Bates Method - How To Improve Eyesight
The Bates method is an alternative therapy aimed at improving eyesight. Eye-care physician William Horatio Bates, M.D. (1860â"1931) attributed nearly all sight problems to habitual strain of the eyes, and felt that glasses were harmful and never necessary. Bates self-published a book, Perfect Sight Without Glasses, as well as a magazine, Better Eyesight Magazine, (and earlier collaborated with Bernarr MacFadden on a correspondence course) detailing his approach to helping people relax such "strain", and thus, he claimed, improve their sight. His techniques centered on visualization and movement. He placed particular emphasis on imagining black letters and marks, and the movement of such. He als o felt that exposing the eyes to sunlight would help alleviate the "strain".
Despite continued anecdotal reports of successful results, including well-publicised support by Aldous Huxley, Bates' techniques have not been objectively shown to improve eyesight. His main physiological propositionâ"that the eyeball changes shape to maintain focusâ"has consistently been contradicted by observation. In 1952, optometry professor Elwin Marg wrote of Bates, "Most of his claims and almost all of his theories have been considered false by practically all visual scientists." Marg concluded that the Bates method owed its popularity largely to "flashes of clear vision" experienced by many who followed it. Such occurrences have since been explained as a contact lens-like effect of moisture on the eye, or a flattening of the lens by the ciliary muscles.
The Bates method has been criticized not only because there is no good evidence it works, but also because it can have negative consequences for those who attempt to follow it: they might damage their eyes through overexposure of their eyes to sunlight, put themselves and others at risk by not wearing their corrective lenses while driving, or neglect conventional eye care, possibly allowing serious conditions to develop.
Underlying concepts
Accommodation
Accommodation is the process by which the eye increases optical power to maintain focus on the retina while shifting its gaze to a closer point. The long-standing medical consensus is that this is accomplished by action of the ciliary muscle, a muscle within the eye, which adjusts the curvature of the eye's crystalline lens. This explanation is based in the observed effect of atropine temporarily preventing accommodation when applied to the ciliary muscle, as well as images reflected on the crystalline lens becoming smaller as the eye shifts focus to a closer point, indicating a change in the lens' shape. Bates rejected this explanation, and in his 1920 book presented photographs that he said showed that the image remained the same size even as the eye shifted focus, concluding from this that the lens was not a factor in accommodation. However, optometrist Philip Pollack in a 1956 work characterized these photographs as "so blurred that it is impossible to tell whether one image is larger than the other", in contrast to later photographs that clearly showed a change in the size of the reflected images, just as had been observed since the late nineteenth century.
Bates adhered to a different explanation of accommodation that had already been generally disregarded by the medical community of his time. Bates' model had the muscles surrounding the eyeball controlling its focus. In addition to their known function of turning the eye, Bates maintained, they also affect its shape, elongating the eyeball to focus at the near-point or shortening it to focus at a distance. Commenting on this hypothesis in an interview with WebMD, ophthalmologist Richard E. Bensinger stated "When we put drops in the eye to dilate the pupil, they paralyze the focusing muscles. The evidence of the anatomical fallacy is that you can't focus, but your eye can move up and down, left and right. The notion that external muscles affect focusing is totally wrong." Science author John Grant writes that many animals, such as fishes, accommodate by elongation of the eyeball, "it's just that humans aren't one of those animals."
Laboratory tests have shown that the human eyeball is far too rigid to spontaneously change shape to a degree that would be necessary to accomplish what Bates described. Exceedingly small changes in axial length of the eyeball (18.6â"19.2 micrometres) are caused by the action of the ciliary muscle during accommodation. However, these changes are far too small to account for the necessary changes in focus, producing changes of only â'0.036 dioptres.
Causes of sight problems
Medical professionals characterize refractive errors such as nearsightedness, farsightedness, astigmatism, and presbyopia (the age-related blurring of near-point vision) as consequences of the eye's shape and other basic anatomy, which there is no evidence that any exercise can alter. Bates, however, believed that these conditions are caused by tension of the muscles surrounding the eyeball, which he believed prevents the eyeball from sufficiently changing shape (per his explanation of accommodation) when gaze is shifted nearer or farther. Bates characterized this supposed muscular tension as the consequence of a "mental strain" to see, the relief of which he claimed would instantly improve sight. He also linked disturbances in the circulation of blood, which he said is "very largely influenced by thought", not only to refractive errors but also to double vision, crossed-eye, lazy eye, and to more serious eye conditions such as cataracts and glaucoma. His therapies were based on t hese assumptions.
Bates felt that corrective lenses, which he characterized as "eye crutches", are an impediment to curing poor vision. In his view, "strain" would increase as the eyes adjust to the correction in front of them. He thus recommended that glasses be discarded by anyone applying his method.
