Despite the apparent diversity of languages worldwide, from English to Farsi, from Arabic to Mandarin, there is a universal language network in the brain, as revealed by a recent study from Saima Malik-Moraleda and colleagues (MIT, Harvard and Carnegie Mellon Universities in the US, and Carlton University in Canada).
A long-running criticism of linguistic research (indeed research generally) is the lack of global diversity – especially given there are around 7,000 languages being spoken today. Although there seem to be properties common to all languages, this lack of diversity has hindered attempts to establish whether different languages have differences in neural processing.
Malik-Moraleda’s study broke the mould by recruiting native speakers of 45 languages across 12 language families, such as Indo- European, Dravidian, Uralic, Austronesian and Balto-Slavic. During the tasks, the participants’ brain activity was recorded by brain imaging (fMRI).
One caveat might be that all the speakers were also bilingual in English and the preliminary baseline of locating language processing generally was carried out in English. Listeners then heard passages from Alice in Wonderland in their native language, contrasting with passages in an unfamiliar language. Non-linguistic tests of working memory and arithmetic were also included to see if there were contrasts between language and non-language processing regions of the brain.
Overall, the variation in responses between different speakers of different languages was not greater than the variation between individuals speaking the same language, implying that the brain processes all languages via the same neural circuitry. The results of brain imaging showed the same area in the left hemisphere of the brain being activated specifically for language processing across all languages – and distinct from more general intelligence.
Although this suggests that research using English speakers can be extended universally, there may still be rare processes to be detected. The authors hope to extend their work to include sign languages and more non- Indo-European spoken languages, even Esperanto and Klingon.
REFERENCE
- Malik-Moraleda, S, Ayyash, D, Gallée, J et al (2022). ‘An investigation across 45 languages and 12 language families reveals a universal language network’, Nature Neuroscience 25, 1014–1019. doi: 10.1038/ s41593-022-01114-5
