It was once thought that infants could neither learn nor remember. This is not the case, and evidence for early learning and remembering comes from several studies. In one, infants only a few hours old learned to turn their heads right or left, depending on whether they heard a buzzer or a tone. In order to taste a sweet liquid, the baby had to turn to the right when a tone sounded and to turn to the left when the buzzer sounded. In only a few trials, the babies were performing without error.