At birth, vision is one of the least developed senses. This article takes a unique family approach on vision — from birth until old age. It explains what baby sees from birth to 12 months and how parents can help infants develop good visual skills. It reviews milestones in children's visual development and explores vision care in children. It talks about vision changes in pregnancy and how to care for a parent with aging eyes.
Vision care for children: an overview
As children grow, their vision changes. Guarding children’s eye health and guiding their visual development are primary roles of parents and caregivers.
At birth, a baby’s first medical examination includes a check for congenital eye defects. Although rare, early diagnosis of these problems is important to preserve sight. Pediatrics and eye doctors (optometrists or ophthalmologists) can usually correct most eye problems – but only if spotted early.
Premature babies have a greater chance of developing certain eye problems, such as astigmatism and strabismus (misaligned eyes). Some babies are born with crossed-eyes (esotropia) – a problem that happens when eye muscles are too tight or the baby is very farsighted.
At 3 to 4 months, parents should consult an eye doctor if the baby:
- cannot focus on or follow an object with both eyes
- has difficulty moving one or both eyes in all directions
- usually has crossed eyes
- has one or both eye that tend to wander outward
From birth to age 7, one or both eyes may turn outward (exotropia) – rarely at first, then more often. The child may squint when outside in bright sun. Again, the eye muscles are responsible. Parents should consult an eye doctor.
Baby’s first visit to the eye doctor (optometrist or ophthalmologist) should occur at about 6 months. During a thorough examination, the eye doctor will test both of baby’s eyes for extreme or uneven nearsightedness, farsightedeness and astigmatism. He or she will check the baby’s eye movements and eye health. Problems with vision development and eye health are uncommon in infants, but most easily treated – if caught early.
Babies are able to see at birth. They can distinguish bright colors, masses and bold, contrasting patterns. All babies can focus on objects 8 to 12 inches away from their nose — about the distance between a baby’s and mother’s face during breastfeeding. Beyond this distance, babies cannot see clearly, but they can distinguish patches of light, large shapes and movement.
At birth, vision is one of the least developed senses. The ability to recognize what we see lies in the brain’s occipital lobe, near the back of the head. In babies, the pathways that relay information from the eye to the brain are not yet fully developed. So, at first, babies don’t really understand what they are seeing.
In the first few months of life, babies learn how to see. Focusing ability, depth perception and hand/body coordination develop rapidly.
New eye muscles need strength. In the first few weeks, babies’ eyes may wander in different directions. By 1 to 2 months, babies learn how to focus their eyes equally and track moving objects. To help out, parents can use a few simple exercises.
A newborn’s favorite sight is a face — any face. Babies would rather look at faces than anything else. They don’t yet know that faces belong to people, and they will even respond to a face drawn on a balloon.
Move close to baby’s face, then slowly from side to side. The baby will follow your movements. Moving a small rattle or simple toys, like a large kitchen spoon, from side to side will also help baby to focus on close objects.
If you talk while moving around the room, the baby will look in the direction of your voice. This action may help the baby focus the eyes equally on distant objects.
During the first month, babies prefer contrasting dark-and-light patterns to solid blocks of color. They are unable to tell the difference between similar shades, e.g., red and orange, or distinguish pastels. From 2 to 4 months, colors become more distinct, and babies begin to recognize primary shades.
Stationary crib mobiles in bright, primary colors — red, blue, green or yellow — or high-contrast patterns help develop focus. At about 2 months, babies lose interest in stationary crib mobiles and prefer to track ones that move. Brightly colored picture books and toys will begin to capture attention. Colorful wall hangings will help develop the baby’s ability to distinguish colors and shapes.
At about 2 months, when babies’ fists begin to uncurl, parents can tempt them to reach for safe, brightly colored toys. This game helps develop hand-eye coordination. When a baby holds a noisy toy, the sound attracts his or her attention — making it easier to learn the connection between what the baby sees and what the hands do.
In the third month, babies enjoy swiping at safe objects strung across the crib or hanging on a stroller. Reaching for safe, soft toys helps babies perfect hand-eye coordination.
Beginning at 4 months, babies gain more control of arm and leg movements. Depth perception, focus and object tracking skills are fine-tuned. This is the "peekaboo" and "patty-cake" time that delights parents. Hide-and-seek games are popular, as babies learn to recognize people and remember things.
By this time, babies’ eyes should work together to focus equally on objects. This ability is important for depth perception and binocular vision.
Now is the time to change babies’ toys. A safe, plastic mirror or crib-side panel with things to touch and see will hold babies’ attention longer than a mobile. Photographs or complex designs may attract more interest than colorful wall hangings. Books with big, colored pictures are a great way to exercise binocular vision.
Practice makes perfect. Reaching, touching and noisy toys are still important to develop hand-eye coordination. Swipes are gradually replaced by grabs. Babies begin to move objects from hand to mouth, so toy safety is important. Hair and jewelry are easy targets.
By 5 months, babies can spot small objects and track movements. They will turn objects over and over to get a different perspective. They are learning to recognize pastels and differences in color shades, e.g., tell red from pink.
