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Volume 12 #12 December
The new DL (Directed Lingustics) glasses are funny-looking enough so that I am getting a bunch of questions about whether people couldn’t just use the sun glasses with the right lens removed instead of the DL ones. The answer is no and there is a good reason.
Here is the problem. The corpus callosum in dyslectics is a sl0w transmitter of signals from the right side of the brain to the left, which gums up the language processing that should be going on on the left side. We can compensate for the slow transmission with ears by simply isolating words to the left brain while we send a contrasting signal (music) to the right, keeping the right busy and out of the action. This by-passes the problem of the poky CC, by simply not using it. In addition, the left side is stimulated into action because it is perforce doing the work. So we do two things at once: we stimulate the left and eliminate the delay.
How to stimulate the left and simultaneously compensate for the delay in the visual system has been more of a problem, because you can’t avoid using the CC. The DL glasses offer a different solution. Instead of trying to dodge the slow transmission, you simply speed it up! But you only want to speed up the signal that has been going slowly through the CC. Now in the visual system, the retina has two sides, the nasal side, so-called because it is nearer your nose, and the temporal side, because it is nearer your temples. The temporal side is the one that uses the CC, so that is the one we want to get cracking. When you remove the outside part of the right lens, as it is done in the DL glasses, you are giving a sightly brighter, therefore faster, input just to the right, or temporal, side of the retina.
Now you see why you don’t simply pop out the right lens of sunglasses. If you do that, you are stimulating the whole right eye, and its whole retina, giving you no difference in intensity that will speed things up. The inventor of the glasses, a Dr. Fredric Schiffer, cooked up the technique for a different reason. He had found that stimulating the left hemisphere reduced depression markedly in his patients. Together with neurologists, he had calculated exactly the amount of darker lens you want to eliminate for the maximum effect. Clever people. So we speed’em up and we cheer ‘em up. I always did love a twofer.