the fact is that the brain is ke a magnet for imulation. a good example of that, w know that 6-month-olds are figure tifly citizens of the world, they can make out language sounds at all in of the languages because e brain is ready to learn a language but the brn doesn't know whether the birth landed them in beijing on london. it has to be ready to learn language. all of that changes by 12 months when the child has lost that universal language learning ability. as a result of language they've been overhearing in those kinds of soal interactions. as a result of the brain rewires itself to lear the language that the child orlanguages the child has overheard. and this is the beginning of the vocabulary that te place in the second year. all of that in the first 18 months of life. >> you say as society, whave a serious challenge. >> we do because there are two pieces of information that ought to concern . one is that the achievement gap appears as soon as child enters the school house door. we are seeing quite a significant difrence in language