Learning a new language can be an extremely long process in order to become fluent – even if you are a native speaker. From the day we were born we are on a mission to speak, the curiosity of language to a child is clear to see as they strenuously try to communicate with us via babbles and gurgles. It’s a fascinating memory when a child says their first word, but even more fascinating when they can speak two languages. Some people accomplish learning languages two or three times over making them bilingual, trilingual or more. In fact it’s incredible the way any brain can function between two languages – so how is it actually done?
Scientists are only beginning to look closer at the mind of a polyglot in order to understand learning influences, behaviour and the brain structure itself when a second, third or fourth language is acquired.
Humans have been known to be simple linguists even inside the womb, before birth. This is because brain mechanisms are fully developed from 30 weeks onwards and therefore are able to hear what their mothers say and absorb elements of the language. Elisabeth Cros, a speech therapist with the Ecole Internationale de New York states that “Before 9 months of age, a baby produces a babble made up of hundreds of phonemes from hundreds of languages.” 
Learning two languages whilst a child is young is generally easier as they aren’t fully aware of what they are doing. But how do we choose which language to speak in, with more than one language to choose how does our brain function and not constantly mix between languages? The truth behind this is that the brain, regardless of age, does in fact get confused when juggling more than one language. Ellen Bialystok of Toronto’s York University calls it the dog-chien dilemma.  This is when a person who speaks two or more languages toggles between two words in order to describe something.
However there have been numerous studies which identity the benefits of knowing more than one language within education, work and even health. For example studies conducted on both monolinguals and bilinguals showed different results when it came to cognitive decisions. Even though both groups performed tasks accurately it was clear to see that bilinguals performed faster as well as more metabolically economical in executing the cognitive mission, using less energy in the frontal cortex than the monolinguals.
The brain is the most complex organ of our bodies with its function to control the other organs of the body, a vital organ that without it we would cease to exist. As previous studies have proved knowing a second language keeps the brain sharper later on in life.  Preliminary imaging work suggests that language behaviour can be visible in the brain. Some studies, for example, have shown a thickening of the cortex in two brain regions but most importantly the left inferior parietal. This part of the brain helps code language and gesturing.
Bialystok has also found differences for bilinguals which suggests denser signalling and complexity of functions due to fatty sheathing that insulates nerves and improves ability to communicate – this may account for the decision making when choosing between which language to use during communication.
Do you face any challenges in communication because you speak more than one language?