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The Bates method for "better eyesight" is a controversial method developed by ophthalmologist William Horatio Bates, M.D. (1860-1931), which aims to undo what Bates claimed are "strained" vision habits. Bates described his approach to helping patients relax such strain (and thus, he claimed, improve their sight) in a 1920 book entitled Perfect Sight Without Glasses (or The Cure of Imperfect Sight by Treatment Without Glasses), and in his monthly magazine entitled Better Eyesight, published from 1919 to 1930.

Bates believed that various types of habitual strain originating in the mind are responsible not only for refractive errors which are usually compensated for with glasses (such as myopia, hyperopia, astigmatism, and presbyopia), but also for other abnormal eye conditions including strabismus, amblyopia, diplopia, conjunctivitis, blepharitis, cataracts, glaucoma, and diseases of the optic nerve and retina. He also claimed that "strain" was responsible for perfectly normal, and usually harmless, phenomena such as floaters. To help one's self become aware of and thereby counteract this supposed habitual strain, Bates suggested repeatedly closing and opening the eyes in front of an eye chart, visualizing objects previously seen, regularly shifting one's gaze from point to point, exposing the closed eyes to sunlight, and other activities.

Although some people claim to have been helped by following Bates' principles, his ideas remain controversial. His techniques have not been shown to objectively improve eyesight, and his main physiological theory, that the extraocular oblique muscles adjust the shape of the eyeball to maintain its focus, was rejected by mainstream ophthalmology and optometry of his day, and is still rejected today. Although most of Bates' recommendations are harmless, there is some risk that those who follow his suggestions may overexpose their eyes to sunlight, stop wearing their prescribed correction, or avoid conventional treatment when it is needed.

In Fads and Fallacies in the Name of Science, skeptic Martin Gardner characterized Bates' book as "a fantastic compendium of wildly exaggerated case records, unwarranted inferences, and anatomical ignorance." Gardner suggested that Bates' techniques may seem to work, to a limited extent, by helping one become better able to recognize blurred images.

Bates' theories

Bates developed many theories regarding vision during his career. Central to most of his theories was the thesis that "mental strain" caused poor vision. Many of his therapies rested on this assumption.

Accommodation

Accommodation is the process by which the eye increases optical power, while shifting to a closer point, to maintain focus on the retina.

Bates claimed that focus is maintained by varying elongation of the eyeball caused by the extraocular muscles, rejecting the orthodox explanation set forth by Hermann von Helmholtz, which is still accepted by mainstream ophthalmology and optometry today, that accommodation is brought about by action of the ciliary muscle (an intraocular muscle) which changes the shape of the eye's crystalline lens. Bates contended that the lens plays no part in accommodation, and asserted that the extraocular muscles, and in particular the superior and inferior oblique muscles, which are wrapped around the eye somewhat like a belt, elongate the eyeball to obtain focus at the near point, and allow the eyeball to shorten again when it looks into the distance. However, various cycloplegic agents can temporarily prevent accommodation by paralyzing only the ciliary muscle. Bates acknowledged that the effect of atropine fit the orthodox theory in "about nine cases out of ten", but argued that all "tenth cases" in which (he said) atropine failed to stop accommodation constituted strong evidence that the ciliary muscle is not actually responsible for accommodation. Critics respond that it is incorrect to base a theory on rare occurrences rather than typical ones.

To boost his theory that the extraocular muscles are responsible for accommodation, Bates cited the apparent ability of some aphakics to accommodate. Critics note that these cases are extremely rare, and therefore contend that they should be considered exceptions to the rule rather than the rule, and also cite research which indicates that there is no change in the refractive power of the eye in these cases.

Photographic evidence has shown the lens changing shape when the eye accommodates. Moreover, Berkeley optometry professor Elwin Marg, writing in 1952, pointed out that "it would take about one millimeter change in axial length of the eyeball for each three diopters change of refractive power. Hence, a youth accommodating 15 D. would shorten his globe by five millimeters" if indeed the eyeball itself changed shape to focus. He continued: "to the writer's knowledge, no corresponding anterior-posterior corneal movement has ever been reported."

