When it comes to bilingualism and its effects on the brain, there is clear evidence that suggests that knowing and communicating in more than one language has positive cognitive benefits.
This isn't something that is limited to children and adolescents even adults can learn a second language, commit to it and see the actual cognitive benefits of being bilingual.
Some hypotheses and early research also suggest that mental diseases like Dementia and Alzheimers can be delayed or even prevented if a person is bilingual. In this post, we will discuss the effects of bilingualism on the human brain and how it can be beneficial as a child and as an adult.
How does being bilingual, benefits the brain?
Executive functions are the most complex of brain functions, the ones that make us human and far more evolved than apes and other animals. The brain carries out these functions in the newest brain regions from an evolutionary standpoint. The 3 major areas here are the prefrontal cortex, the supramarginal gyri, and the anterior cingulate. The names aren't important, but their functions are. These 3 are responsible for advanced processing and helping us link words to their meanings. This means they are directly responsible for our cognitive abilities.
Brain scans of individuals who are bilingual or speak multiple languages found that they possess a greater density of grey matter. This density was most pronounced in people who were highly proficient in two languages and learned both languages before the age of 5. This was a clear advantage over monolingual children or peers who had an average density of grey matter. Grey matter refers to the volume of cells and dendrites in a brain. Bigger the grey matter, the higher the number of brain cells, and the higher the number of dendrites leading to faster brain synapses ultimately a sign of greater cognitive control.
Bilingualism also promotes the integrity of white matter as a person ages. White matter is the fatty substance that covers axons which are the main projections in neurons that help build a neuron network. White matter allows messages to travel faster through the brain. If you have more neurons in your brain, you have a physical advantage to facilitate optimal communication.
The best part is that these benefits aren't limited to language learning but also apply to other parts of life, where your brain can cope better with distractions. Since a bilingual person is constantly switching languages, they are aware of what they should say and where, and they exercise their brain more, leading to this enhanced cognitive control.
Cognitive benefits for bilingual children
Bilingualism was earlier believed to confuse children and in some cases cause mental retardation as well. This was nothing but a consensus of a poorly conducted study where the subjects included bilingual children from war-torn countries who were orphans, refugees, or worse been to concentration camps. While they probably suffered from PTSD, their confusion was attributed to their bilingualism.
It was in the 60s when a study published at McGill University in Montreal showed that bilingual children don't have any cognitive decline or mental retardation but rather have heightened cognitive benefits.
Bilingual children show advantages in their metalinguistic awareness. This is what enables a human being to understand that language goes beyond its literal meaning, and this meaning can change based on tonality, the environment, and wordplays like sarcasm and idioms.
Children who speak a second language have been shown to have a superior ability to focus on one thing and immediately shift focus to another if and when required. Bilingual children are more prone to exercise their brains as they have to constantly switch languages based on contextual and environmental cues. This leads to a stronger cognitive response because they are constantly amplifying one language and suppressing the other.
They also have better-developed command centers in their brains which make them more suitable to solve tasks that require planning and problem-solving. This means they are far better at categorizing or sequentially arranging something. This can be anywhere from getting ready for school to driving a car. A bilingual brain is more likely to find order in chaos.
Bilingualism has also great practical advantages for adults. Young adults who know more than one language have outperformed their monolingual peers in tasks related to concentration and attention. This again is attributed to the need of switching between two languages and how that exercises the brain and builds a stronger neural network.
Some preliminary research also suggests that bilingualism can delay the onset of Alzheimer's by 4 years in an adult. Although the studies around this are not very conclusive at this time.
Is it better to learn a language as a child than as an adult?
For the longest time, it was believed that in order to be truly bilingual, you need to start early. This is what will ultimately lead to strong language skills in the native language and the second language. But we know that people learn to speak languages later on in life and do quite well at it.
This depends on two factors, the plasticity of the brain and the quality of input of the target language. As we age, our brains become more rigid which means the plasticity of the brain is lower whereas as children, the level of neuroplasticity is higher. It is also believed that an adult sitting on Duolingo at 10 PM in the night after an 8-hour shift will have a lower level of language input than that of a child who grew up with one parent-one language learning technique or even a whole family speaking a foreign language.
It is likely a combination of both these things and also individual mindset and motivations. Some people succumb to challenges, others thrive in them.
Does a bilingual brain age differently from that of a monolingual brain?
Short answer, yes they do. Learning languages can really tackle cognitive decline with age. But how?
Well, with the research that is currently available to us, we can deduce that cognitive decline begins at the age of 25 and slowly worsens with age. Every passing year makes it worse. While this manifests in physical forms in both bilingual and monolingual brains, people who speak two languages or more, compensate for this decline by using different neural pathways once the original ones have deteriorated.
What this means is that the initial growth in grey and white matter leads to a richer network of nerve endings and neurons, which is a sign of healthy grey and white matter. This richer network is more robust, and in-turn prolongs deterioration. Researchers call this theory cognitive compensation and that is exactly what is happening here.
What does this mean for parents raising bilingual children?
We just read about the advantages of a bilingual brain and it's truly awesome. Speaking multiple languages has a stark and impressionable effect on the brain at any age.
The first piece of advice is to always have good quality and quantity of input towards learning a second language. In addition to this, you need to use the second language thoroughly for day-to-day interactions with the first language, so the child can see the importance of the second language and make an active effort to learn it. You should also look for constant vocabulary enrichment opportunities in the two languages.
Another concern for parents is the mixing of two languages at once. This is pretty normal behavior and over time your children will learn the difference by the age of 4 and ultimately grow into truly bilingual adults.
Simply concentrate on raising your children to be bilingual, the cognitive benefits will show over time. This does not mean that you push them to be a polyglot immediately, once they are fairly fluent in two, you can introduce a third or fourth language.
We can conclude that bilingualism has some clear advantages for the brain both in physical and practical use cases. Knowing more than one language is truly a superpower that greatly affects our abilities to learn and understand better. These benefits can be observed both in children and in adults, where its shown to slow down cognitive decline and in some cases, delay the onset of Alzheimer's. While a child's brain is better at learning languages, adults can successfully learn a new language with the right mindset and input. Parents must try to raise their children to be bilingual and enrich their quality and quantity of input in the target language, be patient and educate themselves on the advantages and myths surrounding bilingualism.