<P> The critical period hypothesis ( CPH ) states that the first few years of life constitute the time during which language develops readily and after which ( sometime between age 5 and puberty ) language acquisition is much more difficult and ultimately less successful . The hypothesis that language is acquired during a critical period was first proposed by neurologists Wilder Penfield and Lamar Roberts in 1959 and popularized by linguist Eric H. Lenneberg in 1967 . Lenneberg argued for the hypothesis based on evidence that children who experience brain injury early in life develop far better language skills than adults with similar injuries . </P>
<P> The critical period hypothesis ( CPH ) states that the first few years of life constitute the time during which language develops readily and after which ( sometime between age 5 and puberty ) language acquisition is much more difficult and ultimately less successful . The hypothesis that language is acquired during a critical period was first proposed by neurologists Wilder Penfield and Lamar Roberts in 1959 and popularized by linguist Eric H. Lenneberg in 1967 . Lenneberg argued for the hypothesis based on evidence that children who experience brain injury early in life develop far better language skills than adults with similar injuries . </P>
when does the critical period of language end
when does the critical period of language end
sometime between age 5 and puberty
sometime between age 5 and puberty