Many subsequent proponents of Bates' method have expressed the view that it is unimportant whether Bates was right or wrong regarding the mechanism of eye-focusing, arguing that this is separate from his treatments, and that the proof of their effectiveness is in the results they claim to have obtained.

Cause of sight problems

Bates regarded the refractive state of the eye as variable, disregarding the mainstream view that irreversible changes in the shape of the eyeball cause refractive errors. Instead, he maintained that the eyeball's shape responds instantly to the action of the extraocular muscles upon it.

Bates regarded refractive errors as directly resulting from visual habits, and emphasized that he did not view excessive near-work as the cause of nearsightedness. Rather, he asserted that a "mental strain" to see would inhibit the eyeball from sufficiently changing shape (per his explanation of accommodation) when shifting its focus nearer or farther. He claimed that effort to see close objects instantly causes the extraocular muscles to shorten the eyeball, producing hypermetropia (farsightedness) in an eye with previously normal vision, and that effort to see distant objects instantly lengthens the eyeball, producing myopia (nearsightedness) in an eye with previously normal vision. He also stated that astigmatism is produced when these changes occur "unsymmetrically". When such "strain" becomes habitual, Bates believed, the eyes are prevented from shortening or lengthening past a certain point, and consequently the refractive error becomes constant.

Bates also linked disturbances in the circulation of blood, which he characterized as being "very largely influenced by thought", not only to refractive errors but also to diplopia, strabismus, amblyopia, and to more serious eye conditions such as cataracts and glaucoma.

The concept that "mental strain" causes sight problems is crucial to Bates' work, but is perhaps the most vague aspect of his theory. "Strain" can refer to fatigue, stress, concentration, or any other of a number of factors, making this a virtually untestable hypothesis. For example, Bates believed that the "strain" of lying could cause temporary myopia.

Eyeglasses and contact lenses

Bates cited many disadvantages to eyeglasses made in his day, maintaining that they adversely affected color perception, contracted the field of vision, and caused dizziness and headaches when the wearer viewed objects off-axis. Moreover, he maintained that the refractive condition of the eye is constantly changing, from day to day, hour to hour, and minute to minute; consequently, he reasoned, the prescribing of corrective lenses can only ever be right at the time they are fitted, after which, when they are too strong, the eye is encouraged to adjust to them (which in Bates' view meant straining more.) He thus advised that anyone wanting to improve their eyesight not wear glasses. In particular, for those attempting to apply his method on their own without the personal help of someone who had successfully used it already, he emphasized that glasses must never be worn, in any prescription.

For children, following Bates' advice not to wear glasses could jeopardize visual development. In humans the eye and brain development continues throughout childhood and into the teens. Depending on the situation, it may be necessary to correct a child's refractive error promptly in order to prevent the development of amblyopia.

Bates did not address the use of contact lenses, as they were not generally available in his day. But modern-day Bates method advocates point out that contacts are not normally removed when not needed, making them an even larger impediment to improvement than glasses, from a Bates perspective.

Bates' treatments

In his writings, Bates discussed several techniques which he reported helped patients to improve their sight, first temporarily and then, he claimed, permanently. But he wrote that "The ways in which people strain to see are infinite, and the methods used to relieve the strain must be almost equally varied", emphasizing that no single approach would work for everyone. His techniques were all designed to help dissociate strain from seeing (and were not intended to build ocular muscle strength, as is commonly misperceived.) Bates' approach centered around learning to control thoughts, as they relate to seeing. He explained that, in his view, "You can teach people how to produce any error of refraction, how to produce a squint, how to see two images of an object, one above another, or side by side, or at any desired angle from one another, simply by teaching them how to think in a particular way. When the disturbing thought is replaced by one that relaxes, the squint disappears, the double vision and the errors of refraction are corrected; and this is as true of abnormalities of long standing as of those produced voluntarily." "If the relaxation is only momentary, the correction is momentary. When it becomes permanent, the correction is permanent."

