A newborn baby is born helpless and needs constant care in order to survive. The newborn's first and greatest task is adjusting to the world outside the womb. The first two months of newborn growth and development are known as the neonatal period of development.

Newborn baby

The newborn baby requires a great deal of care to develop.

States of Arousal

There are five states of arousal in which newborn babies spend their time; these include regular sleep, irregular sleep, drowsiness, quiet alertness, and crying. Most of an infant's time is spent in either regular or irregular sleep (8-9 hours of each); it is during this time that the infant's brain continues to develop the necessary connections for survival and growth. Brain plasticity refers to the idea that the brain is not yet committed to specific functions. If certain areas of the brain are damaged during this sensitive period, other areas of the brain can take over and handle new functions not previously assigned to them.

Newborns use crying as a means of communication—there are different cries to elicit various responses from caregivers. Whimpers or weak crying may simply indicate the desire for attention ("pick me up and cuddle me"), whereas intense screaming could mean hunger or some other form of distress. Most parents do well at identifying their newborn's unique cry for each need; however, some infants suffer from colic and/or cry for no apparent reason.

Senses

Some of the newborn's senses are well developed at birth, whereas others take months to fully develop. For example:

• Touch—Touch is well developed at the time of birth, and infants are highly sensitive to pain. Because touch is important for bonding and emotional development, it makes sense that this is one of the infant's earliest active senses.
• Taste/Smell—Newborns have the ability to distinguish between several different tastes; sweet is the preferred taste at birth, perhaps because mother's breast milk has a sweet taste. Again, this is a basic survival mechanism—the child needs food to survive and prefers the food their mother can provide. Newborn babies can also recognize their mothers' smell and will show a preference for smells they recognize from the womb.
• Hearing—Sensitivity to sound improves greatly over the first few months of life; however, newborns recognize familiar sounds that they heard while in the womb, especially their mother's voice. Newborns prefer the human voice to other sounds, and infants as young as 3 days old can distinguish between several different sound patterns.
• Vision—Vision is the least developed of the newborn baby's senses. Newborns can only see objects or people clearly when they appear within 18 inches in front of them—usually the distance between the infant and his or her mother's face when the infant is being held. Visual acuity is very limited but develops rapidly over the next several months. Color discrimination occurs around the age of 4 months, but newborns still prefer bright colors and patterns to gray or dull ones.

Reflexes

There are several important reflexes that a newborn baby shows after birth; each has a specific duration and function. For instance:

• Rooting/Sucking—This reflex allows the baby to find the mother's nipple (or bottle nipple) in order to eat. It can be elicited by stroking the baby's cheek; the baby will turn in the direction of the stimulation and look for the nipple. Rooting (the stroking of the cheek to stimulate the feeding response) is replaced by sucking at around 4 months of age.
• Moro—The Moro reflex is thought to help babies cling to their mothers for safety and protection. If a loud banging noise is made near the baby, the baby will make an "embracing" motion (extending arms and legs then bringing them back toward the body) in an attempt to cling. This generally disappears around 6 months of age.
• Stepping—The stepping reflex prepares the baby to start walking independently. When the baby is held under the arms with their bare feet touching the ground, the newborn will make "stepping" movements with his or her legs. This generally disappears around the age of 2 months.
• Babinski—The function of the Babinski reflex is unknown, although it may have to do with walking. After stroking the bottom of the baby's foot from toe to heel, the baby's toes fan out and the foot pulls up and away toward the shin. This can last up until the end of the first year of life, though it often disappears around 8-9 months. At this point the reflex changes, and the toes curl down and the foot curls in response to the same stimulation. If the earlier Babinksi reflex is found in an adult, it can indicate some form of brain damage.