Speaking more than one language has clear advantages but mixing them all is not unusual. Researchers are studying the impact of speaking two or more languages on people’s brains.
1. Bilingual and multilingual people
A team of neuroscientists has discovered that the brain uses a shared mechanism for combining words from a single language and for combining words from two different languages. Its findings indicate that language switching is natural for those who are bilingual because the brain has a mechanism that does not detect that the language has switched, allowing for a seamless transition in comprehending more than one language at once.
From research we know that as a bilingual or multilingual, whenever you’re speaking, both languages or all the languages that you know are activated. For example, when you want to say ‘dog’ as a French-English bilingual, not just ‘dog’ is activated, but also its translation equivalent, so ‘chien’ is also activated.
Mathieu Declerck, Senior Research Fellow at the Vrije Universiteit in Brussels
Sarah Phillips, a New York University doctoral candidate explained how our brains are capable of engaging in multiple languages. “Languages may differ in what sounds they use and how they organize words to form sentences. However, all languages involve the process of combining words to express complex thoughts,” said Phillips.
Tamar Gollan, a professor of psychiatry at the University of California San Diego has been studying language control in bilinguals for years. Her research has often led to counterintuitive findings: “I think maybe one of the most unique things that we’ve seen in bilinguals when they’re mixing languages is that sometimes, it seems like they inhibit the dominant language so much that they actually are slower to speak in certain contexts,” said Gollan.
2. Reverse dominance
When adults are immersed in a new language, they can find it harder to access the words from their native language, a process called reversed dominance. Its effects can be particularly evident when bilinguals switch between languages in a single conversation, said Gollan. The professor explained that when mixing languages, multilinguals are navigating a sort of balancing act, inhibiting the stronger language to even things out – and sometimes, they go too far in the wrong direction.
Bilinguals try to make both languages about equally accessible, by inhibiting the dominant language to make mixing back and forth easier. But they sometimes ‘overshoot’ that inhibition, and it ends up coming out slower than the non-dominant language.
Tamar Gollan, Professor of Psychiatry at the University of California San Diego
Gollan’s experiments also found reversed dominance in another surprising area – pronunciation. Participants sometimes read out a word in the right language, but with the wrong accent.
“Sometimes bilinguals will produce the right word, but with the wrong accent, which is a really interesting dissociation that tells you language control is being applied at different levels of processing,” she explained. “And there’s a separation between specification of accent, and specification of which lexicon you’re going to be drawing the words from.”
3. Language interference
Most multilingual people are quite capable of keeping their native language’s grammar straight. However, Kristina Kasparian, a writer, translator and consultant who studied neurolinguistics at McGill University in Montreal, Canada, said when people are immersed in a second language, it does impact the way they perceive and process their native language.
Kasparian’s study testing Italian students through an electroencephalography (EEG) method show that our languages aren’t just static throughout our lives but shifting, actively competing and interfering with each other.
Researchers believe that a bilingual brain can compensate for brain deterioration by using alternative brain networks and connections when original pathways have been destroyed. They call this theory “cognitive compensation” and conclude that it occurs because bilingualism promotes the health of both gray and white matter.
