Parents' alertness to their baby's visual behavior is important and helps identify and diagnose the visual problem early.But even if we know that there are visual impairments, all of us, parents and professionals, we would like to have a more accurate understanding of the visual impairment and a more positive note to understand how old vision is.
By: Prof. Kent Caszlo, Professional Director at Elia – a nonprofit that specializes in the treatment of infants, toddlers and children with blindness or visual impairments.
In the first months of a baby's life, the visual system and the brain connections system develops, which is responsible for functioning and coordinating the actions of the visual system, such as: coordination of the eye, coordination between the poor, processing visual information, ability to decipher, in-depth vision and more.
Since at the time of development of the visual system, the baby is unable to speak or express his intentions clearly, it is advisable to pay attention to the visual behavior of the baby, the baby looks towards the light and is interested in toys or in his immediate environment. Toddlers who see normally are not indifferent to their surroundings and will express interest in it; Blinking exposure to strong light (sun), smiling at familiar figures, eye contact, interest in close toys, bottle, etc., are all important signs indicative of the normal development of the vision system. Sometimes, the parents, or during the follow-up tests on the milk drops or even the care team at the daycare center noticed that these gestures were not taking place properly. When there is suspicion of abnormal development of the visual system, it is important to seek a vision test.
Poor early childhood tests allow to monitor the development of the visual system and diagnose visual impairments at the earliest stage, if any. Vision affects all areas of development, it is the organizing sense that pushes us to connect with the environment, stimulates curiosity and through it we perceive and understand the world. Vision affects motor, cognitive and behavioral ability, so that the materiality and nature of the visual impairment are the important factors in the effect of visual impairment on development.
Parents' alertness to their baby's visual behavior is important and helps identify and diagnose the visual problem early.But even if we know that there are visual impairments, all of us, parents and professionals, we would like to have a more accurate understanding of the visual impairment and a more positive note to understand how old vision is.
How do I test the visual ability of newborns and babies?
The conventional measurement is called a "visual acuity test."
Usually measured in what is called a snellen fracture – 6/6, 6/12, 6/30, etc. (vision 6/6 – an object 1 cm in size from a distance of 6 meters). This measurement describes how far an object of a certain size can be identified. For older children and adults you can use a palt of letters, numbers, shapes or even images to perform the test.
But what can be done with babies and toddlers aged one, six months or even two years?
In the past, vision among infants and toddlers has checked whether the baby is staring (pixation) and following an object.
But later a test came in with an optokinetic drum, it's a cylinder with a series of varying-thick black and white stripes. When rotating the cylinder, provided that the baby sees the stripes and there is no blurring of vision, the jiggle of the poor (Nistagmus) will be caused. The degree of band density that resulted in fables in the eyes provides a measure of visual acuity.
There are currently 2 more reliable tests that can be performed for newborns and infants, which do not require much cooperation and give quality results.
One is an electrophysiological examination: a VEP test (VISUAL EVOKED POTENTIALS) – a visual brain response. In this examination the toddler sits, held in front of a computer screen that radiates changing stimuli for a short time.The toddler's head will be attached to two electrodes (one on the earlobe and the other located back on the baby's head), which record the activity that occurs in the brain at this time in the part that deals with central vision.
The second is a behavioral test-preferential look. This test originates from the Teller Acuity Cards method. This method is based on the fact that it has been shown in studies that if the baby is shown an empty target and next to a goal with an example, the baby will turn his gaze (preference) to stimulation with an example. The example of variable density stripes is typically used. Compared to gray stimulation, this method is very useful from 3 months to 2 years of age and is also usually possible until age 3. For many aged 3 and over, the stripes will not stimulate enough interest to keep the children busy and therefore have been found to be ineffective.
It is important to pay attention and follow the visual behavior of a baby already in the early stages of development. If you suspect that there are signs that indicate abnormal development in the visual system, it is important to seek a vision test with an ophthalmologist or pediatric optometrist and get more information. It is important to remember that even in early childhood and although the baby is unable to answer questions in words, today there are the tools to check visual acuity in toddlers and know what he sees.