The Effect of a Second Language on the Brain
In this day and age of increasing global inter-connectivity, having the ability to speak more than one language is a highly valued skill. Studying a foreign language is a requirement in some schools in the U.S but in some countries, it’s the law that all students are to pass two languages before they are allowed to graduate.
Meanwhile, those who grew up learning but English are taking language classes in droves.
There is a reason, of course. Bilingualism can very well translate to better job opportunities and a better pay. In some career paths, fluency in more than one language is even an absolute requirement. And who can resist the temptation to brag about being able to speak French?
So imagine my surprise when I read that the scientific community used to believe bilingualism was bad for your brain. Dr. Colin Baker, professor of Education at Bangor University, wrote in his 1993 book Foundation of Bilingual Education and Bilingualism that around a century ago, it was believed that bilingualism could cause anything from language confusion (“cerebral confusion”), “split personality” and even spiritual decline.
He then followed up with his 1995 book, A Parents’ and Teachers’ Guide to Bilingualism, and noted that just half a century ago educators across North America used to tell immigrant parents to discourage the use of their native language at home. Practicing a second language, it was believed, could hamper the children’s ability to absorb formal education.
Just half a century ago educators across North America used to tell immigrant parents to discourage the use of their native language at home. Practicing a second language, it was believed, could hamper the children’s ability to absorb formal education.
The underlying argument for this belief was that the brain was limited in its capacity. So in learning a new language, the brain had to sacrifice some of its working capacity. Using the metaphor of a weighing scale, it was argued the study of a second language would reduce the brain’s capacity to retain knowledge of the other languages.
That era is long gone.
Many researches had since dispelled the misconceptions surrounding the disadvantages of learning a second language. Janet Werker’s (University of British Columbia), for example, compared babies who grew up in bilingual homes and those in monolingual homes.
She found that babies from bilingual homes were able to distinguish between different languages, while those from monolingual homes could not – showing that language confusion never occurred even if children were to be learn more than one language early in their lives.
In fact, various experiments since then showed that the study of foreign languages was linked to various cognitive advantages. Dumas, for example, reported in journal Child that the study of foreign language not only did not induce language confusion, it improved students’ English language skills.
In the study that involved 13,200 students in third and fourth grades of Louisiana public schools, it was apparent that students who studied a foreign language invariably did better than those who did not in the English portion of the Louisiana Basic Skill tests, regardless of their race, gender or academic level.
And if you think only young children benefits from learning a second language, consider the study conducted by T.C. Cooper and was published in The Modern Language Journal (1987). Cooper analyzed the data collected from the Admission Testing Program of the College Board and found that students who studied a foreign language in high school had better Scholastic Aptitude Test (SAT) scores, and that each year of foreign language study was found to correlate with higher verbal and math scores in the SAT test.
While those who did not study foreign language had a mean of 366 on SAT verbal test and 409 on SAT math test, those with one year of foreign language scored a little higher (378 and 416) and those with five years of foreign language scored dramatically higher (504 and 535).
There are many studies that seem to point out the correlation – but not causation – between the study of second language and improvement in overall cognitive skill. Are there any research that point to causation?
Enriching the brain
Baker challenged the earlier hypothesis that suggested our brain has a limited capacity for the acquisition of a new language. He also challenged the idea that different languages were retained in different parts of the brain (the belief was that the brain was sectioned into exclusive parts containing the knowledge of one language and with no communication or overlapping among the exclusive sections). He argued that knowledge of different languages were not kept apart. Instead, they were meshed together in our cognitive systems, and readily transferred and generalized into one another to enrich and add to the collective knowledge.
Therefore, Banker reasoned, bilingualism could boost your cognitive skills.
He further suggested that by knowing different words (in different languages) to describe one particular object or idea, the brain of a bilingual person also possessed an increased flexibility in cognitive thinking. He explained this concept by describing that in Welsh, ‘ysgol’ could mean either ‘school’ or ‘ladder’.
An English speaker who learned Welsh as a second language, then, could have an added additional dimensions to his/her cognitive thinking: the idea that school was some sort of a ladder to take one up to a better life.
Baker also found that bilingual children showed higher creativity in story-telling, which was supported by Ianco-Worrall’s research that revealed that in terms of language semantic development, bilingual children were ahead by two to three years than their monolingual peers!
Could it be that smarter students simply preferred to take up another subject? Diaz studied this issue in depth, and using statistical analysis he was able to determine that the causal link run from bilingualism to increased cognitive ability – lending support to Baker’s theory.
Better brain structures
If statistical analysis and theories, isn’t enough, consider this experiment.
In an attempt to learn more about the correlation of learning second language and its effect on the brain, Andrea Mechelli and colleagues of London’s Wellcome Department of Imaging Neuroscience along with experts from Fondazione Santa Lucia in Rome administered a brain imaging experiment on three groups of people. The first group was monolingual, the second group learned second language before the age of 5, and the third learned second language by the ages of 10 to 15.
The experiment showed that bilingual participants had denser brain tissues compared to monolingual ones. Brain tissues that showed as being denser was specifically gray matters, the tissue that made up most of the brain’s nervous cells.
This increased density was more apparent in the left hemisphere of the brain – the area responsible for language and communication skill – but is still observable in the bilingual participants’ right side of the hemisphere. (This supported the notion that the learning of second language is not merely a linguistic activity, but also a cognitive activity of the brain).
The study also found that the group who acquired second language early in their lives (before the age 5) had denser gray matter in the brain imaging experiment compared to the group who acquired second language later in life.
The researchers who published this study in the Nature journal thus concluded that the study of second language may possibly alter the structure of the human brain, and that the earlier the learning acquisition process began, the greater was the impact in the brain’s gray matter density.
Experiment showed that bilingual participants had denser brain tissues compared to monolingual ones.
What the experiment above suggested was that bilinguals may have a cognitive advantage over their monolingual peers due to better brain structures, namely the gray matters, that were more actively developed as they learned a second language, especially when they had started it early in their childhood.
Building cognitive reserve in the brain to perform at its best capacity
So far we’ve covered how bilingualism benefits children and teenagers. What about the elders? Well, experts now believe that learning a second language can help slow the onset of Alzheimer’s and dementia by increasing the brain’s cognitive reserve.
Kovelman, together with other researchers, conducted an experiment that suggests bilingualism encouraged the brain to build a cognitive reserve. He found that while different languages were processed at much of the same area of the brain (in the left hemisphere), there’s nonetheless increased activity in the right hemisphere when participants are switching back and forth between two languages.
These increased activities particularly took place in part of the brain called the “dorsolateral prefrontal cortex”, an area of the brain responsible for working memory, organization, regulation, and intellectual function, among others. (Mechelli’s, whose findings are discussed above, came to the same conclusion).
This expansion of neural activity outside of its common area when the speaker was in bilingual mode was as predictable as it was prominent on bilingual people’s brain scan, such that this phenomena was often dubbed as bilingualism’s “neurological signature”. The purpose of the neurological signature, experts argue, is to maximize the communication effectiveness of both languages.
Learning a second language, in other words, is to the brain like what exercise do to the body. It keeps the brain healthy and strong simply because it’s a cognitively challenging task.
Image by Kevin Hooley