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Same language network across three dozen languages
Researchers gave people a roughly comparable language localizer task in each of these languages and got the same network in every case. The variability between languages was not greater than the variability between individuals who speak the same language.
The network's topography does differ from brain to brain. Yet unpublished work finds a deeper sameness: when two people listen to the same story, a region of one person's language network can be correlated against the regions of another person's brain. That picks out roughly the same network that would have been found by localizing the language network in the second person directly.
In other words, the response signatures of regions in these networks can be used to work out correspondences between people, and those correspondences line up closely with what is found at the individual level.
How can one task work in many languages?
The localizer contrasts meaningful language with a control such as nonwords or degraded speech, and each person does it in their own native language. The contrast never depends on specific words, so it carries over from one language to another. Languages differ widely in structure: English places the verb between subject and object, while Japanese puts it last. Linguists catalog roughly 7,000 living languages in the Ethnologue.
Why compare languages with individual differences?
Every brain differs from every other, so any comparison between groups has to be judged against that baseline. If speakers of different languages differed more than speakers of the same language, language would be the likely cause. The finding that they do not differ more means the differences between languages leave no larger mark than ordinary individual variation. Cortical folding patterns are unique to each person, much like fingerprints.
How can two brains be compared during a story?
The method is called intersubject correlation. Uri Hasson and colleagues reported in a 2004 Science paper that different viewers' brain responses rose and fell in synchrony while watching the same movie clip. The same logic applies to a story: when people hear the same words, regions with the same job should respond in similar patterns over time. A response pattern recorded in one person can then be used to find the matching region in another person's brain.