Treatments
In his writings, Bates discussed several techniques that he claimed helped patients to improve their sight. He wrote "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 disassociate this "strain" from seeing and thereby achieve "central fixation", or seeing what is in the central point of vision without staring. He asserted that "all errors of refraction and all functional disturbances of the eye disappear when it sees by central fixation" and that other conditions were often relieved as well.
Palming
Bates suggested closing the eyes for minutes at a time to help bring about relaxation. He asserted that the relaxation could be deepened in most cases by "palming", or covering the closed eyes with the palms of the hands, without putting pressure on the eyeballs. If the covered eyes did not strain, 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 some of his patients experienced "illusions of lights and colors" sometimes amounting to "kaleidoscopic appearances" as they "palmed", occurrences he attributed to his ubiquitous "strain" and that he claimed disappeared when one truly relaxed. This phenomenon, however, was almost certainly caused by Eigengrau or "dark light". In fact, even in conditions of perfect darkness, as inside a cave, neurons at every level of the visual system produce random background activity that is interpreted by the b rain as patterns of light and color.
Visualization
Bates placed importance on mental images, as he felt relaxation was the key to clarity of imagination as well as of actual sight. He claimed that one's poise could be gauged by the visual memory of black; that the darker it appeared in the mind, and the smaller the area of black that could be imagined, the more relaxed one was at the moment. He recommended that patients think of the top letter from an eye chart and then visualize progressively smaller black letters, and eventually a period or comma. But he emphasized his view that the clear visual memory of black "cannot be attained by any sort of effort", stating 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.
Movement
He thought that the manner of eye movement affected the sight. He suggested "shifting", or moving the eyes back and forth to get an illusion of objects "swinging" in the opposite direction. He believed that the smaller the area over which the "swing" was experienced, the greater was the benefit to sight. He also indicated that it was usually helpful to close the eyes and imagine something "swinging". By alternating actual and mental shifting over an image, Bates wrote, many patients were quickly able to shorten the "shift" to a point where they could "conceive and swing a letter the size of a period in a newspaper". One who mastered this would attain the "universal swing", Bates believed.
Perhaps finding Bates' concepts of "shifting" and "swinging" too complicated, some proponents of vision improvement, such as Bernarr Macfadden, suggested simply moving the eyes up and down, from side to side, and shifting one's gaze between a near-point and a far-point.
Sunning
Bates believed that the eyes were benefited by exposure to sunlight. He stated 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 purportedly improving after sungazing â" this is at variance with the well-known risk of eye damage that can result from direct sunlight observation.
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 it could be worked up to. He acknowledged that looking at the sun could have ill effects, but characterized them as being "always temporary" and in fact the effects of strain in response to sunlight. He wrote that he had cured people who believed that the sun had caused them permanent eye damage. In his magazine, Bates later suggested exposing only the white part of the eyeball to direct sunlight, and only for seconds at a time, after allowing the sun to shine on closed eyelids for a longer period.
Posthumous publications of Bates' book omitted mention of the supposed benefits from direct sunlight shining on open eyes.
Results and criticism
Bates' techniques have never been scientifically established to improve eyesight. Several of Bates' techniques, including "sunning", "swinging", and "palming", were combined with healthy changes to diet and exercise in a 1983 randomized controlled trial of myopic children in India. After 6 months, the experimental groups "did not show any statistically significant difference in refractive status", though the children in the treatment group "subjectively ⦠felt relieved of eye strain and other symptoms".
In 1967 the British Medical Journal observed that "Bates [â¦] advocated prolonged sun-gazing as the treatment of myopia, with disastrous results."
The philosopher Frank J. Leavitt has argued that the method Bates described would be difficult to test scientifically due to his emphasis on relaxation and visualization. Leavitt asked "How can we tell whether someone has relaxed or imagined something, or just thinks that he or she has imagined it?" In regards to the possibility of a placebo trial, Leavitt commented "I cannot conceive of how we could put someone in a situation where he thinks he has imagined something while we know that he has not."
After Bates
After Bates died in 1931, his methods of treatment were continued by his widow Emily and other associates, some of whom incorporated exercises and dietary recommendations. Most subsequent proponents did not stand by Bates' explanation of how the eye focuses mechanically, but nonetheless maintained that relieving a habitual "strain" was the key to improving sight.
Margaret Darst Corbett
Margaret Darst Corbett first met Bates when she consulted him about her husband's eyesight. She became his pupil, and eventually taught his method at her School of Eye Education in Los Angeles. She was of the stated belief that "the optic nerve is really part of the brain, and vision is nine-tenths mental and one-tenth only physical."
