It was widely thought, prior to the 1960s, that children acquired language through imitating their parents and other adults, who they came into early contact with. It was the work of linguist Noam Chomsky, that turned scholarship away from this Empiricist theory and toward a Nativist position on this question of how children acquired language. Chomsky saw language acquisition as an innately human ability – no other species of animal can develop language as sophisticated as human language. Language is a cognitive system; and evidence from research studies conducted over the last fifty years points towards a tacit underlying knowledge of language within human beings.
Studies included those focusing on negation in English speaking child language acquisition. The fact that children in the early stages of language acquisition avoid using negative auxiliary verbs, or use them incorrectly, in their spoken sentence structures, indicated that they were not copying their parent’s speech patterns. These results were universal in children around the ages of two to four years of age. The results of these tests found children were very creative in the ways they expressed themselves in relation to sentence negation. If parroting their parents was the preeminent means of language acquisition, then this creativity would not exist.
Chomsky founded the Universal Grammar theory, partly in response to his identification of the three main characteristics in language acquisition among children. The universality, rapidity and uniformity exhibited by all normal children in their acquisition of language, must, he thought, be based upon some structural language laws pre-programed in our genetic code. The FOXP2 gene has been identified as directly associated with language competence. This is why language emerges so effortlessly and quickly from such early ages. The stages of language development observed by researchers show babies from birth to six months cooing, then, from six months to ten months babbling, followed by, ten months to eighteen months at a one word stage, eighteen months to thirty months at a two word stage, then two and a half years to three and a half years at a multi-word stage, from three years on comes the emergence of grammar. These rates of development are astounding when compared to the development of other cognitive skills like mathematics.
Research into second language acquisition (SLA) offers linguists the chance to compare how adults acquire a second language with how children develop first language acquisition. Adults when they come to learn a second language have a fully developed cognitive system, they also have prior knowledge of the vocab and grammar of their first language and experience with explicit learning. Children have none of these things; and yet they, generally, acquire their language to a far greater level of competence, than adult SLAs. Evidence from research shows that adults initially learn faster, but in the majority of cases never acquire the fluid and perfect level that children do. My own views regarding this fact is that language acquisition is intimately associated with personal identity – how we speak is a reflection of who we are. Adults have developed personality traits and their language expresses these. Learning a new language, especially the phonological aspect of this language, demands a level of fluidity, which does exist in most fully formed adult humans. How we sound is absolutely a part of who we are.