As you can see in the above diagram, the visual system works like a camera.
- the lens: a crystalline lens that receives light through the clear cornea and helps focus light on the retina.
- film (or a digital recorder): the retina, located along the back curve of the eyeball, on which the lens focuses light from the object seen.
- a connector: the optic nerve, which carries recorded light and colors from the retina to the brain.
- A developing or processing center: the brain, which organizes the light into pictures (images) and recognizes that these images represent objects in the outside world.
Seeing well is similar to taking a good picture with a camera. If the retina is not stimulated enough during infancy and early childhood, it is as if the lens cap were left on or the camera unfocused. The picture recorded will be blank or blurry, or will have poor quality. If there is a problem with the connecting optic nerve, information recorded by the retina will not be correctly sent to the brain. Because we really see with our brains, normal eyesight will develop only if the eye, the nerves between the eye and the brain, and the brain itself are properly stimulated.
We see with our brains?
Babies are born with trillions of nerve cells (neurons) in their brains. As infants grow, these neurons join into “networks” or “circuits” that perform various functions. Some neural networks are pre-formed at birth, but others develop as the child grows and experiences the outer world. Scientists believe that there are critical periods in the development of the brain. During these periods, the child’s environment can influence how the growing brain is “wired” with the basic circuitry needed to learn important skills, such as math, logic, music, and vision. If the brain does not receive enough stimulation during the critical period for a skill to grow, this skill may be poorly developed later on. The first 2 years of life are believed to be the critical period for developing good vision, though in fact this period may be longer.
How can we sufficiently stimulate the brain, the eyes, and all of the other important parts of the visual system during and after the critical period of infancy? As we explain later, well-designed toys, games, developmental programs and DVDs, and above all interesting surroundings, all help. But sometimes, despite our best efforts, a child can miss a step in visual development. This is why for all babies, a comprehensive eye evaluation by an optometrist or an ophthalmologist by age 14 months is recommended by the American Academy of Pediatric Ophthalmologists and Strabismus.
From birth through 6 months
- The visual system (eyes, nerves, and brain) is the most complex of our five senses, but also the least developed at birth. Babies are born auditory dominant. This means that they hear better than they see, touch, feel, or smell. Your baby has listened to your voice while in the womb, and so, after birth, responds to your voice long before recognizing your face. Newborn and very young babies are listeners rather than lookers. This auditory-dominant stage lasts from birth until 2 months of age.
- Infants are born with poor vision. What a baby can see at 20 feet, an adult with normal adult vision can see at 400 feet (20/400 vision).
- Young babies can see most colors (though not blue), but they don’t see the boundaries between colors (objects) very well. A new baby has a hard time seeing that one object is separate from another. In a normal healthy newborn, the eyes will focus on a spot 8 to 10 inches in front of the baby’s face. This focus will lead to normal visual development. If the eyes focus elsewhere, vision will not develop correctly.
- A young baby’s eye movements are often described as “doll like.” This is because the six muscles around each eye that control eye movement (the extra-ocular muscles ) are not fully developed. These muscles work with one another and with the same ( yoked ) muscles around the other eye to locate and lock onto objects.
- By 2 months after birth, vision replaces hearing as the dominant sense, and the visual system begins to develop very quickly. Babies become able to focus their eyes on objects as the objects move.
- At 2 to 3 months, babies can detect small changes in brightness (contrast sensitivity develops).
- When 3 months old, your baby will see better (have better visual acuity) and begin to recognize familiar faces. Three-month-olds can lock onto a face across a room and follow a voice while the speaker is moving.
- At 3 to 4 months, color vision is getting better. Baby is developing the ability to distinguish between shades of light and dark (contrast sensitivity) and to see the boundaries between objects.
- Approaching 6 months of age, eye movements become more controlled and deliberate. The six muscles around each eye that control movement and hold the eyes steady on an object (fixation) are stronger and more coordinated.
