My Studies in Visual Development
My passion for Vision began with research.
When I was an undergraduate at SUNY Albany, I remember late nights and early mornings spent happily peering into a microscope. I was fortunate enough to work in the incredible laboratory of Dr. Suzannah Bliss Tieman, who studied neural visual development. Her enthusiasm for her work was infectious and it ignited my then small curiosity in vision into a lifelong passion for learning all I could on the subject.
Under her direction, I examined cross sections of the brain and measured angiogenesis, or blood vessel growth. Using a special computer aided drawing program that was superimposed with the image I was seeing in the oculars of my microscope, I could trace the length of the blood vessels in that slice of brain tissue and calculate their length. I was measuring blood vessels in the specific area of the brain that interprets vision. We were proving that when an eye was deprived of all visual information during its critical period of development, the neural connections in that ‘vision center’ of the brain would also be decreased and underdeveloped. If this part of the brain is underdeveloped, then you may not see as clearly or at as high a resolution as the average person can. You can think of it as the brain not enabling your eyes to see the world with the proper number of “pixels.”
Definition of Amblyopia
A decrease in the best corrected vision, usually in one eye, due to a “disturbance in retinal image formation” (source 1) during the critical period or during the “first ten years of human life.”
The formation of Amblyopia
When your brain and your eyes are first developing, neural connections are formed. These connections will help our brain to interpret what our eyes are seeing as well as the level of detail that they can see. If something reduces the amount of information that the eyes can take in (for example if the eye is aimed off center from where it should be looking), it lessens how much the brain can interpret and decreases the overall number of neural connections in the brain. When the visual areas of the brain are not utilized to their potential, the overall output of the brain is diminished. In other words, if something stops you from seeing great detail when your brain and your eyes are going through their critical period of development, the neural connections that you need in order to achieve good, clear vision may be reduced permanently.* You may not end up seeing 20/20 vision. The good news is, there are, of course, exceptions.
The brain has high plasticity, its “wiring” can be changed, particularly when you are young.*If you ‘exercise’ the eye as directed by your eye doctor, you can strengthen these connections and improve the resolution of your vision. Most doctors say these connections have the best opportunity to be strengthened before about eight years of age. However, there is a chance to improve your best potential vision and re-wire the brain even into your adult years but it would require more time and more intensive therapies.
Causes and Treatments
There are different causes for amblyopia, some examples are listed below:
- strabismus (an eye turn)
- when one eye has a large amount of uncorrected refractive error (nearsight, farsight or astigmatism) compared to the other eye (blurred input from one eye).
- a medical condition such as a cataract (blocked/blurred input from one eye)
Treatments for amblyopia include eliminating the cause of the amblyopia and also, strengthening the weaker of the two eyes. Strenghtening the amblyopic eye can be achieved by blocking the sight in the good eye through patching the good eye for a period of time each day or by giving eyedrops such as atropine that temporarily blur only the good eye. This essentially forces the amblyopic eye to seek more visual information, to really pay attention to what it is looking at so it can re-wire and add some new neural connections to the visual area of the brain, making your best potential vision better!
The brain is an amazing structure. The way it directs and choreographs our body and its development, is even more amazing. To learn more about amblyopia you can click here, and don’t forget to visit your eye doctor. They are happy to answer all of your questions.
Epicanthal folds of an infant or a turned eye, let your eye doctor make the call!
If you are a parent, consider bringing your baby into a participating INFANT SEE
doctor and receive a eye exam within their first year of life at no charge. Also, any time you are suspicious of problem with your child’s vision or eyes including a possible eye turn or if one or both eyes are not seeing as well as you think they should, bring your child to the eye doctor immediately. As a mother and a doctor I would advise you to, it is always a good thing to have your suspicions checked out. Keep in mind that the younger a patient is when diagnosed with amblyopia, the faster treatment can start and the better their vision will be for life! When in doubt, get it checked out!
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