In late 1940, Corbett and her assistant were charged with violations of the Medical Practice Act of California for treating eyes without a licence. At the trial, many of her students testified on her behalf, describing in detail how she had enabled them to discard their glasses. One witness testified that he had been almost blind from cataracts, but that, after working with Corbett, his vision had improved to such an extent that for the first time he could read for eight hours at a stretch without glasses. Corbett explained in court that she was practicing neither optometry nor ophthalmology and represented herself not as a doctor but only as an "instructor of eye training". Describing her method she said "We turn vision on by teaching the eyes to shift. We want the sense of motion to relieve staring, to end the fixed look. We use light to relax the eyes and to accustom them to the sun."
The trial attracted widespread interest, as did the "not guilty" verdict. The case spurred a bill in the Californian State Legislature that would have then made such vision education illegal without an optometric or medical licence. After a lively campaign in the media, the bill was rejected.
Aldous Huxley
Perhaps the most famous proponent of the Bates method was the British writer Aldous Huxley. At the age of sixteen Huxley had an attack of keratitis, which, after an 18-month period of near-blindness, left him with one eye just capable of light perception and the other with an unaided Snellen fraction of 10/200. This was mainly due to opacities in both corneas, complicated by hyperopia and astigmatism. He was able to read only if he wore thick glasses and dilated his better pupil with atropine, to allow that eye to see around an opacity in the center of the cornea.
In 1939, at the age of 45 and with eyesight that continued to deteriorate, he happened to hear of the Bates method and sought the help of Margaret Corbett, who gave him regular lessons. Three years later he wrote The Art of Seeing, in which he related: "Within a couple of months I was reading without spectacles and, what was better still, without strain and fatigue.... At the present time, my vision, though very far from normal, is about twice as good as it used to be when I wore spectacles." Describing the process, Huxley wrote that "Vision is not won by making an effort to get it: it comes to those who have learned to put their minds and eyes into a state of alert passivity, of dynamic relaxation." He expressed indifference regarding the veracity of Bates' explanation of how the eye focuses, stating that "my concern is not with the anatomical mechanism of accommodation, but with the art of seeing."
His case generated wide publicity as well as scrutiny. Ophthalmologist Walter B. Lancaster, for example, suggested in 1944 that Huxley had "learned how to use what he has to better advantage" by training the "cerebral part of seeing", rather than actually improving the quality of the image on the retina.
In 1952, ten years after writing The Art of Seeing, Huxley spoke at a Hollywood banquet, wearing no glasses and, according to Bennett Cerf, apparently reading his paper from the lectern without difficulty. In Cerf's words:
Then suddenly he falteredâ"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.
In response to this, Huxley wrote "I often do use magnifying glasses where conditions of light are bad, and have never claimed to be able to read except under very good conditions." This underscored that he had not regained anything close to normal vision, and in fact never claimed that he had.
Modern variants
"Natural vision correction" or "natural vision improvement" continues to be marketed by practitioners offering individual instruction, many of who have no medical or optometric credentials. Most base their approach in the Bates method, though some also integrate vision therapy techniques. There are also many self-help books and programs, which have not been subjected to randomized controlled trials, aimed at improving eyesight naturally. Purveyors of such approaches argue that they lack the funds to formally test them.
The heavily advertised "See Clearly Method" (of which sales were halted by a court order in November 2006, in response to what were found to be dishonest marketing practices) included "palming" and "light therapy", both adapted from Bates. The creators of the program, however, emphasized that they did not endorse Bates' approach overall.
In his 1992 book The Bates Method, A Complete Guide to Improving Eyesightâ"Naturally, "Bates method teacher" Peter Mansfield was very critical of eye care professionals for prescribing corrective lenses, recommending most of Bates' techniques to improve vision. The book included accounts of twelve "real cases", but did not report any information about refractive error.
Czech native John Slavicek claims to have created an "eye cure" that improves eyesight in three days, borrowing from ancient yogic eye exercises, visualizations from the Seth Material, and the Bates method. Although he has testimonials from his neighbor and others, several of his students indicate that he has greatly exaggerated their cases. Slavicek's self-published manual, Yoga for the Eyes, was rejected by an ophthalmologist who evaluated it, and evinced no interest from the World Health Organization and St. Erik's Eye Foundation in Sweden as he had not conducted double-blind tests.
Anecdotal support
In support of the effectiveness of the Bates method, proponents point to the many accounts of people allegedly having improved their eyesight by applying it. While these anecdotes may be told and passed on in good faith, several potential explanations exist for the phenomena reported other than a genuine reversal of a refractive error due to the techniques practiced:
- Some cases of nearsightedness are recognized as due to a transient spasm of the ciliary muscle, rather than a misshapen eyeball. These are classed as pseudomyopia, of which spontaneous reversal may account for some reports of improvement.
