There are a few different types of amblyopia (commonly referred to as lazy eye). You are probably envisioning someone you know that has a crossed or turned out eye, and it makes you uncomfortable because you’re not sure which eye they’re looking at you with. Don’t worry, even eye doctors occasionally do a double-take to make sure they are addressing the correct eye during conversation…
A more common form of amblyopia is the refractive type. This occurs when a child is born with a glasses prescription that is much stronger in one eye than the other. As the child’s vision develops, the brain wires up the clearer eye and ignores the worse eye. We call this phenomenon “suppression” of the amblyopic eye.
When an eye is suppressed during development, the vision in that eye is still blurred even when the correct prescription lens is first placed in front of it. Depth perception (also known as stereopsis or binocular vision) is not developed properly either.
Occasionally the child’s ambyopic eye and stereopsis will develop correctly simply by fitting them with a current glasses prescription. Often though, this needs to be coupled with patching of the good eye at least 2 hours per day. Eye-patching will force the brain to develop the neurological pathway needed to get the clear visual signal from suppressed eye to the back of the brain where the occipital lobe is located.
Important note: In general, the brain is mostly developed by age 9. Although it can learn new things after this age, it is not nearly as “plastic” to where it can develop a neuronal pathway from the eye to the occipital lobe. Therefore, it is extremely important to have an eye care professional perform a comprehensive examination at a much younger age. Sometimes the eye may be only mildly amblyopic, but you do not want to lose the opportunity to correct it while you can.