The Triple Helix @ UChicago

Winter 2016

"The Bilingual Mind" by Lindsey Jay

 

Always boasting to your friends how you can speak three different languages? Now you will have yet another thing to brag about. Being bilingual or multilingual is not only practical but is also beneficial for a multi-tasking brain. Research has revealed that possessing a bilingual mind may overall have greater cognitive benefits than having a monolingual mind. 

Previously, researchers believed that bilingual children would perform lower on cognitive tasks, such as symbol manipulation and reorganization, than monolingual children [1]. They reasoned that having to switch between multiple languages would be confusing and would cause unwanted interference for children when trying to change thoughts between languages [1]. However, Professors Peal and Lambert, who studied French-speaking monolingual children and French-English-speaking bilinguals in Canada, found that bilingual children performed higher not only in non-verbal spatial tasks, such as symbol manipulation and reorganization, but also language tasks overall [1]. They had better performance multitasking in complex symbol (not correlating to any language) manipulation and language manipulation. Later studies found that bilingual children had a significant advantage in metalinguistic awareness (such as differentiating between the form and meaning of words) and non-verbal problems that required participants to ignore misleading information [1]. 

Nonetheless, bilinguals must deal with a problem that monolinguals do not face: switching between languages. This switching between languages is seen in in electroencephalography (EEG) scans of bilinguals, where joint activation of the languages was observed [1]. Researchers Thierry and Wu used EEG to study how the brain keeps both Chinese and English online. They found that in Chinese speakers studying English words, participants accessed the Chinese forms of words when making semantic judgments about the English words [1]. Their results showed that both brain regions are activated no matter what language is being spoken, and a person does not think discreetly in just one language at a time [1]. This finding brought up the idea that bilinguals must learn how to switch their attention between the two languages. Because they must constantly shift their attention, they may overall have better executive control. Executive control is the set of cognitive skills based on limited cognitive resource for functions such as inhibition, switching attention, and working memory [1]. Though bilinguals were found to have relatively weaker skills in their respective languages compared to monolinguals, they demonstrated better executive control than their monolingual counterparts [1]. 

Further research has shown that in fMRI scans language switching is accompanied by activation in the dorsolateral prefrontal cortex (DLPFC), which is part of general executive control system [1]. Learning another language actually broadens and strengthens connections within one’s neural network. This leads to advantages on particularly difficult tasks that demand switching thought processes in the same way that using multiple languages requires [1]. More broadly speaking, bilinguals seem to have a greater ability to monitor their environment than monolinguals [2]. Bilingual minds have “exercised” this metaphorical muscle of monitoring environments much more than monolingual minds, and have the stronger neural networks to show for it. 

The benefits of bilingualism also extend into aging minds. In a study of 44 elderly Spanish-English bilinguals, Professor Tamar Gollan of University of California, San Diego found that they were more resistant than monolinguals to the onset of dementia and other Alzheimer symptoms [2]. Bilingualism may contribute to cognitive reserve in old age, which is the idea that engagement in stimulating physical or mental activities can help maintain cognitive functioning in healthy aging and help delay the onset of dementia [1]. Thus, a more active brain may be the cause of delayed symptoms of dementia and Alzheimer’s in aging individuals. 

These findings have been focused on people who have been bilingual since early childhood, but what about learning a new language later in life? It turns out that your brain will still reap benefits, but different ones from those discussed earlier. The hippocampus, left middle frontal gyrus, inferior frontal gyrus, and superior temporal gyrus, which deal directly with language learning, all showed an increase in brain size according to Martensson et al. from Lund University [3]. It is unclear as to whether learning a new language later in life could help monolinguals to the same degree that it helps bilinguals from early childhood. But because the brain has been shown to form new connections in the brain regions associated with language learning, it is possible that if both languages are used regularly enough it could lead to increased executive control. The brain is highly plastic, and the possibility that learning another language later in life has similar cognitive benefits should not be discounted. 

Another question that scientists have yet to address is exactly how bilingual a person must be in order to benefit. According to Professor Giannakidou at the University of Chicago, bilingualism lies on a spectrum rather than on a binary [4]. It is thus difficult to even define what exactly “bilingualism” is in the first place. Moreover, it is unclear whether learning multiple languages would have an additive effect on the cognitive benefits. Overall, the next step this research takes should address these questions to help resolve these more nuanced issues.

References

[1] Bialystok, Ellen, Fergus I.m. Craik, and Gigi Luk. "Bilingualism: Consequences for Mind and Brain." Trends in Cognitive Sciences 16, no. 4 (April 2012): 240-50. doi:10.1016/j.tics.2012.03.001. 
[2] Bhattacharjee, Yudhijit. "Why Bilinguals Are Smarter." The New York Times. March 17, 2012. Accessed April 26, 2016. http://www.nytimes.com/2012/03/18/opinion/sunday/the-benefits-of-bilingualism.html. 
[3] Johan Martensson, et al. "Growth of Language-related Brain Areas after Foreign Language Learning." Growth of Language-related Brain Areas after Foreign Language Learning. October 12, 2012. Accessed April 26, 2016. doi:10.1016/j.neuroimage.2012.06.043. 
[4] Giannakidou, Anastasia. "Dimensions of Bilingualism." Lecture, Language and the Human, Kent 107, Chicago, November 18, 2014.

 
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