English language learners know that mastering a
new language is mentally taxing. Until recently,
however, less was known about what actually
happens inside the brains of those learning a
second language. New research findings reveal
that the brain undergoes a powerful reorganization
in bilingual individuals.
In a recent report from the journal Brain and Language, researchers from Northwestern University and the University of Houston studied brain activity of monolingual and bilingual participants. In particular, the researchers were studying a phenomenon known as phonological competition. This is the process through which we determine what word is being spoken, meaning that effective resolution of phonological competition is critical to language comprehension.
Our brains engage in phonological competition thousands of times each day. When listening to spoken English, auditory cues from the beginning of a word -- for example, “p-r-o” -- lead to activation of several possible target words (“process,” “project,” “progress,” etc.). Each of these possible targets competes for selection. As more auditory information is received, the competition becomes lower as the correct word is selected.
On a neural level, previous research suggests that each of the possible target words are activated in the brain at the same time. The brain must suppress the incorrect items to allow the correct word to be selected. Although both monolingual and multilingual individuals do this, people who know more than one language have more potential words to suppress. For example, someone bilingual in Spanish and English has significantly more words beginning with “p-r-o” to compete for selection (“progreso,” “pronombre,” etc.). Thus, bilingual children become great at suppressing incorrect information when presented with several competing choices. This translates into stronger cognitive control in math, logical reasoning, and other areas of functioning.
Novel Research Findings About Brain Structure in English Language Learners
The brain is plastic, meaning that it changes its structure and function in response to learning. Learning a new language is associated with increased brain volumes in the left parietal lobe, which is the brain’s language center. Additionally, in line with the improved cognitive control observed in bilingual people, areas of the brain that control attention and the ability to ignore distracting information also grow in size.
In conjunction with studies looking at the size of certain brain regions, researchers use functional magnetic resonance imaging (fMRI) to identify brain activity during a task. Functional MRI is a method of measuring the amount of blood flow to a brain region while a person performs a particular task. More blood flow is thought to reflect greater activation in that region compared to the rest of the brain. This allows researchers to identify which brain areas control certain abilities.
In fMRI studies, bilingualism is associated with increased activation of a network of regions throughout the brain, including the frontal, temporal, and parietal lobes. This includes the brain’s language centers, which grow larger in response to learning a new language. The network also includes regions thought to help with executive control, which allows the brain to reduce interference between the two languages being activated at a given time.
Interestingly, bilinguals show lower activation than monolinguals in the anterior cingulate cortex and left superior frontal gyrus, regions associated with executive control. This lower activation reflects improved efficiency in bilinguals; their stronger executive control abilities means that they do not need to exert as much cognitive effort to complete a task. Thus, they are better at choosing which language to use and which to ignore during a specific task.
Similarly, a study examining neural activity in native English speakers who learned Chinese for six weeks scanned the brains of participants before and after their language learning. The investigators focused on network-level differences in brain activity, which reflect the exchange of information throughout numerous brain areas. They found that successful learners had more integrated brain networks than non-learners, particularly in language-related regions. More integrated brain networks translate to faster, more efficient flow of information. This means that bilingual individuals may have structural and functional brain differences that make it easier for them to process new information.
What This Means for Instructors of English Language Learners
- English language learners aren’t necessarily slower than their monolingual counterparts (and may actually be faster!). In the study published in Brain and Language, there was no difference in reaction time between monolinguals and bilinguals. Although educators sometimes perceive that English language learners take longer to master certain tasks, this may not be the case. Bilingualism may actually make the brain more efficient at complex tasks, particularly those that involve ignoring irrelevant information.
- Increased executive control may translate to other domains of life. Numerous studies have shown that bilingual people have stronger executive control compared to monolinguals. In fact, they show larger brain volumes and more integrated brain networks in areas associated with executive abilities. This may translate to other classroom areas. For example, when presented with a math word problem that contains pieces of irrelevant information, a bilingual child may be better at ignoring distractors and finding the correct answer. English language learners may also tune out classroom distractions more effectively than their monolingual counterparts. Studies have found robust effects in which bilingual individuals outperform monolinguals across verbal and nonverbal tasks.
- Successful language use transforms the brain to a greater degree. When it comes to English language learning, the quality of education matters. An experienced educator is likely to achieve better results. Students’ successful learning results in significantly better efficiency of language networks in the brain. These efficient brain networks also improve functioning in other areas of life. This highlights the importance of investing in good educators and training programs for English language learners.
- Learning a new language results in lifelong changes to the brain. This area of brain research is relatively young, but evidence suggests that the brain changes resulting from learning a new language may last a lifetime. Thus, fostering strong abilities among English language learners may translate into a lifetime of higher cognitive control.