Central fixation

Only a very small part of the retina, the fovea centralis, is capable of resolving high detail, and resolution falls off with distance from the fovea. Bates asserted that "The eye with normal vision, therefore, sees one part of everything it looks at best, and everything else worse, in proportion as it is removed from the point of maximum vision; and it is an invariable symptom of all abnormal conditions of the eyes, both functional and organic, that this central fixation is lost." When central fixation is lost, he claimed, at some distances the point directly regarded appears as blurry as parts of the periphery, or even blurrier, a phenomenon he termed eccentric fixation, which he characterized as a "symptom of strain" and claimed could be relieved by "any method that relieves strain". Bates believed that "eccentric fixation" occurs when one attempts to see an area larger than a very small point equally well at once (which he believed those with sight problems are constantly doing unconsciously), and regarded "central fixation" as naturally occurring when one is not straining to see.

Flashing

Bates noted that most patients, though not all, found it easiest to relax with their eyes shut. He reported that some quickly obtained "flashes" of temporarily improved vision by alternately closing their eyes for a few minutes or longer and then opening them to a Snellen test card for a second or less. In these cases, Bates believed, the eyes were rested by being closed for a while, and the patients were eventually able to open them without immediately reasserting the strain, and were further benefited by closing their eyes again before the strain resurfaced. Skeptics acknowledge that such "clear flashes" do actually occur, but claim that they are not the result of any change in refractive power. One explanation sometimes offered is that these flashes are a contact lens-like effect of moisture on the eye (such as from tears.)

Palming

Although he did not believe that even very bright light is inherently bad for the eyes, Bates reported that most people with sight problems strain in response to light. Hence he suggested that, in addition to simply closing the eyes, an even greater degree of relaxation could be obtained in most cases by palming, or covering the closed eyes with the palms of the hands, without putting pressure on the eyeballs. If the eyes did not strain to see while palming, he said, they would see "a field so black that it is impossible to remember, imagine, or see anything blacker", since light was excluded by the palms. However, he reported that even while palming, many people continue to strain visually, and thus see "illusions of lights and colors ranging all the way from an imperfect black to kaleidoscopic appearances so vivid that they seem to be actually seen with the eyes." Some such patients, he reported, were helped by the memory of a black object (see the following subsection on memory and imagination.)

The "illusions of lights and colors kaleidoscopic appearances" reported by some of Bates' patients, and which he concluded were caused by his ubiquitous "strain", were almost certainly caused by eigengrau or "dark light". It is impossible to see absolutely "perfect" black, as the neurons of the retina and optic nerve have a "resting level" of activity, which, if the viewer succeeds in achieving total darkness, is interpreted by the brain as patterns of colour and light in the visual field. Similar hallucinations can be invoked by visual deprivation using a Ganzfeld.

Memory and Imagination

Bates reasoned that if a given object could be visualized without strain, it could likewise be seen without strain, if the strain was not reasserted as soon as the eyes were opened. He claimed that one's poise can be gauged by the visual memory of black; that the darker it appears in the mind, and the smaller the area of black which can be imagined, the more relaxed one is at the moment. He reported that some patients were benefited by thinking of the large letters on a test card and then working down to the smaller letters, and eventually to a period. But he emphasized that the clear visual memory of black "cannot be attained by any sort of effort", explaining that "the memory is not the cause of the relaxation, but must be preceded by it", and cautioned against "concentrating" on black, as he regarded an attempt to "think of one thing only" as a strain.

While Bates preferred to have patients imagine something black, he also reported that some found objects of other colors easiest to visualize, and thus were benefited most by remembering those, because, he asserted, "the memory can never be perfect unless it is easy". Skeptics reason that the only benefit to eyesight gained from such techniques is itself imagined, and point out that familiar objects, including letters on an eye chart, can be recognized even when they appear less than clear.

