How do we know that infants remember the sounds that they heard prenatally? • After only a few days, newborn infants learn to attend to their mother's voice more than their fathers' voice • Scientists have used microphones to record intrauterine fetal environment and picked up maternal sounds, such as the mother's voice. • When young children were asked to recall the sounds they heard prenatally, they mainly described hearing their mother's voice. • Mothers read passages from Dr. Seuss's The Cat in the Hat during pregnancy, and after birth their babies increased their sucking rate to the passages.