By 8 months, babies often begin to crawl. This stage is important, because it helps babies develop the hand-eye-body-foot coordination that will soon be important for walking.
At 8 months, your baby begins to see like an adult. Near vision is still better than far vision, but babies can see a toy across a room, crawl to it, pick it up, examine it carefully, then throw it away. When they hear a noise, babies will look around a room to find out what’s happening.
Younger infants can track objects that move side-to-side or near-and-far, but 8-month-olds can track objects up-and-down. Because of their developing awareness of vertical space, babies of this age may fear heights.
Judging distances is getting easier all the time. Babies can grasp or throw things with much greater accuracy. By 12 months, babies can steer a wheel in a carseat or stroller.
By 8 months, eye color has finally changed although subtle changes may still occur. Color vision is fully developed.
Hand-eye coordination improves dramatically. Fine motor skills begin to develop. As they move into the toddler stage, babies can hold toys between the thumb and forefinger, poke or point at objects with an index finger, or reach behind their back without looking to grab a toy. Building blocks, stacking toys or very simple puzzles are good for hand-eye coordination at this stage.
By 10 months, parents may be able to tell whether their baby is right- or left-handed. At this age, books attract a lot of interest. Your baby may try to turn the pages or grab at the pictures.
Normally, parents should schedule eye examination when their child is 3 years old, then again just before school begins. Parents should consult an eye doctor if they see signs of:
- an eye that wanders inward or outward when tired
- eyelid droopiness
- redness of eyes or eyelids
- crusted eyelids
- tearing or leaky eyes
- eyelid sties or sores
- too much eye rubbing
- avoidance of bright light
Strabismus happens in about 4% of children. Often, one eye looks straight ahead but the other turns inward, outward, upward or downward. Untreated strabismus can cause a loss of depth perception or lazy eye (amblyopia).
About 2% of children have a lazy eye. Any eye problem that interferes with clear vision may slow the development of vision in one eye. Some causes are strabismus, a droopy eyelid, cataracts or refractive errors (near- or farsightedness, astigmatism).
Other vision problems, such as cataracts and glaucoma, are rare in children.
School-aged children
Most preschool and young school-aged children are slightly farsighted. Farsightedness lessens as children grow - usually stabilizing by adolescence.
Parents' first clues that their child is nearsighted often occur at school. When a child has difficulty seeing the blackboard, learning or behavioral problems often surface in class. Other clues are:
- child sits too close to television
- eye rubbing
- squinting
- clumsiness
- head held at odd angle
- headaches or dizziness
Annual eye checkups may spot nearsightedness before the child's learning or recreational activities suffer. Nearsightedness, farsightedness and astigmatism can be corrected with eyeglasses. At this age, children's vision changes quickly. Experts recommend vision checkups every 6 months for children who need eyeglasses.
The most common need for eyecare in childhood is caused by infection and injury. Pink eye (conjunctivitis) is a bacterial or viral infection that can also be caused by allergy. Parents' first experience with this common eye ailment usually occurs in daycare. Regular handwashing can prevent its spread.
Corneal scratches that affect vision may occur accidentally during rough play, particularly outside - where tree branches and other hazards can suddenly hurt the eyes.
During childhood, sports eye injuries can be prevented with proper eye protection.
During pregnancy, women’s bodies change dramatically. Hormones levels rise — a change that may affect eye health and even vision. Although eyesight usually returns to normal after delivery, women are advised to see an eye doctor (optometrist or ophthalmologist) during pregnancy to avoid eye problems.
Some eye-related changes during pregnancy are:
- a change in eyeglass or contact lens prescription
- blurry vision
- dry eye
- less tolerance of contact lenses
- a worsening of eye conditions
Vision problems during pregnancy may signal other health problems. Blurred vision may be a warning sign of gestational diabetes. Blurriness or seeing spots may indicate pregnancy-induced hypertension — an increase in blood pressure that usually occurs after the 20th week of pregnancy. Early treatment of both conditions is vital to preserve the mother’s and fetal health.
Preeclampsia and eclampsia — caused by extremely high blood pressure — can cause eye hemorrhages and retinal detachment.
Not all pregnant women develop eye problems, but some experts recommend a routine eye checkup in each trimester. Most eye-related changes disappear after birth.
As parents age, the role of caregiver passes from one generation to the next. As custodians of elderly parents, adult children are naturally concerned about their parents’ health, quality of life and ability to live independently.
Healthy eyes and good vision promote an active lifestyle. For that reason, eye health is an important concern in elderly parents. And, eye problems may be a warning sign of other diseases — e.g., high blood pressure or diabetes — common in older adults.
Low-vision aids can help elderly people with vision problems. Telescopic lenses, magnifying glasses and special light-filtering lenses are some examples of useful aids. Ask your eye doctor (optometrist or ophthalmologist) about these products.
Some changes in vision are normal. “Long-arm” syndrome (presbyopia) is a natural part of aging. Close-up objects are harder to focus on — when reading, people tend to hold books at arm’s length in order to see words clearly. People who never had glasses may now need reading glasses or bifocals or progressive lenses. To detect this change, experts recommend an annual eye examination. Presbyopia may stabilize by 65 to 70 years of age.
