NurtureShock

Excerpt from Ch. 10

Hart and Risley found that infants in welfare families heard about 600 words per hour. Meanwhile, the infants of working-class families heard 900 words per hour, and the infants of professional-class families heard 1,500 words per hour.

… This richness of language exposure had a very strong correlation to the children’s resulting vocabulary. By their third birthday, children of professional parents had spoken vocabularies of 1,100 words, on average, while the children of welfare families were less than half as articulate—speaking only 525 words, on average.

The complexity, variety, and sheer amount of language a child hears is certainly one driver of language acquisition. But it’s not scientifically clear that merely hearing lots of language is the crucial, dominant factor. For their part, Hart and Risley wrote pages listing many other variables at play, all of which had correlations with the resulting rate at which the children learned to speak. ...

If there’s one main lesson from this newest science, it’s this: the basic paradigm has been flipped. The information flow that matters most is in the opposite direction we previously assumed. The central role of the parent is not to push massive amounts of language into the baby’s ears; rather, the central role of the parent is to notice what’s coming from the baby, and respond accordingly—coming from his mouth, his eyes, and his fingers. ...