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The Bilingual Brain Book Summary – Albert Costa

What you will learn from reading The Bilingual Brain:

– How learning a language from a young age or later in life affects your brain.

– The advantages and disadvantages of learning a second language.

– The differences between monolingual and bilingual behaviour.

The Bilingual Brain Book Summary:

I’ve never been someone to enjoy language learning. I like the idea of it but I’ve never enjoyed the classroom experience.

Language has depth and meaning, but when you take it out of its environment, in this case social interactions it falls flat, nothing sticks and it becomes soulless. Just words on a page rather than any meaning behind it.

This book was a great introduction back into language. It’s not so much a language learning book but more of a book about how the brain develops when learning a language or being born in to a bilingual family.

Albert Costa does a great job of explaining the benefits and drawbacks of learning a second language while revealing hidden fundamentals into how to improve your language learning ability.

Bilingual Cradles

More than half the world’s population is bilingual.

There is a lot of depth to language, it’s not all about the words and sentences. Before the words come sounds, these are what we call phonological properties. When sounds are used correctly and in the right context it is known as the pragmatics of a language.

So, as a baby our first priority is to identify the sounds of a language before adding on words and meaning.

Babies learn to speak approximately after a year.

When reading we have the luxury of seeing spaces, these indicate the end of words and therefore the words themselves. However when we are babies, we can’t read and are therefore left to rely on our auditory senses. 

Think of it like listening to a song in a foreign language, you are more likely to hear 10 words as 1 as you can’t differentiate them.

So, with all this being said, babies build up a storage unit of all these different sounds and the rules that correspond them to each other, e.g. the word ‘straight’ is built up of the sounds str and aight, so they know that str followed by gla wouldn’t make any sense.

The rules that they use are called phonotactic rules, they are patterns of intonation and accentuation.

Some languages are tonal, this means that you can say the same word, but it has different meanings depending on the tone you say it in.

When a baby is exposed to two languages, it has to focus harder on the differences between the languages phonological properties, meaning they have a higher sensitivity to novel sounds. The difficulty of this increases if the two languages are of the same phonological family (e.g. French and Spanish).

Studies have shown that new-borns show a preference to the language that their mother uses when pregnant.

When a baby is presented with two languages, they are forced to try and gather as much information as possible, this includes visual cues as well as auditory information. This early conditioning means bilinguals are better at extracting information from people. 

Another area in which babies tend to break a language down is through the use of what we call phonemes. These are the smallest unites that differentiate two words, e.g. rat, bat, etc.

This means the sensitivity to phonemes in babies is very high, as a slight mistake could result in an entirely different word. 

As we grow older our ability to process phonological elements in a language that we grew up with gets stronger. However, because we don’t require being so sensitive to sounds anymore, our ability to learn a new language can be harder. 

When a baby pieces together the different sounds of a word, they can then start to relate it to an object, this in turn increases their word vocabulary as well as creating meaning behind it.

Interacting in a language attracts more of our attention than merely being exposed to it in a classroom. This means, engaging in social interactions is better for learning languages.

With all this being said, although a bilingual baby has a different approach to learning languages, both bilingual and monolingual babies learn at the same pace.


Two Languages, One Brain

Language belongs to one of our cognitive abilities. 

Studies have been done on bilingual people to measure the impact of brain damage on their languages (cognitive processes). It turns out that one language can be affected while the other stays intact. This means that both languages are cognitively independent to an extent and work on separate circuits. 

When learning a language, we tend to start with nouns and verbs because they’re more relatable in terms of how we see the world, this being through objects and actions. 

Just like the storing of sounds (sound lexicon), we store words and build them up over time (word lexicon). Some think that one of the reasons why we seek out nouns and verbs is because we store them in correspondence to either one. 

Anomia refers to a difficulty in retrieving words from our lexicon. It is the equivalent of ‘it’s on the tip of my tongue’ but more frequent.

