from, “Hello,”
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to, “Hola,” “Bonjour” or “你好’s”
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because when it comes to our brains a little
exercise can go a long way.
