Characteristics of Infant Visual Development 1. The critical period for fetal visual development is between 20 and 40 days of pregnancy. During this period, if the expectant mother is unfortunately infected with viruses (such as rubella), suffers from a cold, is exposed to chemical substances, or uses certain medications like progesterone, it may affect the development of the eye embryo and lead to eye malformations. Therefore, expectant mothers in early pregnancy must take extra care to provide a safe and favorable development environment for their unborn babies. They should avoid viral infections, refrain from contact with chemical substances, and consult a doctor before taking any medication, clearly informing the doctor of their pregnancy. Self-medication should be strictly avoided. 2. Newborns have only 1/30 of an adult's visual acuity. A one-month-old baby can only perceive light or detect movement in front of them but cannot clearly see objects. Typically, it is not until three months after birth that babies begin to notice people, follow moving objects with their eyes, and have a visual field of about 45 degrees. They can only track objects or people horizontally within a range of 18 to 38 centimeters in front of them. 3. Protecting the eyes means protecting learning ability. Approximately 90% of the sensory information entering the human brain is acquired through vision. Children with well-developed vision absorb more, clearer, and more accurate information into their brains daily. This information helps establish neural pathways, promotes the growth of dendrites and axons in brain cells, and facilitates myelination of neural fibers. These changes enable babies to become increasingly intelligent and enhance their learning abilities. Five Details That Affect Infant Vision 4. Proper placement of toys at the baby's bedside. Many mothers like to tie a string across the crib rails and hang cute toys from it. Since babies are often farsighted, placing toys too close requires them to strain their eyes to see. Over time, prolonged inward rotation of the eyes may lead to esotropia. The correct method is to hang toys around the crib rails and frequently change their positions and orientations. Additionally, when using toys to engage the baby, avoid placing them too close to the eyes. 5. Avoid feeding in a fixed position for extended periods. When breastfeeding, it is best not to lie down or maintain a single position for too long, as babies tend to fixate on constant light sources, which can easily lead to strabismus. 6. Do not cover the baby's eyes when going outdoors. Some mothers prefer to cover their baby's eyes with a scarf or towel during sleep or when carrying them outside. This is not a good habit. Infancy is the most sensitive period for visual development, and prolonged covering of one eye may result in permanent visual abnormalities in the covered eye, known as "form deprivation amblyopia." Therefore, avoid arbitrarily covering the baby's eyes with any objects. An exception can be made when carrying the baby outdoors under strong sunlight, where a scarf can be temporarily used to shield the eyes from intense light stimulation. 7. It is best to avoid turning on lights when the baby sleeps at night. If lighting is necessary, keep it dim, cover the lamp, or direct the light toward the floor to prevent it from stimulating the eyes and affecting the baby's sleep. 8. Be mindful of excessive artificial noise in the baby's living environment. Studies indicate that noise can reduce the eyes' sensitivity to brightness and impair the stability of visual clarity. For example, when noise reaches 70 decibels, it takes 20 minutes for visual clarity to return to a stable state, while at 85 decibels, it takes at least an hour. Moreover, noise can also cause abnormalities in color vision and visual fields and disrupt the eyes' symmetrical balance response to moving objects. Therefore, avoid placing high-noise household appliances in the baby's room, and keep the volume low when watching TV or listening to music. What to Do If the Baby's Eyes Are Injured? 9. Chemical agents entering the eyes. There are various types of detergents and cleaning agents, most of which contain alkaline chemical components to varying degrees. If they accidentally enter the baby's eyes, they can damage the conjunctiva and corneal epithelium, affecting corneal transparency and causing blurred vision. Due to stimulation of the abundant sensory nerve endings in the corneal epithelium, the baby may experience photophobia, tearing, reluctance to open the eyes, and pain. Therefore, when using detergents, ensure they do not splash into the baby's eyes. If this occurs, rinse immediately with clean water. 10. Foreign objects such as sand entering the eyes. When a foreign object enters the eye, symptoms like photophobia, tearing, and reluctance to open the eyes may occur. In such cases, parents must ensure the baby does not rub their eyes, as rubbing can prevent the foreign object from coming out, scratch the corneal epithelium, embed the object deeper into the cornea, worsen pain, and increase the risk of bacterial infection and keratitis. The correct approach is to gently lift the baby's eyelid and allow tears to wash out the foreign object. If this fails, flip the baby's upper and lower eyelids to check for foreign objects on the eyelid, conjunctiva, or fornix. If present, use a sterilized cotton swab or a clean handkerchief to remove the object. If the foreign object is embedded in the cornea (commonly known as the black part of the eye) and difficult to remove, take the baby to the hospital for professional removal. Precautions to Prevent Eye Injuries 11. For babies under one year old, parents should avoid giving them toys with sharp edges. When babies start walking and running around one year of age, extra caution is needed to prevent eye injuries. Do not allow babies to handle sharp objects such as knives, scissors, needles, awls, arrows, pencils, or chopsticks, as they may fall while walking and injure their eyes with these sharp tools. 12. Do not let babies set off fireworks on their own during holidays. Since babies cannot master firework ignition techniques, the powerful force of an exploding firework can cause a series of eye injuries, such as eyelid skin and conjunctival lacerations, burns, retinal damage, and glaucoma. In severe cases, it may lead to complete blindness.