Babies are born ready to learn from their environment. The most rapid period of brain development occurs in the first three years of life as the brain forms excessive connections that are later pruned away. This pruning allows the brain to become specialized and adapted to its surroundings. Parents play a key role in nurturing and nourishing their baby's development through talking and interacting with them. The use of "parentese" helps build babies' language skills as their brains are especially sensitive to sounds between ages 0-7.