Shifting and Swinging

Bates felt that effort to see prevents the eyes from moving in a natural manner. He reported that "in some cases remarkable results have been obtained simply by demonstrating to the patient that staring lowers the vision and shifting improves it." Bates linked this "staring" to "eccentric fixation" (see above), and suggested consciously "shifting" to help restore "central fixation" and experience what he termed the swing, which he defined as the illusion of everything seen apparently moving in the direction opposite to which the eyes move. He claimed that "the shorter the swing" which is experienced, "the better the sight".

Bates suggested at first shifting slowly, at the distance where the sight is most clear, over areas wide enough that one can easily let go of the previous point regarded, and allowing it to develop from there. He said that "it is usually impossible, however, to realize the swing if the shifting is more rapid than two or three times a second", and felt that an overt attempt to shift rapidly would just produce more strain. He also indicated that it is usually helpful to imagine something swinging. By alternating actual and mental shifting between letters on an eye chart, Bates reported, many patients were quickly able to shorten the swing to a point where they could "conceive and swing a letter the size of a period in a newspaper."

In his Better Eyesight magazine, Bates suggested several methods of realizing and then shortening the "swing". One such technique was the long swing, which consisted of standing with the feet a foot apart, slowly turning the body alternately from left to right and right to left while raising the opposite heel off the ground, allowing the head and eyes to move with the body, without paying attention to the apparent movement of stationary objects. Bates said that at first, the long swing is the "optimum swing" because it is wide, but indicated that it can be shortened down to "the normal swing of the normal eye."

Perhaps finding Bates' concepts of "shifting" and "swinging" too complicated, some proponents of vision improvement have suggested simply moving the eyes up and down, left and right, and shifting focus between a near-point and a far-point.

Sunning

Because he believed that people who strain to see tend to strain in response to light, Bates suggested exposing the eyes to sunlight to help unlearn that strain. He claimed that "persons with normal sight can look directly at the sun, or at the strongest artificial light, without injury or discomfort", and gave several examples of patients' vision allegedly improving after having done so, which in some situations may be dangerous. Figures in Chapter 17 of Bates' Perfect Sight Without Glasses show multiple individuals looking at the Sun with "no sign of discomfort", and figure 48 shows somebody "Focussing the Rays of the Sun Upon the Eye of a Patient by Means of a Burning glass."

Bates cautioned that, just as one should not attempt to run a marathon without training, one should not immediately look directly at the sun, but he suggested that could be worked up to. He acknowledged that looking at the sun could have ill effects, but claimed they were "always temporary" (at least in the sense of being reversible) and were actually the effects of strain in response to the sunlight. He claimed to have cured people who believed that the sun had caused them permanent eye damage.

Of bright sunlight shining directly on open eyes, Bates remarked that "persons with imperfect sight usually find it impossible to accustom themselves to such a strong light until their vision has been improved by other means", though he also reported that in rare cases, sungazing alone had brought about complete cures of sight problems. Bates did temper his suggestions regarding this activity in later editions of his magazine, Better Eyesight, recommending instead that direct sunlight be allowed to shine on closed eyelids.

Modern variants

Many "self-help" books and "programs" exist claiming to improve eyesight "naturally" by various means, most having some basis in the Bates method. Modern approaches place more emphasis on breathing and posture than Bates did. Nutrition is also often mentioned as a factor in vision habits.

"Natural Vision Improvement"

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"Natural Vision Improvement" uses techniques of breathing, relaxation, and specific movements in an attempt to reverse sight problems. "Natural vision teacher" Thomas R. Quackenbush defines the Bates method thus:

An educational program created by ophthalmologist William H. Bates, M.D., in which natural, correct vision habits—based on relaxation of the mind and body—are taught; optional self-healing activities and games are often included to accelerate integration and self-healing; commonly misunderstood as only "eye exercises"—even by many "Bates Method" teachers.

The "See Clearly Method"

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The commercial See Clearly Method, marketed by the "American Vision Institute", was shut down by a court order in November 2006. While it included "palming" and "light therapy", the American Vision Institute doctors emphasized that they did not endorse the Bates method overall. Likewise, Bates method proponents have distanced themselves from the See Clearly Method.

