The bilingual brain

Close your eyes and, for a moment, ideate you cognize 2 languages. For immoderate noun you tin deliberation of—object, feeling, place—two words beryllium wherever a monolingual encephalon comes up with lone one. When speaking, reading, oregon writing, your encephalon indispensable determine which of those words to use—an added task connected apical of the connection processing you’re already doing. 

Scientists fishy that sorting done those other words—and switching betwixt them—gives bilingual radical much signifier with cognitive control. But whether bilingual brains are neurologically antithetic from monolingual ones is inactive unknown. 

Saima Malik-Moraleda, a fifth-year PhD pupil successful the Harvard/MIT Program successful Speech and Hearing Bioscience and Technology, is trying to assistance reply this question. In the process, she hopes to uncover ways to easiness immoderate of the taste and governmental tensions that situation bilingualism, particularly successful cultures wherever definite languages transportation chiseled governmental connotations. As a subordinate of the McGovern Institute laboratory of Ev Fedorenko, PhD ’07, who researches however brains make language, Malik-Moraleda is studying bilingual brains successful a caller way. 

Neurobiologists typically absorption connected the comparative engagement of antithetic encephalon regions successful bilingual activity. Malik-Moraleda is taking that 1 measurement further by studying neural networks—the circumstantial pathways by which accusation travels successful the brain. Instead of simply observing which encephalon regions airy up during a peculiar activity, she uses what’s known arsenic a localized approach, tracking the reactions of circumstantial sets of neurons within—or sometimes between—those regions.

Malik-Moraleda herself speaks Spanish, Kashmiri, Catalán, English, Urdu, Hindi, and French, and she is learning Arabic. She has ever been cognizant of the taste questions that bilingualism presents. Her parent is from Spain and her begetter is from Kashmir, a disputed portion of South Asia that is claimed by some India and Pakistan. Growing up, she would walk the schoolhouse twelvemonth successful Girona, a metropolis successful Spain’s Catalonia region, and question with her begetter to Kashmir during summertime breaks. 

Splitting her twelvemonth betwixt the 2 places revealed to Malik-Moraleda however otherwise they treated bilingualism. Both regions are culturally antithetic from surrounding areas and person historically fought for independence, truthful residents often talk a region-specific connection arsenic good arsenic the superior connection of the surrounding state (or countries). On thoroughfare signs successful Barcelona, for instance, “you’re going to spot Catalán first, past Spanish, and past English,” Malik-Moraleda says. But portion Catalonians similar Catalán and thin to talk Spanish lone erstwhile necessary, successful Kashmir, she says, parents mostly discourage their children from adjacent learning Kashmiri. Instead, they impulse them to talk the much commonly utilized languages of Urdu oregon English to amended hole them for schooling and a career. 

As a polyglot child, watching her relatives neglect Kashmiri bothered Malik-Moraleda. More than sadness oregon anger, she felt confusion—why, erstwhile fixed the chance, would idiosyncratic not prehend the accidental to talk 2 languages? “It ever blew my mind,” she says. She decided to prosecute a vocation uncovering however bilingual brains really enactment truthful she could amusement her assemblage that bilingualism mightiness person immoderate invaluable advantages too. 

She began successful precocious school, penning a elder task astir bilingual brains. Then she majored successful science astatine the Autonomous University of Barcelona and spent her inferior twelvemonth astatine the University of California, San Diego. While successful San Diego, she attended a speech by MIT prof of encephalon and cognitive sciences Nancy Kanwisher ’80, PhD ’86, who mentioned the enactment of Fedorenko, a adjacent collaborator and the Middleton Career Development Associate Professor of Neuroscience astatine MIT. 

Malik-Moraleda was surviving successful New Delhi aft assemblage erstwhile she learned of the “Alice” project, a caller effort led by Fedorenko. The study, which has participants perceive to translations of passages from Alice successful Wonderland portion successful an MRI machine, aims to representation the neural networks utilized for connection processing successful speakers of arsenic galore satellite languages arsenic possible. 

Because Malik-Moraleda had entree to speakers of languages similar Hindi, Telugu, and Tamil successful New Delhi, she emailed Fedorenko, offering to help. To her surprise, Fedorenko responded wrong a day, and offered her coauthorship. “It was crazy,” she says. “That’s what led maine to beryllium like, ‘Yes, I truly privation to enactment with this person.’”

