Tuesday, May 12, 2015

Is Multilingualism a Form of Cognitive Enhancement?

The following post is part of a special series emerging from Contemporary Issues in Neuroethics, a graduate-level course out of Emory University’s Center for Ethics.

People often ask me what language I dream in. I usually tell them that I dream in both languages – Romanian and English – and that it depends on the content of the dream and on the people featured in it. I associate emotional states with my native Romanian, while organized, sequential thinking is easier in English. Most of the time, I am not even aware of the identity of the language I produce and hear in my dreams.

Leaving the mysterious dimension of dreams behind, how does the multilingual brain navigate the world? Faced with an information-dense environment, it is able to switch its language of appraisal at the moment’s need. Consider the increasingly large group of bilingual English-speaking Hispanics in the United States. Most of them use English in their academic and work environments, then effortlessly switch to Spanish when talking to family members and other Spanish speakers. They also retrieve autobiographical memories in the original language of encoding without losing any more details than a monolingual individual. Given a context, multilingual individuals are able to adjust to the linguistic requirements of the situation. The multilingual brain is, therefore, an adaptable brain.

This leads us to the next point of inquiry. How does speaking several languages sculpt the brain? The Brain and Language Laboratory for Neuroimaging led by Dr. Laura-Ann Petitto has been investigating the differential activity in monolingual and bilingual brains during comprehension tasks, and has found that bilinguals show increased activation in the left inferior frontal cortex, an area associated with semantic processing and behavior inhibition. Another group led by Dr. Jubin Abutalebi has found that the brain of bilinguals recruits more areas when processing language than the brain of monolinguals. Finally, a recent study replicated the finding that learning a second language early in life changes the structure of white matter in the brain. This study is of particular interest, because it suggests that learning a second language later in life and using it concurrently with the first has the same effects on the brain.
Image result for ny times manzana
Image by Harriet Russell. From www.nytimes.com
So what are the behavioral manifestations of these properties of the multilingual brain? Research shows that there are many. First, multilingual individuals show better cognitive abilities. They easily block out distractions and switch between tasks, which gives them the ability to multitask efficiently. Second, they have better metalinguistic skills. This was shown in a study in which investigators gave monolingual and bilingual 5-year olds the sentence “Apples grow on noses” and asked them whether this sentence is grammatically correct. Monolingual children were able to report that the sentence was silly, but had no further insight on its grammatical structure. In contrast, multilingual children were able to recognize that the given sentence, although meaningless, was grammatically correct. Thirdly, multilingual individuals have better verbal and spatial abilities, probably a result of their metalinguistic capacity. Last but not least, the ability to speak several languages fluently has been associated with better memory skills, and research by a Canadian team suggests that bilingualism confers protection against Alzheimer’s disease. On a socioeconomic level, bilingual instruction has been associated with significant earning bonuses. Multilingualism also promotes cultural exchange and tolerance by improving communication between different groups of people.

All that being said, it appears that speaking more than one language enhances our cognition on multiple levels. With more than half of the world’s population being multilingual – that is, speaking at least two languages on a day-to-day basis – it seems relevant to reflect on who has access to instruction in multiple languages and who does not. If multilingualism is a form of cognitive enhancement and a protective measure against one of the most debilitating aging disorders, Alzheimer’s disease, how can we ensure that everyone can access it?

From www.thevici.com
Bilingual education is currently being reinvented in the United States, and research suggests that two-way immersion programs are showing results. The American Psychological Association reports that students who are part of bilingual programs such as that at The Hurley School in Boston have a better ability to pay attention in a learning environment. Furthermore, a study at Northwestern University reported reduced anxiety and better self-esteem.

Interestingly, most Americans are often surprised by the statistics, and consider multilingualism to be the exception, rather than the rule. Foreign languages are required in most schools, but not enough students achieve proficiency, at least not compared to other the levels achieved by students in other countries. Furthermore, some parents avoid teaching their children their own native language, fearing that knowledge of many languages will interfere with their children’s ability to achieve full control over any of them. This theory could not be farther from the truth. Children easily immerse themselves in multiple languages, and oftentimes obtain full speaking and reading proficiency in all of them.

Are monolingual children and adults at a disadvantage compared to their multilingual peers, and if so, are they even aware of these pitfalls in their linguistic and cognitive training? Just as scientists and bioethicists alike worry about the equal availability of cognitive enhancement drugs and technologies in the event they become legally available to the masses, so should they worry about the availability of multilingual education.

References:

Abutalebi J., Green D. (2007) Bilingual language production: The neurocognition of language representation and control. Journal of Neurolinguistics, 20(3), 242-275.

Barnett W.S., Yarosz D.J., Thomas J., Jung K., Blanco D. (2007) Two-way and monolingual English immersion in preschool education: An experimental comparison. Early Childhood Research Quarterly, 22(3), 277-293.

Craik F.I.M., Bialystok E., Freedman M. (2010). Delaying the onset of Alzheimer disease. Neurology, 75(19), 1726-1729.

Gollan T.H., Salmon D.P., Montoya R.I., Galasko D.R. (2011). Degree of Bilingualism
Predicts Age of Diagnosis of Alzheimer’s Disease in Low-Education but not in Highly-Educated Hispanics. Neuropsychologia, 49(14), 3826-3830.

Huang J., Zhu Z., Zhang J.X., Wu M., Chen H.C., Wang S. (2012). The role of left
inferior frontal gyrus in explicit and implicit semantic processing. Brain Research, 1440, 56-64.

Kovelman, I., Baker S.A., & Petitto L. (2008). Bilingual and monolingual brains compared: a functional magnetic resonance imaging investigation of syntactic processing and a possible “neural signature” of bilingualis. Journal of Cognitive Neuroscience, 20, 153-169.

Kovelman I., Shalinsky M.H., Berens M.S. & Petitto L. (2008). Shining new light on the brain’s “bilingual signature”: a functional near infrared spectroscopy investigation of semantic processing. Neuroimage, 39, 1457-1471.

Pliatsikas C., Moschopoulou E., Saddy J.D. (2015). The effects of bilingualism on the white matter structure of the brain. Proceedings of the National Academy of Science, 112(5), 1334-1337.

Schrauf R.W., & Rubin D.C. (2000). Internal languages of retrieval: the bilingual encoding of memories for the personal past. Memory and Cognition, 28(4): 616-623.

Swick D., Ashley V., Turken A.U. (2008). Left inferior frontal gyrus is critical for response inhibition. BMC Neuroscience, 9(102).

Want to cite this post?

Lucaciu, I. (2015). Is Multilingualism a Form of Cognitive Enhancement? The Neuroethics Blog. Retrieved on , from http://www.theneuroethicsblog.com/2015/05/is-multilingualism-form-of-cognitive.html

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