Ophthalmological research

A review of research on "visual training" for refractive errors by the American Academy of Ophthalmology (AAO) concluded that there is "level I evidence" (from randomized controlled trials) "that visual training for control of accommodation has no effect on myopia." Other studies have shown weaker (level II/III) evidence of improvements in subjective visual acuity for patients with myopia who have undertaken visual training, but no corresponding physiological cause for the observed improvements has been demonstrated.

The AAO report states that "mainstream medicine is recognizing a need to learn more about alternative therapies and determine their true value." However, they also conclude that "the Academy believes that complementary therapies should be evaluated similarly to traditional medicine: evidence of safety, efficacy, and effectiveness should be demonstrated."

A 1946 study reported that out of 103 patients, 30 showed a "small improvement" in subjective visual acuity, 31 showed "inconsistent improvements", 32 had no change, while 10 demonstrated a worsening of acuity after visual training. Of the 61 total patients who demonstrated any improvement, 17 returned for a five-month follow-up, where it was found that two had maintained this improvement, while the other 15 had not.

Biofeedback training

In the 1980s and 1990s, interest in biofeedback stimulated some research into whether it could affect eyesight (as might be expected if "strain" were the cause of sight problems, as Bates believed.) It was found in one study that myopes could improve their visual acuity with biofeedback training, but that this improvement was "instrument-specific" and did not generalise to other measures or situations. In another study an "improvement" in visual acuity was found but the authors concluded that this could be a result of observers learning the task. Finally, in an evaluation of a training system designed to improve acuity, "no significant difference was found between the control and experimental subjects". A 1997 review of this biofeedback research concluded that "controlled studies to validate such methods ... have been rare and contradictory."

Claimed success

As their strongest evidence for the effectiveness of the Bates method, proponents point to the many accounts of people claiming to have improved their eyesight. Although there is no reason to doubt the integrity of these accounts, they are regarded by skeptics as less than conclusive, for several reasons.

• Some cases of myopia are recognized as due to a transient spasm of the ciliary muscle. These are classed as pseudomyopia; the cure would be expected to be spontaneous.
• As noted above, the "clear flashes" often spoken of by Bates enthusiasts are sometimes explained by skeptics as a contact lens-like effect of moisture on the eye.
• Recent research has shown that when subjects with myopia remove their refractive correction, blur adaptation develops to produce an improvement in their visual resolution, even though no significant change in refractive error (measured using autorefraction) is found.

• Optometrists sometimes prescribe glasses which are too strong, or not needed at all. In these cases the abandonment of such glasses may lead to improved vision.

Probably the most important argument against these accounts, however, is selection bias. This is the effect whereby spurious relationships can appear to exist because of selective reporting. In this case, many people have tried the Bates method. For some, their eyesight has improved; for some there is no change; in some cases, perhaps, their eyesight has deteriorated. If only the first of these groups publicise what has happened, and the other two groups keep silent, it will appear that the BM has been very effective, whereas in fact it may not have been.

The case of Huxley

Perhaps the most famous individual to claim successful results with the Bates method was the British writer Aldous Huxley. At the age of sixteen Huxley had an attack of keratitis punctata, which left him with one eye just capable of light perception and the other with an unaided Snellen fraction of 10/200. This near-blindness was mainly due to opacities in both corneas, complicated by hyperopia and astigmatism. He was able to read provided he dilated his better pupil with atropine and used glasses.

In 1939, at the age of 45, his eyesight began to deteriorate, and he sought the help of Margaret Corbett, who ran a "School of Eye Education" and who had trained with Dr. Bates. Three years later he wrote: "At the present time, my vision, though very far from normal, is about twice as good as it used to be."

His case attracted wide publicity. Ophthalmologist Walter B. Lancaster commented:

It is often pointed out that Huxley’s visual acuity has not improved in any extraordinary way. He admits that. The point is that he has learned how to use what he has to better advantage. It is not the primary retinal sensation that is improved; it is the neglected, but vitally important, cerebral part of seeing that has been trained.