- By 6 months of age, depth perception (stereopsis) has developed. Baby can see objects that are far away and in the middle distance, as well as close up (babies’ eyes can accommodate), and can tell that more distant objects are beyond reach.
Tips to help develop your baby’s vision from birth through 6 months
- Change the location and alignment of the crib in the room every few weeks. This will give your baby practice in seeing light from a variety of angles.
- Change your baby’s position in the crib, so light stimulates each eye and each side of the retina in each eye.
- When your baby is in the crib, talk to him or her from different positions in the room. This helps to establish the hearing-to-seeing connection, by which a baby uses its more developed hearing to refine its ability to locate objects with its eyes.
- Hang a mobile on one side of the crib, then switch it to the other side after a while, and then continue to change sides every so often. This will keep your baby intrigued with a changing and challenging environment.
- For the same reason, change and feed your baby from alternate sides.
- Keep “reach and touch” toys within 8 to 12 inches of your baby. Make sure these toys are large enough so baby can’t swallow or choke on them! To stimulate your baby, toys should have different textures, sizes, and shapes.
- Protect your baby’s eyes from the sun using a hat with a brim, children’s (pediatric) sunglasses, or both.
- Talk to your baby while looking into his or her eyes. Eye contact is very important for proper visual and psychological development. A baby’s favorite and most stimulating image for the first few months after birth is its mother’s face.
- Move your baby’s hands in front of his or her face slowly, so that baby can see and learn to follow the movement.
- Place a rattle in your baby’s hand and shake it slowly. Don’t be discouraged if your child is not interested right away. Keep doing this anyway, so baby can practice locating the rattle using the hearing-to-seeing connection. “Rattle socks” are a great toy for this age!
- If your baby seems entranced by particular movements or sounds, encourage this experience; don’t try to get baby interested in something else. Remember, during the first few months of life, hearing is a baby’s strongest sense, and babies will be stimulated and intrigued by sounds, including all sorts of music. Let your child explore visual and auditory life without constant distraction or coaching. Babies often react to the visual and musical components of the BabyEyesT DVD with this sort of fascination, actively engaging in exploring and discovering the worlds of vision and sound all by themselves.
From 6 to 12 months
- By the age of 6 months, a baby can recognize familiar faces and objects. The central part of retina (the fovea centralis), which sees fine detail and color, is being formed.
- Visual acuity is almost as good as in adults.
- Eye movement is no longer doll-like, but resembles that of adults.
- Color vision is nearly as good as in adults.
- Hand-eye coordination is developing-the ability to move the hands to where the vision directs.
- Baby can recognize individual people and smile just for them (selectively).
- Baby switches from preferring the familiar to wanting new and exciting things to happen.
- Although baby has switched from an auditory-dominant mode to a stronger visual orientation, stimulation by spoken words and sounds, particularly music, continues to play an important role in baby’s developing perceptions and mental skills.
Tips to help develop your baby’s vision from 6 to 12 months old
- Move the mobile closer to your baby to encourage the action-reaction response. Action: baby will hit the mobile and the objects will swing and bounce up and down. Reaction: baby will follow and respond to the movement of the mobile.
- Play the “please and thank you game.” Hand baby a toy and say “thank-you.” Then ask for the toy back and say “please.” Your child will develop hand-eye coordination faster when you combine visual stimulation with voice sounds (auditory input).
- Play “peek-a-boo.” This will stimulate several senses, combining seeing with hearing and feeling, to accelerate your baby’s visual and combined sensory abilities.
- Explore different textures with your child. Let baby touch different surfaces in your home, such as the border between carpet and tile, to help connect how things look to how they feel.
- Use other appropriate sight, sound, and musical experiences, such as those provided by the BabyEyes DVD, to further stimulate your child’s developing visual abilities.
- Do not rush your baby into walking. Crawling is important: it helps to develop coordination between the eyes and the body.