With only 25% of adult brain size at full-term birth, 90% reached by age 5, children really “are for learning.” According to one estimate (Zero-to-Three), at peak in early childhood, 250,000 neuronal connections occur every second in a child’s brain. What babies experience literally builds their brains.
But development does not happen willy-nilly. To establish systems optimally, particular experiences are needed at the right time—those that match with the baby’s maturational schedule (Gottlieb, 1991). Though parents might want to rush to teach reading to their babies with flashcards and videos, evolution set up an infant’s maturational schedule for a different kind of learning.