If his ability to see had actually improved, it remained imperfect and variable. Ten years later, in 1952, Bennett Cerf was present when Huxley spoke at a Hollywood banquet, wearing no glasses and apparently reading his paper from the lectern without difficulty. According to Cerf:

"Then suddenly he faltered—and the disturbing truth became obvious. He wasn't reading his address at all. He had learned it by heart. To refresh his memory he brought the paper closer and closer to his eyes. When it was only an inch or so away he still couldn't read it, and had to fish for a magnifying glass in his pocket to make the typing visible to him. It was an agonizing moment."

Huxley himself wrote in Chapter 4 of The Art of Seeing:

"The most characteristic fact about the functioning of the total organism, or any part of the organism, is that it is not constant, but highly variable. ... People with unimpaired eyes and good habits of using them possess, so to speak, a wide margin of visual safety. Even when their seeing organs are functioning badly, they still see well enough for most practical purposes. Consequently they are not so acutely conscious of variations in visual functioning as are those with bad seeing habits and impaired eyes. These last have little or no margin of safety; consequently any diminution in seeing power produces noticeable and often distressing results.”

General Criticisms

The purported benefits of Bates' techniques are generally anecdotal, and their claimed effectiveness in improving eyesight has not been substantiated by medical research. Medical professionals argue that refractive errors are "static, anatomic conditions" caused by "structural defect of the eyeball", and as such cannot be affected by Bates' techniques or any variations thereof.

Avoidance of conventional treatment

Critics warn that faith in the Bates method could deter people with eye conditions requiring prompt care from seeking necessary medical treatment. Bates method teachers often issue a disclaimer stating that the information and instruction they provide is "for educational purposes only", explaining that they are not eye doctors and cannot diagnose or medically treat any specific eye problem.

See also

• The Art of Seeing
• Eye examination
• Eyeglass prescription
• Matthew Luckiesh
• See Clearly Method
• Pseudomyopia
• Eye exercises

