From the perspective of developmental psychology and neuroscience, learning to use and understand language   (31)   a child's brain development. Through   (32)   evidence on developmentally normal children, as well as through some extreme cases of language   (33)   , that there is a "sensitive period" of language acquisition in which human infants have the ability to learn any language. Several researchers have found that the human brain may be automatically   (34)   to learn languages, while this ability does not last into adulthood in the same way that it exists during childhood. By around age 12, language acquisition has typically been   (35)   , and it becomes more difficult to learn a language in the same way a native speaker would do.