Naturally learning a second language requires more neuronal resources for processing (brain power). 

Although a second language may require more resources, this does not mean that it takes priority over the first. The first language is practically unaffected by the second. 

Sometimes when we go to speak a new language, we find that the words don’t come out. This is due to our ability to retrieve words from our word lexicon. The more we retrieve the quicker we get. 

By learning a language, we have to learn its grammatical structures. Think of these as rules for the language. When we switch languages, we are switching rules as not every language has the same grammatical makeup. This is called code switching. 

The problem with having two languages in your head is that sometimes the more dominant one overpowers the other mixing the rules and therefore your ability to use the language correctly.

This is where linguistic control comes in. You see our brains can’t switch off languages in our heads, but it can do the next best thing and control the dominant one from interfering. Naturally, our linguistic control at the beginning stage of learning a second language is weak, but like any skill, the more you use it the better you get. 

A strange phenomenon with code-switching is that it requires more effort to switch back to our dominant language. Why? Well, think of it as a basic equation. When switching from our dominant to a second language, all we need to do is turn on our linguistic control, however, when switching from a second language to our dominant, we have to remove that control and then switch, thus taking more time.

Think of it like a bar graph that goes up and then has to go back down to increase the other one.

Think of linguistic control being a set amount. The more dominant a language is the more likely linguistic control will be used to control it, however, if both languages are of the same level then the linguistic control is shared equally among both, meaning the code-switching is much more fluid.

For a baby to learn a language they have to adapt, they start with the sounds, then the words and then the meaning. It is the perfect step process for easing into it. Unfortunately, when we grow up our ability to learn a new language is restricted by the fact, we already have one. Our adaptive skills aren’t as strong as those of a baby and so we have the obstacle of our own language that we have to overcome. Naturally, this requires more mental effort than if we were babies.


How Does Bilingualism Sculpt the Brain?

The speed and accuracy of retrieving words depend on the familiarity of them. The more familiar the word (e.g. table) the easier it is to retrieve. The less familiar the word (e.g. cavern) the harder it will be.

Because bilingual people have more words in their lexicon, this means more choice and less familiarity, thus making them slower and less reliable at word retrieval. 

Over time our speed and accuracy of word retrieval slows down.

Words that do not resemble words in another language are called non-cognate words. These words are harder to retrieve than resembling ones.

Our vocabulary is determined by the contexts in which we speak. E.g. if we are constantly in a football environment, words related to football will be more familiar and easier to retrieve from our lexicon.

Obviously not all languages are completely different, naturally there are some rules that cross over, these help us learn a new language much faster.

the similarity between languages can help to transfer certain properties from those we know to new ones.

In addition to the crossover of rules, bilinguals also find the act of speaking another language easier. This is because they have already acquired linguistic control through their second language, whereas monolinguals have to start from the beginning.

When describing things, we normally fall victim to assuming that other people have the same knowledge as us and that they will understand everything we say when in reality this is not so true. This concept has many names, the curse of knowledge, egocentric bias, and many more. 

Studies have shown that bilinguals who have been brought up in multilingual households have to adapt to what each parent is saying. This forces them to consider something from both their perspectives and thus reduces their egocentric bias. 

As we now know, speaking a second language requires a lot more effort than if we were speaking our dominant one. This means that bilinguals overexert during speech production. 

We should remember that there is a difference between learning a language growing up and actively learning a language later in life. The former is more adaptive whereas the latter is more controlled but less efficient.


Mental Gymnastics

Language is part of what we call the executive control system. It is one of its many capabilities along with driving, attention, multitasking etc. So, if bilingualism is training language and language is training our executive control systems, then bilingualism can affect our control systems. 

A way in which it affects it is by improving our attention and focusing skills. This is especially prevalent in conflict resolution as it requires a lot of attention.

The main point behind this is that continued use of a second language has an effect on the attentional system whether linguist or non-linguistic. This meaning it activates a more distributed brain network.