References

1. ^ Gardner, Martin (1957). "Chapter 19: Throw Away Your Glasses!". Fads and Fallacies in the Name of Science. Reprint: Courier Dover. pp. 230–241. ISBN 0-486-20394-8. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
2. ^ Bates, William H. (1920). "Chapter 10: Strain". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 106–113. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
3. ^ Russell S. Worrall OD, Jacob Nevyas PhD, Stephen Barrett MD (2007-09-12). "Eye-Related Quackery". Quackwatch. Retrieved 2008-03-27.{{cite web}}: CS1 maint: multiple names: authors list (link)
4. William Bates (0ct 1919). "Floating Specks". Better Eyesight Magazine. {{cite journal}}: Check date values in: |date= (help)
5. ^ Pollack P. (1956). "Chapter 3: Fallacies of the Bates System". The Truth about Eye Exercises. Philadelphia: Chilton Co. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
6. ^ "Complementary Therapy Assessments: Visual Training for Refractive Errors". American Academy of Ophthalmology. 2008. Retrieved 2008-07-06.
7. ^ Marg, E. (1952). ""Flashes" of clear vision and negative accommodation with reference to the Bates Method of visual training" (PDF). Am J Opt Arch Am Ac Opt. 29 (4): 167–84.
8. ^ Robyn E. Bradley (2003-09-23). "Advocates see only benefits from eye exercises". The Boston Globe (MA).
9. ^ Alan M. MacRobert (1979). "HOCUS FOCUS: modern spiritualism".
10. ^ Leanna Skarnulis (2007-02-05). "Natural Vision Correction: Does It Work?". WebMD.
11. ^ Bates, William H. (1920). "Chapter 6". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 69–74. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
12. Bates, William H. (1920). "Chapter 4". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 38–53. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
13. Bettman, J . W. (1950). "Apparent Accommodation in Aphakic Eyes". Amer. Jour. Ophthal. 33: 921–928.
14. Hirsch, Monroe J. (1950). "Apparent Accommodation in Aphakia". Amer. Jour. Optom. And Arch. Amer. Acad. Optom. 27: 412–414.
15. Bates, William H. (1920). "Chapter 7". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 75–80. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
16. ^ "Exercise v. Eyeglasses". Time. 1943. {{cite journal}}: Unknown parameter |month= ignored (help)
17. ^ Bates, William H. (1920). "Chapter 9". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 89–105. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
18. William Bates (1919). "Lying a cause of myopia". Better Eyesight (September).
19. William Bates (1930). "Lying as a cause of Myopia". Better Eyesight Magazine (March).
20. Bates, William H. (1920). "Chapter 8". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 81–88. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
21. Bates, William H. (1920). "Chapter 24". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 242–245. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
22. Donahue, Sean P. (2007). "Prescribing Spectacles in Children: A Pediatric Ophthalmologist's Approach". Optometry and Vision Science. 84(2): 110–114. doi:10.1097/OPX.0b013e318031b09b. {{cite journal}}: Unknown parameter |month= ignored (help)
23. Keilman, Kate. "Reduced Lenses for Eyesight Improvement". Retrieved 2008-04-17.
24. "Webvision: Simple Anatomy of the Retina" (definition of terms), University of Utah, Webvision: The Organization of the Retina and Visual System, September 2005, Webvision.med.utah.edu webpage: Med-UtahEdu-retina.
25. "Relation Between Superficial Capillaries and Foveal Structures in the Human Retina" (with nomenclature of fovea terms), Masayuki Iwasaki and Hajime Inomara, Investigative Ophthalmology & Visual Science (journal), volume 27, pages 1698-1705, 1986, IOVS.org, webpage: IOVS-fovea-capillaries.
26. Bates, William H. (1920). "Chapter 11". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 114–122. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
27. ^ Bates, William H. (1920). "Chapter 12". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 123–135. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
28. William Bates (1922). "Fundamentals of Treatment". Better Eyesight Magazine (March).
29. ^ Balliet R, Clay A, Blood K. (1982). "The training of visual acuity in myopia". J Am Optom Assoc. 53(9): 719–24. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link)
30. R.R. Holt (1964). "Imagery: the return of the ostracized". Am. Psychol. 19: 254–264. doi:10.1037/h0046316.
31. William Bates (1926). "Memory". Better Eyesight Magazine (February).
32. ^ Bates, William H. (1920). "Chapter 13". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 136–147. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
33. ^ Bates, William H. (1920). "Chapter 15". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 159–171. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
34. William Bates (1922). "The Variable Swing". Better Eyesight Magazine (November).
