Everyone with what we term as “normal vision”, associates vision in terms of how good we can see and read. 20/20 is what most people think is normal or good vision; however, vision is more than being able to read letters and words. Vision is how we perceive things in our surroundings and space, it helps balance us. Vision is how we focus and relax using the eyes; as well as, what and how much we can see, and how vivid the images we see are.
Vision has its on system within the body, but it work with the ears, brain, and body to help guide you through the day. It can be responsible for a number of issues people face everyday, but we do not think that it is caused from vision. Vision can cause a person to bump into things, fall, affect overall balance, and cause reading difficulties. Headaches can be a cause of vision, and dry eyes can affect the clarity of what we see. However, we do not think in terms of vision that these things are the result of visual issues.
Sometimes vision is affected by certain eye diseases, which is when most people notice that something is wrong with their vision. What we do not expect is that “normal vision” people can also have visual issues, because as I said vision is a system and sometime that system can be interrupted. The brain is linked to the visual system, in which more than half of the surface area is dedicated to vision alone. The brain is a big part of why we have visual issues. Even if you are 20/20 acuity, your brain can cause you to see double or distorted images. Vision is at its best when the brain, eye, and ears are working in sync with one another.
The visual system is made up of two parts the central and the peripheral system. The central system is how we notice details in certain things, it is like the magnifier of the system. The central vision lets us see color, and distinguish a cup from a plate; seeing the finer details of things in life. The peripheral system is how we notices things in the background and around us, it is like the telescope of the system. The peripheral system is responsible for our orientation in space, and allows us to notice the background and surroundings of the cup. As the magnifier, the central system allows us to focus (zoom in) on the small images and distinguish the details within it. As the telescope, we are able to see the entire field of things without needing to view the miniature details. The central system is the color system, and the peripheral system is black and white and sees motion.
When the systems work together, you are able to focus on an object while still noticing the things around it. When the systems are interrupted, it can cause visual issues, but still allow a person to have 20/20 acuity. It can cause a person to only be central, where when they focus on something they are not able to notice whats going on around them. This becomes an issues when a person is driving. Yes, they are able to see enough to drive, but are they aware of the cars around them? Without the peripheral system, you could hit someone on the side of you when merging into another lane because you was not aware of them. You can also misinterpret how close or far you are from them because you are not aware of your space. Sometimes your central vision is impaired and you cannot see things as clear as you want. It can cause you to see double or have blurriness. Sometimes it might be hard for you to focus on things for a long period of time, which makes reading more difficult. Yes, you can see the words clearly, but can you focus long enough to read the entire page without having any issues? Can your eyes jump to the correct spot on the page at the right time, so that you can read the page without any difficulties? When these systems are working well and the brain is relating the correct messages, than we have a good visual system.
There are ways to help the visual system become stronger and more functional. Most people know that a pair of prescription glasses can help you see things more clearly. Sometimes you might have to couple the glasses with low vision devices (magnifiers) to help better serve your goals. Other tools that are used within glasses are prisms. Prisms helps with multiple visual issues. It shifts images, so that if a person has a visual field loss they are still able see to the images in that field. It helps with balance because it gives you a reference point in space. It can also help you process information better. Another tool to help the visual system is therapy. Therapy is used to train both systems (central and peripheral) and the brain. It is like if you brake your arm, you have to work at getting it back to a good working arm, usually through some type of therapy. The visual system works the same way, if it is interrupted somehow, therapy can help train it to be better and more functional. Like all therapy a person has to be willing to work hard to see the improvement.
Vision is more than what we can see and more complicated than just reading letters or words off a poster or screen. It has its own system within the body, and is composed of a central and peripheral system. These systems not only has to work together, but they have to work with the brain, ears, and the body. This causes us to understand our space, where a sound is coming from, and what it is we are looking at. Vision is more complicated than we understand. Anyone visual system can have flaws whether you are 20/ 600 or 20/20. If you take the time to do some therapy, invest in low vision devices and/or glasses, you can improve your overall visual system. When you take the time to understand your needs and wants out of your visual system within your lifestyle, than you can work on improving your vision to fit that. “Normal vision” is what you are satisfied with in your lifestyle, and just because you do not have an acuity of 20/ 20 does not necessarily mean your vision is not as good as you want it to be. This is a guest post by Linda after her first month working at our practice.