Patricia Kuhl works in a laboratory, focusing on the first critical period of development. And that is the time when babies try to control what sounds are their language. They think by studying how the sound is learned, they have models for other languages, and perhaps in critical times that may occur in childhood for social, emotional, and cognitive development. So they have studied these babies using the way we use around the world and the sounds of all languages. These babies sit on her mother's lap and they train the baby baby to turn when there is a change of voice, such as from "ah" to "ee". If they do so at the appropriate time, this black box will be bright and the panda bear will beat the drums. A six month old baby loves this job. In her opinion Babies around the world can distinguish all sounds in all languages. So the question that arises is when the world's population turns into a restricted listener culturally l ike us? And the answer is, b...