35. Pollack P. (1956). The Truth about Eye Exercises. Philadelphia: Chilton Co. p. 40-44.
36. The Proceedings of the Iowa Academy of Science. 1947. p. 264-267.
37. William Bates (1926). "Swinging". Better Eyesight Magazine (January).
38. William Bates (1930). "The Optimum Swing". Better Eyesight Magazine (March).
39. ^ William Bates (1920). "Sun-gazing". Better Eyesight Magazine (June).
40. ^ Bates, William H. (1920). "Chapter 17: Vision Under Adverse Conditions a Benefit to the Eye". Perfect Sight Without Glasses. New York: Central Fixation Publish Co. pp. 183–197. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
41. Quackenbush, Thomas R. (2000). Better Eyesight: The Complete Magazines of William H. Bates. North Atlantic Books. pp. page 299. ISBN 1-55643-351-4. {{cite book}}: |pages= has extra text (help)
42. Museum of Quackery
43. Quackenbush, Thomas R. (1997). Relearning to See. North Atlantic Books. pp. page ix to 521. ISBN 1-55643-205-4. {{cite book}}: |pages= has extra text (help)
44. Jonel Aleccia (September 1999). "Ditch those glasses". Mail Tribune.
45. Quackenbush, Thomas R. (2000). Better Eyesight: The Complete Magazines of William H. Bates. North Atlantic Books. pp. page 643. ISBN 1-55643-351-4. {{cite book}}: |pages= has extra text (help)
46. Rob Murphy, Marilyn Haddrill (December 2006). "The See Clearly Method: Do Eye Exercises Improve Vision?". AllAboutVision.com.
47. Annys Shin (2006-11-06). "Seeing the See Clearly Method for What It Is". washingtonpost.com.
48. Casewatch
49. Steven M. Beresford, David W. Muris, Mara Tableman, Francis A. Young. "Clinical Evaluation of the See Clearly Method" (PDF). p. 13.{{cite web}}: CS1 maint: multiple names: authors list (link)
50. van der Werf, Esther. "Visions of Joy FAQ with statement on SCM".
51. Woods AC. (1946). "Report from the Wilmer Institute on the results obtained in the treatment of myopia by visual training". Am J Ophthalmol. 29: 28–57.
52. Randle RJ (1988). "Responses of myopes to volitional control training of accommodation". Ophthalmic Physiol Opt. 8: 333–340.
53. Gallaway M, Pearls SM, Winkelstein AM; et al. (1987). "Biofeedback training of visual acuity and myopia: A pilot study". Am J Optom Physiol Opt. 64: 62–71. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
54. Koslowe KC, Spierer A, Rosner M; et al. (1991). "Evaluation of accommotrac biofeedback training for myopia control". Optom Vis Sci. 68: 252–4. {{cite journal}}: Explicit use of et al. in: |author= (help)CS1 maint: multiple names: authors list (link)
55. G Rupolo, M Angi, E Sabbadin, S Caucci, E Pilotto, E Racano and C de Bertolini (1997). "Treating myopia with acoustic biofeedback: a prospective study on the evolution of visual acuity and psychological distress" (PDF). Psychosomatic Medicine. 59 (3): 313–317.{{cite journal}}: CS1 maint: multiple names: authors list (link)
56. Benjamin, Harry (1992). better sight without glasses. HarperCollins. {{cite book}}: Unknown parameter |origdate= ignored (|orig-date= suggested) (help) — his own case
57. Barnes, Jonathan (1999). Improve your Eyesight. Souveir Press. {{cite book}}: Unknown parameter |origdate= ignored (|orig-date= suggested) (help) — his own case, briefly
58. Mansfield, Peter (1992). The Bates Method. Macdonald Optima.— a chapter of anonymized case-histories
59. Klaus Schmid (2004). "3.2.2.1 - Relaxing and Exercising". Myopia Manual. Pagefree Pub Inc. p. 34-35. {{cite book}}: External link in |chapterurl= (help); Unknown parameter |chapterurl= ignored (|chapter-url= suggested) (help)
60. Rosenfield, Mark (2004). "Blur Adaptation in Myopes". Optometry and Vision Science. 81 (9): 657–662. doi:10.1097/01.opx.0000144743.34976.da. {{cite journal}}: Unknown parameter |coauthors= ignored (|author= suggested) (help)
61. Noel A. Brennan (1993). "Decreased Uncorrected Vision After a Period of Distance Fixation with Spectacle Wear" (PDF). American Academy of Optometry. 70 (7): 528–531.
62. Vera-Diaz, Fuensanta A. (2004). "Increased accommodation following adaptation to image blur in myopes". Journal of Vision. 4 (12): 1111–1119. doi:10.1167/4.12.10. {{cite journal}}: Unknown parameter |month= ignored (help)
63. ^ Huxley, Aldous (1942). The Art of Seeing. Macmillan.
64. van der Werf, Esther. "Visions of Joy Disclaimer". Retrieved 2008-07-16.
65. Marsh, Greg. "Vision Improvement Center: Waiver and Disclaimer". Retrieved 2008-07-16.

Further reading

• Bates, William Horatio (1920). The Cure of Imperfect Sight by Treatment Without Glasses . Central Fixation Publishing Co.
• Better Eyesight magazine published by Bates (from 1919 to 1930)
• Published medical articles written by Bates (from 1911 - 1923)

External links

• Eye-Related Quackery, from Quackwatch
• American Academy of Ophthalmology : Complementary Therapy Assessments: Visual Training for Refractive Errors 2008
• "Flashes" of clear vision and negative accommodation with reference to the Bates Method of visual training by Elwin Marg 1952

• Alternative medicine
• Ophthalmology
• Optometry