Newborns

Infants are born with a number of instinctual responses to stimuli, such as light or touch, known as primitive reflexes, which gradually disappear as the baby matures. These reflexes include the:

• sucking reflex, which triggers an infant to forcibly suck on any object put in the mouth
• grasp reflex, which causes an infant to tightly close the fingers when pressure is applied to the inside of the infant’s hand by a finger or other object
• Moro reflex, or startle response, which causes an infant to suddenly throw the arms out to the sides and then quickly bring them back toward the middle of the body whenever the infant has been startled by a loud noise, bright light, strong smell, sudden movement, or other stimulus