Until the 1950s our understanding of how we learned was based almost entirely on behaviorist theories of the stimulus-response model of conditioning. Some psychologists weren’t convinced, however, and starting in 1955, American Noël Chomsky presented an alternative explanation for language acquisition. In his theory, he argued that when we learn the language, we must understand what we’re saying, not just remember a set of rules.
Chomsky found out that children progress much faster in learning languages than they would through imitation alone. They also develop an intuitive understanding of complex language structures early on. Chomsky’s work showed that all human languages share certain common features and that these are rooted in our biological nature rather than being learned. His ideas triggered a shift in focus, from behavior to cognition, in psychological research. However, for many European psychologists, his approach remained conventional.