What reflex causes a newborn to turn their head toward a light touch on lips or cheek?

The rooting reflex is a vital response observed in newborns that allows them to locate food and start the feeding process. When a light touch is applied to the lips or cheek, the infant instinctively turns their head toward the stimulus. This action helps them seek out a nipple for breastfeeding. The rooting reflex is essential for survival in the early stages of life, as it facilitates feeding by guiding the infant's mouth toward the source of nourishment.

The other reflexes mentioned serve different functions. The palmar reflex involves the baby's fingers closing around an object placed in their hand, which is not related to head movements in response to touch. The Moro reflex, or startle reflex, occurs when a baby feels a sensation of falling or hears a loud sound, resulting in arm spreading and then pulling back in. The startle reflex is similar, but it doesn't involve the head turning toward a touch; instead, it is a reaction to a sudden stimulus. Recognizing the distinct roles of these reflexes helps in understanding the developmental milestones of infants and their responses to their environment.