In Part 1 of this article series, we explored natural vision correction using the methods pioneered by William H. Bates, MD. There are many books and videos available that use variations of his teachings, and some of these are listed in the bibliography included with the original Bates article.
After personally using these techniques for about a year, I had measurable changes in vision. My myopia improved to the point that my binocular acuity was equal. Before using natural vision correction, there was a difference of 200 diopters between my eyes. I was able to do away with my astigmatism completely. As I practiced the methods and tested myself, I became aware of changes in acuity that varied over time. That is, some days my vision was considerably better than on other days. For instance, while driving to work on some days I could clearly read license plates two cars away while other days the plates right in front of me were blurry. Stress always made my vision worse, and relaxation made it better. Through the natural work, I became increasingly less dependent on glasses and more comfortable with a remaining amount of blur.
Although I made improvements in acuity and comfort, I wanted to improve my ability to use binocular vision and achieve better depth perception. I looked for a Bates Method teacher in my area, but did not find one. An Internet search led me to behavioral optometry and to Dr Paul Lederer. Behavioral optometrists use special tests to determine what is causing a visual problem. Many of their clients have reading difficulty, attention deficit disorders, strabismus/amblyopia (lazy eye), or visual perceptual motor difficulty. Some behavioral optometrists use prisms and/or lenses to correct vision, while others use vision therapy with or without prisms or lenses. Some even recommend psychological therapy to deal with various levels of stress that can cause or worsen vision problems.
in July 2001, I went to Dr Lederer's office for an evaluation. This was unlike any other eye examination I had ever experienced. I discovered that visual acuity, or how well you read letters on the eye chart, is only the beginning.
There were tests of my ability to use binocular vision to fuse images from the two eyes into one, and to use that image to see depth. There were also tests for my ability to discriminate visual frequencies independent of color. "Binocular function breaks down into different frequencies like hearing. Lower spatial frequencies are more global-ambient (transient) functions for orientation, balance, and movement detection; and are faster functionally. They are predominantly for the 'where is it’ systems in the visual pathway. Higher spatial frequencies are more central-sustained functions for identification - the 'what is it’ systems in the visual pathway. Color vision is also linked to this end of the spatial frequency spectrum an these systems are slower in timing."
In addition to tests for isolated binocular function, I was tested for my ability to use vision in an integrated, functional situation. These tests involved standing while attempting to do binocular fusion using pictures and objects.
The results of these and other tests indicated that besides being myopic, I had a large muscle imbalance between the left inferior and superior oblique muscles, which pulled my left eye up and inward. This resulted in a head tilt to the left in order to keep my eyes level with the horizon. I also had abnormal retinal correspondence, which caused me to alternately focus with either the right or the left eye rather than use binocular vision. I learned that this was a neurological strategy I developed to avoid having double vision (diplopia).
Dr Lederer explained that anomalous correspondence is a rewiring in the pathway that allows more primitive binocular functions to exist even though the eyes are not in exact alignment. In my case the central vision pathways were compromised by non-concomitant motor alignment, that is muscle function, and were compensated by an anomalous correspondence sensory adaptation, which allowed optimum functions without diplopia, under the limitations of motor function. A good adaptation, but not normal. However, normal correspondence existed in the more global, lower spatial frequency pathways for orientation. Hence, therapy that focused on building more binocular function and orientation in the global aspects of vision supported improving my overall binocular functions. Dr Lederer further explained that in many cases one can achieve all that is needed to normalize visual function, while in other cases it is important to normalize functions that can be changed and compensate for others. When an individual is in control of the visual system rather that the system controlling the patient, when the patient understands their visual situation and can minimize visual stress, then limitations are not limitations.
The plan that he outlined was very much like the one used by my fellow CHEK Practitioners. That is, isolation before integration, increasing levels of neurological load, practice outside of the clinic and six week re-evaluations for progress followed by writing new therapy programs based on changes.
Because my visual problems also caused postural problems, therapy started in a seated position and progressed to standing, standing on one leg, and standing on a rocker board. The original therapy tasks used large, easy to see targets with many extra visual and auditory cues to help teach me how to see differently.
