Jonah Lehrer bolsters the case with a new paper from psychologist Elliot Tucker-Drob:
His main finding might, at first glance, seem somewhat paradoxical. According to the twin data, family environmental factors — the nurture side of the equation — accounted for about 70 percent of the variance in test scores for children who did not attend preschool. In contrast, those same family factors only accounted for about 45 percent of variance among children who attended preschool.
How can preschool alter the relative contribution of nature and nurture? And why does pre-k education make genetics more important? The answer has to do with the constraints on mental development.
When kids are denied an enriched environment, when they grow up in a stressed home without lots of books or conversation, this lack of nurture holds back their nature. As a result, the children are unable to reach their full genetic potential. (Razib Khan says it best: “When you remove the environmental variance, the genetic variance remains.”) The gift of preschool, then, is that closes the yawning gap between the life experiences of wealthy and poor toddlers, thus making whatever differences remain more important.
Motoko Rich looks at how Head Start affects parental behavior over time.
The Dish 