Broca's Area and the Language Instinct

The ability to acquire a language is a unique and essential human trait. Darwin argued that language is an instinct, like the upright posture. ¹ It is well known that children acquire their mental grammar spontaneously from their parents’ speech. Forty years ago, Chomsky proposed that for generalizing from a sample of sentences to language as a whole, an innate set of mental computations is required. ² On the basis of linguistic analyses of sentence structure, he argued that a common design, called universal grammar (UG), underlies “the Babel of languages.” ³ , ⁴ This universal plan of all languages suggests a predetermined brain system. ⁵ Several functional neuroimaging studies have shown that in people who acquired two different languages before a ‘critical age,’ ⁶ an overlapping cortical representation is used for both languages. The same result has been shown for semantic processing in late bilinguals, who have an equally high proficiency for both languages. ⁷