- response: loud noise or sudden change in the position of the baby’s head will cause the baby to throw his or her arms outward, arch the back, and then bring the arms toward each other as if to hold onto something
- development and course: the arm movements and arching of the back disappears over the first four to six months; however, the child continues to react to unexpected noise or a loss of bodily support by showing startle reflex (do not disappear)