Brain Rules for Baby (John Medina) / quote 7 of 91
Fetuses turn to the outside world in late pregnancy
So the questions for prying parents become: What do fetuses know, and when do they know it? When is your baby capable of sensing, say, taps on your belly? The developmental principle to remember is this: The brain spends the first half of pregnancy setting up its neuroanatomical shop, blissfully ignoring most parental involvement. (I am referring to well-intentioned interference. Drugs, including alcohol and nicotine, clearly can damage a baby’s brain during pregnancy.) The second half of pregnancy is a different story. As brain development moves from mostly neurogenesis to mostly synaptogenesis, the fetus begins to exhibit much greater sensitivity to the outer world. The wiring of cells is much more subject to outside influences—including you—than the act of creating them in the first place.