The areas of the human brain used to process language have been mapped by neuroscientists as the brain's "language network" for several decades. Located largely in the left hemisphere, this network consists of areas in Broca's area as well as other frontal and temporal lobe regions.
The vast majority of this mapping work was done by English speakers when listening to or reading English texts. Researchers from MIT have now studied brain images of 45 different language speakers. The results show that the language networks of the speakers are roughly the same as those of native English speakers.
While the results are not shocking, they do show that the location and key features of the language network are universal. The article also provides the framework for future research on linguistic features not found in English speakers, making them difficult or impossible to study in English speakers.
"This study is really fundamental, it spans a wide spectrum from English to some findings," says Fedorenko, a neuroscientist at MIT. Now that we understand that key attributes appear generic across languages, we can examine potential distinctions between languages and language families, how they exist and are processed in the brain, and things that don't actually exist in English.” form also makes statements.
Researchers require each person to complete a language challenge while scanning their brains with functional magnetic resonance imaging to identify the language network. This is because each person's unique locations and shapes of language areas differ (fMRI).
The language network must be activated by hearing or reading native language sentences. Researchers must also do tasks that shouldn't alert him, such as listening to an unknown language or solving math problems to identify this network from other brain regions.
Fedorenko began creating similar "localizing" jobs for non-English speakers a few years ago. Although English speakers are the focus of the majority of work on the language network, English does not share many features with other languages. For example, word order in English is usually fixed, although word order in other languages can vary significantly. To express additional meanings and relationships between words, most of these languages instead use the addition of morphemes or parts of words.
According to Fedorenko, various predictions are made about how English works, as well as how it works in other languages. Awareness on this issue has been increasing in recent years.
“We thought it would be helpful to create tools that would allow researchers to comprehensively study language processing in the brain in other parts of the world. Many nations now have access to neuroimaging tools, but they lack the basic paradigms needed to identify a problem in one's language-sensitive brain regions.”
The brains of two speakers of 12 different languages spanning 45 different language groups were imaged for the latest study. They wanted to see if the participants' language networks had the same location, left lobe work, and selectivity as first language speakers.
Because “Alice in Wonderland” is one of the most extensively translated literary works in the world, researchers have chosen it as the text for everyone to hear. They chose three longer pieces and 24 shorter passages, all recorded by the native speaker. In addition, each participant was read nonsense sentences that should not activate the language network, and were also given a series of other cognitive tasks to complete.
The research team discovered that the language networks of the study participants were located in approximately the same brain regions and had the same selectivity as native speakers of English.
Malik-Moraleda argues that language communities are selective. “We observed that among the speakers of the 45 languages we studied, they should not respond to other activities such as spatial working memory exercise.”
Normally active simultaneously in English speakers, frontal and temporal language centers were similarly synchronized in speakers of other languages.
The researchers also showed that the small difference they observed between speakers of various languages and all subjects was equivalent to the variation generally observed among native English speakers.
Differences and similarities
While the research suggests that speakers of different languages have a similar overall architecture of the language network, Fedorenko points out that there may still be some differences. For example, it is now possible for scholars to check for variations among speakers of languages with word order used less frequently than morphemes to define sentence meaning.
Because English has significantly less morphology than other languages, Fedorenko argues there are several interesting cases that can be made about morphological processing.
Fedorenko's lab is embarking on a study to compare the "temporal receptive fields" of speakers of six typologically different languages, including Turkish, Mandarin, and Finnish. It has been shown that the English language processing system can accommodate six to eight words at a time in terms of temporal receptive space.
Source: MIT News