Malik-Moraleda’s enactment since she arrived astatine MIT—where she is besides advised by prof of encephalon and cognitive sciences Ted Gibson—has formed the ground of a 2021 survey with Fedorenko looking astatine enforcement relation successful bilingual people. Previous studies had yielded conflicting results astir whether bilingualism is linked to superior enforcement function, successful portion due to the fact that bilingual radical often larn antithetic languages astatine antithetic ages and talk astatine antithetic levels of proficiency. 

For their study, Malik-Moraleda and Fedorenko utilized information that the laboratory had collected by scanning people’s brains portion they completed a task related to spatial moving memory: remembering wherever a series of airy flashes had appeared connected a grid. They identified 55 bilingual and 54 monolingual subjects who were different similar, and controlled for antithetic kinds of bilingualism by including lone bilingual radical who had learned their 2nd connection earlier property six and reported a proficiency people of 4 oregon 5 connected a standard of 1 to 5. 

Previous studies had been anatomy-based, looking astatine encephalon enactment successful circumstantial regions associated with enforcement relation tasks, specified arsenic the near frontal cortex. But the near frontal cortex is associated with galore networks, including some the domain-­general multiple-demand (MD) network, which supports enforcement function, and the language-selective network, which does not. Malik-Moraleda and Fedorenko suspected that the anatomy-­based studies produced conflicting results due to the fact that they didn’t effort to place which web was being activated. 

What’s more, the nonstop boundaries of the MD web tin disagree from 1 idiosyncratic to the next, and it lone partially involves the near frontal cortex. So alternatively of simply looking for enactment successful that encephalon region, they took the localized attack and looked specifically astatine the MD network. They recovered that bilingual radical consistently showed stronger neural responses successful that web than monolingual radical did erstwhile performing the flashing-light task—and they performed better. 

Malik-Moraleda hadn’t expected the 2021 paper—which she thinks was the archetypal to usage the localized attack to survey bilingual brains—to corroborate anatomy-based studies that had showed stronger enforcement relation responses successful bilingual brains. She’d thought it mightiness amusement that determination was nary difference. 

But portion the results are exciting, Malik-Moraleda says determination could beryllium different explanations for the accrued enactment successful the MD network. For example, a batch of bilingual radical are immigrants, oregon children of immigrants, who person had to woody with much challenges successful their lives. “More information and grit,” she says, could besides beryllium linked to higher enforcement functioning. 

Under the umbrella of the Alice project, Malik-Moraleda has contributed to different high-impact connection research, including a 2022 insubstantial successful Nature Neuroscience outlining the find of similarities successful encephalon processing among speakers of divers satellite languages. The squad (on which she served arsenic pb writer with Dima Ayyash ’12, MCP ’13) reported that the connection web of the encephalon responds likewise crossed 45 languages.

“It does look similar the connection web successful the encephalon is evolved to enactment each the languages successful the world,” says Malik-Moraleda. 

One intent of the probe was to marque it easier to survey however connection works successful general—not conscionable for English speakers, who person been the subjects of astir studies to date. Other languages don’t stock each of English’s features, specified arsenic its conventions for connection order. Establishing the properties of the connection web implicit 45 antithetic languages, though, lays the groundwork for aboriginal studies of linguistic elements that mightiness beryllium hard to survey successful English speakers.

The researchers published each their fMRI information arsenic good arsenic recordings and different materials utilized successful the study, and she hopes different neurobiologists volition usage them to amended methods of studying connection and grow the fig studied. “It’s an invitation for researchers who are successful an country [where people] talk a connection that is not usually researched to usage those tools arsenic well,” she says.

“Her enactment helps physique a divers and inclusive connection probe community,” says Fedorenko, who calls Malik-Moraleda a fearless researcher and a fantastic colleague. 

After finishing her PhD, Malik-Moraleda plans to usage her probe to tackle societal and governmental problems. While she has realized that the subject down connection processing is overmuch much analyzable than she primitively imagined, she hopes that revealing the features of the bilingual encephalon volition assistance person radical similar her relatives successful Kashmir that speaking aggregate languages is simply a gift.

Malik-Moraleda would besides similar to analyse whether immoderate languages mightiness beryllium much conducive to cult-building due to the fact that of however they are structured. And she wants to survey however the brain’s effect to constructed languages—like Klingon from Star Trek oregon Dothraki from Game of Thrones—differs from its effect to earthy languages. More than anything, though, she’s committed to keeping successful caput the request to survey divers languages, which she says volition springiness researchers a much holistic knowing of connection processing. 

“We person to look astatine arsenic galore languages arsenic possible,” she says, “for america to beryllium capable to recognize connection processing successful its entirety.”