Your Child’s Vision – Why You Should Be Concerned

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Source: Facebook / Tara Taylor

Facebook may have saved this little girl’s sight! This photo was posted to Facebook by her mother, Tara Taylor. It shows the smiling three-year-old, Rylee Taylor. Immediately, friends and family knew something wasn’t right. They suggested that she get the little girl into an eye doctor due to her white left pupil. An eye exam revealed that Rylee had a rare eye disease called Coat’s Disease, which can lead to blindness. The mother had no idea her little girl was going blind in that eye.

As eye doctors, we are very concerned with children’s vision for many reasons. Here are some of our concerns.

  • Children often don’t complain about vision problems because they have nothing to compare it to. If their vision is blurry, they figure that everyone sees like that.
  • A child’s brain is so adaptable that it will often compensate for a serious vision problem. If one eye is blurry, the brain will shut off the blurry eye and favor the good eye. Imagine never using your left arm. Eventually it becomes weak and useless. The visual system is no different.
  • A child could be blind or going blind in one eye and the parents would not even notice it. The child can still spot an airplane off in the distant sky, but may only be using one eye.
  • The refractive error or prescription of a child can change rapidly from year to year. One year they can see just fine at school and the next year their grades begin to drop. The parent determines that the child just isn’t paying attention or applying himself. But in reality, he’s doing the best he can with his increasingly blurry vision.
  • The inside of the eye lacks pain-sensing nerves. This concern applies to adults also. The outside of the eye is the most sensitive part of the body. It can sense a speck of dust on the surface. But you can have your retina pull away from the back of the eye, known as a retinal detachment, and have no pain. You can lose your side vision from glaucoma and have no idea until it’s too late and irreversible damage has been done.
By |April 4th, 2014|Children, Eye health|0 Comments

One-sided World; Bizarre Brain Injury

Imagine half of your world disappearing before your eyes in a split second. You wait for it to come back, but it never does. Everything you see is cut in half! I recently met a man that experienced this odd and rare brain condition.

This senior-aged man arrived in our practice in a wheelchair saying that he couldn’t see to his left. He had recently suffered a stroke in the right half of his brain and had lost complete function of his left arm and leg. After some testing, we discovered that indeed the entire left side of his vision was gone due to the stroke. This made sense since the right brain receives left side vision information.

By |May 14th, 2008|Makes you go hmm, Physiology|0 Comments

Visual Auto-Completion

Have you ever had the annoyance of typing away on your word processor and had it automatically “correct” something you knew was already correct? My favorite is when I type “i.e.” and it thinks I meant to type “I.e.” Your computer thinks it’s smarter than you are. I’d like to think I’m smarter than it.

Your brain also has a built-in auto-completion or auto-correction function. And just like your word processor it often auto-corrects correctly and sometimes not. Here’s an example when it guesses incorrectly.

By |April 7th, 2008|Illusions, Physiology|0 Comments

We See Only What We Want to See

You may remember me talking about brain filtering; how our brain filters out what it doesn’t want to pay attention to. You could call it “selective sight”. For you married individuals out there, this is similar to “selective hearing” that plagues inattentive spouses. (I know I’m guilty of it.) I ran across some fun experiments that illustrate this phenomenon.

Simply put, the brain would get overloaded if it analyzed in detail everything we saw. Therefore, it ignores much of what the eyes see. Here’s a video I think you’ll find interesting.

The next video was shown to me in optometry school a few years ago. Play along and do the experiment yourself while watching the video. You’ll be amazed! Just click on this link. While watching the video, try to count the number of times the basketball is passed. Then watch it again, but this time just watch the video.

By |March 8th, 2008|Illusions, Makes you go hmm|0 Comments

The Amazing Moon Illusion

One of my favorite illusions involves the moon. It’s common knowledge that the moon looks huge when close to the horizon, but appears smaller when higher in the sky. Many theories have attempted to explain this phenomenon. (Feel free to read about them on Wikipedia. However, the article wasn’t written in layman’s terms and can be confusing.)

a-blue-moon_small.jpgThe moon is actually the same size regardless of where it is in the sky. To prove this just take a picture of it at the horizon and at other positions and compare the size in the pictures. It is not an illusion caused by the atmosphere, as commonly believed. The illusion occurs at the brain level and deals with the brain’s inability to judge large distance differences.

To understand this you have to realize that the brain manipulates image sizes in an attempt to match up the image with the relative distance from the viewer. Here’s an example. Have someone lay down on their back on the floor. Take a picture of them by aiming the camera so that their feet are in the foreground and their head is in the background. Notice how small the person’s head is in the picture. Now assume the same position you were in to take the picture, but this time without the camera. Notice that the person’s head doesn’t look as small.

Your brain realizes that their head isn’t that far away from their feet, so it “enlarges” the head to match the perceived distance. The camera, on the other hand, doesn’t realize the head is only about 5 feet away from their feet and fails to match up the head size with the short distance. Now imagine the horizon is the “feet” and the moon is the “head”. Your brain doesn’t realize that the moon is actually 200,000 miles away. It sees it as being just beyond the horizon. Therefore, it “enlarges” the image of the moon just like it did with the person’s head.

Truly amazing!

By |November 21st, 2007|Illusions|0 Comments