The targets progressed to become more complex and have fewer outside cues. For instance, at first I needed to use red/green glasses to do any fusion tasks because the glasses produce a color change when both eyes are used. On the other hand, I could not use polarized glasses because I did not get the color change feedback to indicate that I was using my eyes correctly. My original therapy was designed to increase my ability to diverge, or use peripheral vision. As I was able to use divergence, I was also able to use binocular vision more easily. Then I could fuse images at different distances, and combine the use of peripheral vision with a more centrally focused effort.
I had noticed that my tendency to be centrally focused made it very difficult to ride a mountain bike. I needed to see a wider visual field, to be able to see relative distance and obstacles instead of focusing on my immediate position. I worked on this in therapy using disco lights and a swinging ball as a target.
The last part of improved visual function to appear was depth perception. More than 20 therapy sessions were required before I could see depth. For most of my therapy, I did not know what the therapists were talking about when they asked if an image was "floating." When I finally saw it, I was amazed. The world looks great in 3D! Depth perception is not automatic when there is binocular vision. It is a more advanced neurological function. I still do not always see depth immediately, but now I know how.
My therapy is finished for now. At my final check up, I learned that because my visual system is in a delicate stage of balance now and might be pushed into a dysfunctional pattern by doing too much, Dr Lederer decided that therapy should stop for a while. He explained that future goals are to maintain what I have achieved and to always assure that any future gains should be considered and explored as long as they support function.
Now that my vision has improved, I am ready to continue making improvements in other systems that are also involved with my dysfunction. With the vision door open, the rest of the Totem Pole that constiutes the mind and body is also open. Other work I am using includes - but is not limited to - atlas adjustments, neromuscular therapy, cranial sacral therapy, chakra balance, acupuncture, qi gong and, of course, functional exercise.
The field of vision correction is quite broad. There are several different theories as to why visual problems occur, ranging from muscular to neurological to emotional, and they each have validity. There are also several methods for correcting vision that fit these theories and are equally valid. Vision is affected by muscle function and balance, neurological integrity, learning, emotional factors, and systemic integration of all these. Vision also affects each of these and, therefore, many body systems. The use of vision therapy is becoming more widespread as evidenced by radio ads for natural vision correction, and a recent newspaper article which reported on the use of vision therapy for improving sports performance. As more of our clients learn about this option, we will be expected to have a knowledge of it.
Just as exercise must be tailored to each individual, so should vision therapy. Due to the many influences on the visual system, therapy that is effective for one person might not be for another. Therefore, it is beneficial to clients to develop a referral network, which includes not only ophthalmologists and optometrists but behavioral optometrists and Bates instructors as well.
- Bates, W.H., The Bates Method for Better Eyesight Without Glasses, Henry Holt and Company, New York, 1981.
- Beresford, S.M., Muris, D.W., Allen, M.J., and Young, F.A., Improve Your Vision without Glasses or Contact Lenses, Simon and Schuster, New York, 1996.
- Chek, Paul. Level III Training Manual, C.H.E.K.Institute, Encinitas, CA, 1992, 1997, 2000.
- Goodrich, J., Natural Vision Improvement, Celestial Arts, Berkeley, CA, 1997.
- Lederer, Paul J., OD, and Bosse, James C., OD, Clinical Use of Contrast Sensitivity Evaluation for General Practice of Optometry, Practical Optometry, Vol 3, No1, March 1992.
- Lederer, Paul J., OD, personal communication.
- Lieberman, Jacob, OD PhD, Take Off Your Glasses and See, Three Rivers Press, New York, 1995.
- Quackenbush, T., Relearning to See, North Atlantic Books, Berdely, CA, 1997.
- Rackl, Lorilyn, (2002, February 4). The Well Trained Eye. The Daily Herald, Section 3, pp. 1,8.
- Satterfield, D., MD, Keltner, J.L., MD, and Morrison, T.L., PhD, Psychosocial Aspects of Strabismus Study, Archives of Ophthalmology, Vol 111, August 1993.