- Research has confirmed that when nearsighted subjects remove their corrective lenses, over time there is a limited improvement (termed "blur adaptation") in their unaided visual resolution, even though refraction indicates no corresponding change in refractive error. This is believed to occur due to adjustments made in the visual system. One who has been practicing Bates' techniques and notices such improvement may not realize that simply leaving the glasses off would have had the same effect, which may be especially pronounced if the prescription was too strong to begin with.
- Visual acuity is affected by the size of the pupil. When it constricts (such as in response to an increase in light), the quality of focus will improve significantly, at the cost of a reduced ability to see in dim light. This is known as the "pinhole effect". This concept is also used in photography when changing the aperture size.
- Some eye defects may naturally change for the better with age or in cycles (ophthalmologist Stewart Duke-Elder suggested that this is what happened with Aldous Huxley). A cataract when first setting in sometimes results in much improved eyesight for a short time. One who happens to have been practicing the Bates method will likely credit it for any improvement experienced regardless of the actual cause.
- Some studies have suggested that a learned ability to interpret blurred images may account for perceived improvements in eyesight. Ophthalmologist Walter B. Lancaster had this to say: "Since seeing is only partly a matter of the image on the retina and the sensation it produces, but is in still larger part a matter of the cerebral processes of synthesis, in which memories play a principal role, it follows that by repetition, by practice, by exercises, one builds up a substratum of memories useful for the interpretation of sensations and facilitates the syntheses which are the major part of seeing." Lancaster faulted ophthalmologists in general for neglecting the role of the brain in the process of seeing, "leaving to irregular, half-trained workers the cultivation of that field".
- A 1952 study involving 100 subjects claiming to experience "flashes" of clear vision, in which eyesight momentarily becomes much sharper, found only one subject who "demonstrated unusually good transient acuity (a flash) but she was unable to maintain it or repeat it for measurement of refraction" and concluded that "'flashers' (those who can obtain remarkably large transient increases in visual acuity) are uncommon". A 2004 study proposed that such flashes may be caused by "negative accommodation" (i.e. an active flattening of the lens by the ciliary muscles).
- A 1982 study of subjects who underwent computer-based visual training concluded that any perceived resulting improvement in visual acuity is best explained as a contact lens-like effect of moisture on the eye, based on increased tear action exhibited by 15 out of 17 subjects who experienced such improvement.
- A 2003 study of claims that "positive suggestion (e.g., using hypnosis) can significantly improve visual acuity" found that "neither suggestion nor hypnotic phenomena are likely to significantly improve myopic vision".
General research
In 2004 the American Academy of Ophthalmology (AAO) published a review of various research regarding "visual training", which consisted of "eye exercises, muscle relaxation techniques, biofeedback, eye patches, or eye massages", "alone or in combinations". No evidence was found that such techniques could objectively benefit eyesight, though some studies noted changes, both positive and negative, in the visual acuity of nearsighted subjects as measured by a Snellen chart. In some cases noted improvements were maintained at subsequent follow-ups. However, these results were not seen as actual reversals of nearsightedness, and were attributed instead to factors such as "improvements in interpreting blurred images, changes in mood or motivation, creation of an artificial contact lens by tear film changes, or a pinhole effect from miosis of the pupil."
In 2005 the Ophthalmology Department of New Zealand's Christchurch Hospital published a review of forty-three studies regarding the use of eye exercises. They found that "As yet there is no clear scientific evidence published in the mainstream literature supporting the use of eye exercises" to improve visual acuity, and concluded that "their use therefore remains controversial."
General criticisms
Dead-end
A frequent criticism of the Bates method is that it has remained relatively obscure, which is seen as proof that it is not truly effective. Writer Alan M. MacRobert concluded in a 1979 article that the "most telling argument against the Bates system" and other alternative therapies was that they "bore no fruit". In regards to the Bates method, he reasoned that "If palming, shifting, and swinging could really cure poor eyesight, glasses would be as obsolete by now as horse-drawn carriages."
Corrective lenses and safety
Discarding one's corrective lenses, as Bates recommended, or wearing lenses weaker than one's prescribed correction, as some Bates method advocates suggest, poses a potential safety hazard in certain situations, especially when one is operating a motor vehicle. James Randi related that his father, shortly after discarding glasses on the advice of Bates' book, wrecked his car. Bates method teachers often caution that when driving, one should wear the correction legally required.
Avoidance of conventional treatment
One of the greatest potential dangers of faith in the Bates method is that a believer may be disinclined to seek medical advice regarding what could be a sight-threatening condition requiring prompt treatment, such as glaucoma. Also, children with vision problems may require early attention by a professional in order to successfully prevent lazy eye. Such treatment may include exercises, but which are different from those associated with the Bates method, and parents who subscribe to Bates' ideas may delay seeking conventional care until it is too late. It may further be necessary for a child at risk of developing lazy eye to wear the proper correction.
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