This is the first demonstration that we can choose what words the children will learn and that they can respond to them with an unfamiliar voice giving instructions in an unfamiliar setting. “(1)_____________________________why some children learn to read and write later than others,” Shaffer says, “and could lead to better treatments for developed mental problems.” What’s more, (2)_____________________________. “Language is a test case for human cognitive development,” says Shaffer, “(3)_________________________. Even without being taught new words a control group caught up with the other infants within a few months.” This is not about advancing development, he says, it’s just about what children can do at an earlier age than what educators have often thought.