In a large-scale functional magnetic resonance imaging (fMRI) study, neuroscientists from MIT and Harvard University evaluated the claim of language universality with respect to core features of its neural architecture.
The language network in native speakers of diverse languages. Image credit: Malik-Moraleda et al., doi: 10.1038/s41593-022-01114-5.
Approximately 7,000 languages are currently spoken and signed across the globe.
These are distributed across more than 100 language families — groups of languages that have descended from a common ancestral language, called the proto-language — which vary in size from two to over 1,500 languages.
Certain properties of human languages have been argued to be universal, including their capacity for productivity and communicative efficiency.
However, language is the only animal communication system that manifests in so many different forms.
The world’s languages exhibit striking diversity, with differences spanning the sound inventories, the complexity of derivational and functional morphology, the ways in which the conceptual space is carved up into lexical categories and the rules for how words can combine into phrases and sentences.
To truly understand the nature of the cognitive and neural mechanisms that can handle the learning and processing of such diverse languages, scientists have to go beyond the limited set of languages used in most psycho-linguistic and neuro-linguistic studies.
To foster inclusivity in language research, Dr. Saima Malik-Moraleda and her colleagues from MIT and Harvard University examined whether there are shared brain responses across 45 languages in 12 language families: Afro-Asiatic, Austro-Asiatic, Austronesian, Dravidian, Indo-European, Japonic, Koreanic, Atlantic-Congo, Sino-Tibetan, Turkic, Uralic and an isolate, Basque, which is effectively a one-language family.
For each language, the researchers examined brain responses in one or two native speakers who listened to an excerpt of ‘Alice in Wonderland’ translated into their native tongue.
All native languages activated large areas of the left frontal, temporal and parietal cortex in the brain.
The responses of this language-related network were stronger and more correlated in the left hemisphere of the brain than the right hemisphere as subjects listened to different stories in their native languages.
The network was more responsive during listening to native languages than when performing a spatial working memory or an arithmetic task, suggesting that this common network was selective for language processing.
“This finding is a first step in deeper examinations of the neural processing of different languages, which will require larger groups of native speakers for each language,” the authors said.
Their paper appears in the journal Nature Neuroscience.
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S. Malik-Moraleda et al. An investigation across 45 languages and 12 language families reveals a universal language network. Nat Neurosci, published online July 18, 2022; doi: 10.1038/s41593-022-01114-5