Floaters are tiny specks of material that “float” through the vitreous — the jelly-like substance within the eye’s globe. They often look like cobwebs, threads-like strands or spots. Floaters are very common but should be checked by an eye doctor — especially if the elderly person sees bright flashes. They may be a warning sign of retinal detachment. If there is a sudden change in the number or type of floaters, your parent should see an eye doctor.
Some eye diseases are more common in old age — e.g., glaucoma (high eye pressure), cataracts (cloudy lenses) and macular degeneration (loss of central sight). Early diagnosis and treatment of these diseases are important.
Glaucoma cannot be detected without an eye examination. Annual eye checkups are recommended to catch this thief of sight. When fluid pressure within the eye is too high, it can damage the retina — the eye’s internal projection screen. This damage can lead to permanent vision loss.
Cataracts cloud the eye’s focusing lens. They form slowly without pain. Symptoms are dim or blurry vision or a gradual loss of sight. Cataracts are treatable. The cloudy lens can be removed and replaced by a clear plastic one. However, the wait for surgery is usually long. Consult your parent’s eye doctor about the best time for lens replacement and to see whether your parent is a candidate for cataract surgery.
Retinal disorders are a leading cause of vision loss in elderly people. Macular degeneration, retinal detachment and diabetic retinopathy (ocular blood vessel disease) are disorders that affect the light-sensitive cells lining the back of the eye. When damaged, these cells cannot pass images to the brain. Consult an eye doctor, if your parent has:
- blurry central vision
- clouded vision
- inability to see faces or details clearly
- double vision
- visual distortion
- sudden vision loss
Redness, watery eyes, eye pain, loss of vision and seeing halos are symptoms of corneal disease. The cornea is the dome-shaped window that covers the eye’s pupil. Aging eyes are more vulnerable to infection, injury and other assaults on the cornea.
Temporal arteritis is a puzzling disease that occurs in the blood vessels around the temple (forehead area between the eyes and ears). No one knows its cause. It usually begins with a bad headache, pain while chewing, and temple tenderness. Weight loss, shakiness and slight fever are other symptoms. A few weeks after symptoms appear, sudden vision loss may occur. Early medical treatment may prevent vision loss in one or both eyes.
Many eye problems are treatable, especially if spotted early. An annual visit to the eye doctor is one of the best ways to maintain healthy eyesight. This visit is especially important when a parent has a history of diabetes or eye disease.
What is a black eye?
A black eye is a large bruise. It occurs when a blow or fall injures small blood vessels near the eye. The blood leaks into surrounding tissues. Applying a cold wet cloth or compress for 10 minutes will soothe a black eye and lessen swelling. A black eye changes color as it fades and usually disappears in about 10 to 14 days.
Does watching television hurt your eyes?
Watching television will not harm your vision, but it can tire your eyes, especially if room lighting is not right. If too bright, lights may reflect off the television screen, causing glare. When too dark, the contrast between the television and surrounding objects is too great, stressing your vision. Normal, soft lighting is preferable.
There is no proof that sitting too close to the television damages sight. Unlike adults, children can focus close-up without eye strain. However, in some children, sitting too close to the television may be a sign of myopia (nearsightedness).
Will eating carrots improve my vision?
Carrots are rich in vitamin A, an essential nutrient for sight. Since only small amounts of vitamin A are needed daily, most people can obtain what they need from other common foods. So, a carrot a day might keep the eye doctor away — but so will many other food sources of vitamin A. Relying on a well-balanced diet is healthier than stocking up on one nutrient source. And, too much vitamin A can be harmful.
Is it alright to wear someone else’s glasses?
Wearing eyeglasses that lack the proper prescription won’t hurt your eyes, but it won’t help them either. It won’t physically damage, weaken or strengthen your eyes — and it won’t correct your vision problem. And, wearing someone else’s eyeglasses can lead people to misjudge distances, increasing the risk of accidental falls.
Does reading in dim light hurt your eyes?
One hundred years ago, everyone read by candlelight, firelight or kerosene lamp at night. Reading in dim light does not harm or change your ability to see, but it will tire your eyes more quickly. To avoid eye strain or fatigue, good lighting is advisable.
Why do onions make you cry?
Peeling, cutting or crushing an onion releases organic enzymes called allinases. They interact with the volatile oils that give onions their distinctive flavor. Biochemical reactions create a chemical called syn-propanethial-S-oxide, which triggers tears. Its effects are strongest about 30 seconds after the onion is damaged but go away after 5 minutes. When this chemical settles on the cornea, nerve cells send an alarm signal, which the brain interprets as a burning sensation. It directs the lacrimal glands, which make tears, to wash the chemical away. “Onion tears” are born.
For more information
http://www.aoa.dhhs.gov/aoa/pages/agepages/eyes.html
http://www.scientificamerican.com/askexpert/chemistry/chemistry1.html
http://www.aoanet.org
http://www.ama-assn.org
Sources
Penelope Leach. Your Baby and Child. Alfred A. Knopf; New York, 1990
William J Benjamin, ed. Borish's Clinical Refraction. W.B. Saunders; Montreal, 1998