“Ageing is accompanied by cognitive decline that negatively affects many basic cognitive processes, such as attention, language, memory, and so on.”

The reason why this is relevant is that by improving these cognitive processes throughout life, we create what is called a cognitive reserve. This is what it says on the tin, it is a reserve of cognition that we use when our cognition levels fall to a certain point because of neurodegenerative diseases such as Alzheimer’s or Dementia. 

Language being one of the many cognitive processes means that by learning a new one, we are working our cognitive muscle. This helps us increase our cognitive reserve if our future self requires it.

However, just a word of warning, cognitive reserve can only last so long and in the words of Albert Costa, “the degeneration is so great that cognitive reserve can no longer help.”

When we compare cognitive reserve in respect to monolinguals and bilinguals, monolinguals don’t have as much, however, the symptoms of degeneration is gradual. Bilinguals on the other hand have more cognitive reserve but when it runs out the symptoms are sudden.


Making Decisions

It’s no surprise that learning a language in a social context is more effective than merely being taught in a classroom. Learning a language so methodically like in a classroom can limit us to the literal meanings of the words, whereas applying it to social contexts enriches it them emotion and allows them to be fluid and transferable.

Language Pragmatics is the effect of context or situation on the interpretation of words. This is especially important as many words can be used in many contexts as the meanings of words depend on what is being intended. So then, the idea is to acquire a good knowledge of when and when not to use them. 

Albert Costa talks about humour being a perfect example of one of these contexts and how it plays out: “Humour is an extremely complex communicative act in which many different tricks come into play. We can make jokes that involve irony, indirect language, surprise, tone of voice, double meaning of words, phonological similarity, and so on. But above all, humour often requires one to forget literal meaning and realise that what is being said isn’t necessarily what should be interpreted,”

A great way to improve learning a language in different contexts is to listen to music, watch video in that foreign language, play online games, etc. Anything that is social cannot be predicted by a textbook and is therefore a lot more realistic in terms of how people speak.

It turns out that our attentional abilities can be hijacked by emotion. Emotion changes the direction of where we are focusing and puts it on the thing that is eliciting our emotions. This means that emotional stimulating words can distract us from the concept we are focusing on and instead lead us to make less rational decisions.

Studies have shown that when we actively learn a language later in life we don’t have the same depth to it as we do with our dominant language from social interactions. This means that we are more literal in our approach and therefore less sensitive to emotional stimuli in a foreign language.

What does this mean exactly? Well, because we aren’t overpowered so much by emotional stimuli, we are less likely to act impulsively and therefore think more rationally.

This leads to a concept called ‘loss aversion.’ This where the loss of something has a greater emotional tax than winning something of the same magnitude. E.g. It feels worse to lose £10 than the feeling of winning £10. The reason why this is relevant is because loss aversion is triggered by our emotional reactions. Thus, we are less likely to feel loss aversion when confronted by a scenario in a second language.

The same goes for ‘risk aversion’ which refers the notion that human beings tend to prefer safe options over others that are more risky, despite the fact that the safer ones are not necessarily those that can benefit us more.

Albert costa puts it very well: “Facing problems in a foreign language leads to better decisions. When the problem involves some difficulty from a linguistic point of view, we put on our thinking caps and rethink our decisions, which allows us to block intuitive responses (System 1) and to make us think twice about the options presented (System 2).”

Although we are better at tackling emotional system problems in a foreign language, there is no evidence to suggest that this is the same with tackling logical problems.

Interestingly language and accent play a huge part in trust and relationships. It is a fact that we are social creatures and therefore go out of our way to be part of a group, tribe, etc. The groups we choose normally have something in common with us, one of these things is language and accents. 

Studies have shown that we prioritise communication over skin colour, and therefore, someone with a dissimilar language or accent is deemed more different than that of someone with a different skin colour.

Funnily enough, we are more likely to trust what someone says if they speak the same language or have the same accent even if what they are saying is false.