Another approach to understanding visual dyslexia and autofluorescence
How the Eye and Brain Work Together
Visual dyslexics have both missing visual information and visual noise. For visual dyslexics the missing visual information and the visual noise result from autofluorescence. Below is some information about blind spots in the eye and examples of how the brain fills in missing visual information.
The results can be the same as far as the brain is concerned. The brain fills in a best guess for what the information should be.This concept of how the brain fills in missing visual information helps to explain many of the reading errors experienced by visual dyslexics.
From an evolutionary perspective, how the brain fills in the blind spots to create a seamless image works very well. The brain can generally also fill in the small blind spots caused by lack of visual information or well as the visual noise that results from autofluorescence when the image is large. A simplified explanation is that the brain assumes that the visual information it receives from areas around the missing information is the same as the information that it does receive.
A visual dyslexic sitting next to me and looking at my green garage with white trim is not likely to notice any problems when looking at the wall. Any missing visual information due to autofluorescence will be on a small scale. Since the brain fills that visual information in as green it appears normal. Any missing visual information when looking at the trim will be filled in as white and again there is no problem. What visual dyslexics often notice is that the edges where trim meets the wall or trim meets the sky appears fuzzy . While the garage is large scale, the borders where the paint changes is the only place that gives the brain problems because it can't average the different surroundings.
When the visual information you want to receive is on the much smaller scale of print any missing visual information due to autofluorescence or visual noise generated by the autofluorescence is a much greater problem. The amount and location of autofluorescence varies in individuals and individual brains will develop different coping mechanisms so it should not be a surprise that the individual problems experienced also vary.
The See Right Dyslexia Glasses restore the missing visual information and eliminate the visual noise by filtering out the wavelengths that can be phase shifted by autofluorescent proteins in the eye.
The blind spot is the area on the retina without receptors that respond to light. Therefore an image that falls on this region will NOT be seen. It is in this region that the optic nerve exits the eye on its way to the brain. To find your blind spot, look at the image below or draw it on a piece of paper:
|To draw the blind spot tester on a piece of paper, make a small dot on the left side separated by about 6-8 inches from a small + on the right side. Close your right eye. Hold the image (or place your head from the computer monitor) about 20 inches away. With your left eye, look at the +. Slowly bring the image (or move your head) closer while looking at the +. At a certain distance, the dot will disappear from sight...this is when the dot falls on the blind spot of your retina. Reverse the process. Close your left eye and look at the dot with your right eye. Move the image slowly closer to you and the + should disappear.|
|Here are some more images that will help you find your blind spot.
For this image, close your right eye. With your left eye, look at the red circle. Slowly move your head closer to the image. At a certain distance, the blue line will not look broken!! This is because your brain is "filling in" the missing information.
This next image allows you to see another way your brain fills in the blind spot. Again, close your right eye. With your left eye, look at the +. Slowly move your head closer to the image. The space in the middle of the vertical lines will disappear.
In the next two images, again close your right eye. With your left eye, look at the numbers on the right side, starting with the number "1." You should be able to see the "sad face" (top image) or the gap in the blue line (bottom image) in your peripheral vision. Keep your head still, and with your left eye, look at the other numbers. The sad face should disappear when you get to "4" and reappear at about "7." Similarly the blue line will appear complete between "4" and "7."
More images showing how our brains fill in information that is not there.
Subjective Contours: Filling the gap. Your brain tries to fill in these four pictures with images that really are not there. Do you see a: