What's New, Baby?

Click through the slideshow below to learn about the development of an infant's senses and interactions.

Sight

The newborn’s blurry vision improves rapidly. By one month of age, an infant can focus on an object up to 3 feet away. By 3 ½ months, the infant’s vision is almost as good as a young adult’s. Studies have shown that young infants prefer looking at contrasting patterns such as bull’s eyes or stripes and that they prefer the color red.

As the infant’s vision improves, it develops hand-eye coordination, the ability to reach precisely toward what it sees. This process begins at 3-4 months of age and develops throughout childhood, through activities such as coloring, tying shoes, and catching a ball.

Hearing

Hearing begins to develop before birth. At birth, a newborn can already tell the general direction a sound comes from. Although infants do not understand language, they respond to tone of voice. They are calmed by a soothing, loving voice and are alarmed by a loud or angry voice.

Because hearing is essential for language development, pediatricians suggest that babies have a hearing test by 6 months of age. Infants that were born prematurely and those who have frequent ear infections are at greatest risk for hearing impairments.

Lack of response to a loud hand clap
Lack of turning toward the source of a sound by age 3 months
Lack of awakening to loud noises, response to familiar voices, or attention to ordinary sounds

Smell

Surrounded by amniotic fluid, the fetus doesn’t have much chance to develop a sense of smell before birth. Birth brings dramatic changes. Newborns can distinguish between different odors, and within 10 days of birth can identify their mother from another person by smell.

Taste

Like the sense of smell (and for the same reason), the sense of taste develops after birth. Newborns rapidly learn to distinguish flavors. By two weeks of age, they can taste the difference between water, sour liquids, sugary solutions, salty solutions, and milk. They prefer sweet tastes to all others.

Between 4 and 6 months of age, an infant can be introduced to soft, pureed foods. In the United States, an infant’s first food is usually rice cereal. Pediatricians recommend adding new foods slowly and one at a time to see if the infant develops a skin rash or digestive upset from a particular food. These reactions are signs that the child may be allergic to that food.

During the first year, infants use their mouths to learn about their world. Because of this tendency for babies to put everything in their mouths, caregivers must be watchful.

Objects that aren’t clean can cause illness;
too small objects can cause choking;
and sharp or pointed objects can cut a baby’s mouth.

Voice

During the first year, an infant’s cry, initially shrill, becomes softer. Growth of the baby’s lungs, throat muscles, tongue, lips, teeth, and vocal cords is responsible for this change. In addition, the tongue and interior of the mouth change in shape. All these changes are necessary to prepare the infant to produce speech and to safely chew and swallow solid foods.

Babies prepare for speech by making babbling noises starting as early as 3 months of age. On average, babies are physically ready to produce speech by the end of the first year. However, they understand many words long before they are able to speak.

Teeth

The first set of teeth (also called baby teeth or primary teeth) usually begin to appear at 6 or 7 months of age. Teething, the appearance of these teeth, is typically finished by about 20 months, but this time frame varies widely.

Teething is a painful process. As each tooth forces its way through the gums, it tears the tender gum tissues. Infants who are teething tend to be cranky; they may refuse food and may drool more than usual; they may even run a low fever. Teething pain may last from 2 to 10 days for each tooth. Rubber “teething rings” or fluid-filled rings that are chilled in the refrigerator can help to ease teething pain temporarily.