Definitions

negative accommodation

Bates method

The Bates method for "better eyesight" was developed by eye-care physician William Horatio Bates, M.D. (1860–1931) with the goal of undoing what he described as "strained" vision habits. Bates detailed 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 Magazine, published from 1919 to 1930. The Bates method is not considered by optometrists and ophthalmologists to be an effective form of vision correction.

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 techniques have not been shown to objectively improve eyesight, and his main physiological proposition, that the extraocular oblique muscles adjust the shape of the eyeball to maintain its focus, was rejected by ophthalmology and optometry of his day, and is still rejected today. In Fads and Fallacies in the Name of Science, mathematical journalist 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, due to the eyes adjusting to seeing without glasses when they are put aside.

Adherence to Bates' ideas is not entirely without risk, as it is possible that those who attempt to follow his suggestions might overexpose their eyes to sunlight or neglect conventional eye-care when it is needed. Additionally if they stop wearing glasses, as Bates recommended, this might compromise safety or performance in contexts where clear vision is essential, such as driving.

Bates' ideas

Central to most of Bates' ideas regarding eyesight was his thesis that "mental strain" caused poor vision, an assumption on which his therapies were based.

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 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 such as atropine can temporarily prevent accommodation by paralyzing the ciliary muscle. Bates acknowledged that this stopped accommodation in "about nine cases out of ten", but argued that the "tenth cases" in which applying atropine to the ciliary muscle failed to stop accommodation constituted strong evidence that that muscle is not actually responsible for accommodation. However, it is recognized that a single dose of atropine is not always enough to induce paralysis.

To boost his assertion that the extraocular muscles are responsible for accommodation, Bates cited the apparent ability of some aphakics to accommodate. These instances, however, are extremely rare, and as such are best considered exceptions to the rule; moreover, examination of such cases has found no change in the refractive power of the eye.

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.

Causes of sight problems

Bates disregarded the medical explanation that the eyeball is entirely structural in shape, and thus refractive errors are static conditions. Instead, he maintained that the extraocular muscles not only turn the eyeball but also affect its shape, and thus the refractive state of the eye is variable.

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 proposition that "mental strain" causes sight problems is crucial to Bates' work, but is perhaps the most vague aspect of his writings. "strain#Verb" 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, as their eye-brain pathways are still forming, and this process is dependent on visual images. In some situations, it is necessary to correct a child's refractive error promptly in order to prevent the development of amblyopia.

Regarding contact lenses, some Bates method advocates point out that unlike glasses, contacts are not normally removed during moments when they are not needed, and thus characterize contacts as an even larger impediment to improvement than glasses.

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 this "strain" from seeing and thereby achieve "central fixation", or seeing best at the central point of vision. He claimed that "all errors of refraction and all functional disturbances of the eye disappear when it sees by central fixation" and that other conditions are often relieved as well. However, 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 characterize refractive errors as "static, anatomic conditions" caused by "structural defect of the eyeball", which as such cannot be affected by Bates' techniques or any variations thereof.

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 this "strain" resurfaced. While such "clear flashes" do actually occur, observation of subjects attaining them has found using retinoscopy that they are not the result of any change in refractive power. A 1982 study determined that these flashes are 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 obtained them.

Palming

Bates 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 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 which he attributed to his ubiquitous "strain" and which he claimed disappeared when one truly relaxed. This phenomena, however, was almost certainly caused by eigengrau or "dark light". In fact, it is impossible to see entirely "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 color and light in the visual field. Similar hallucinations can be invoked by visual deprivation using a Ganzfeld.

Memory and imagination

Bates reasoned that any given object could be seen as clearly as it was visualized, until the "strain" increased, as he felt relaxation was the key to clarity of imagination as well as of actual sight. 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 his view 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 the manner of eye movement is key to how well one sees. 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 shorter the area over which the "swing" is experienced, the greater the benefit to sight. He also indicated that it is usually helpful to close the eyes and imagine something swinging. By alternating actual and mental shifting over an image, Bates reported, 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 masters this will attain the "universal swing", Bates believed.

In his Better Eyesight magazine, Bates set forth several techniques designed to help realize and then shorten the "swing". One such method 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.

The terms "shift" and "swing" are not used in this fashion outside of a Bates context. Bates provided no evidence of any correlation between visual acuity and eye movement, beyond his own clinical experience, which is effectively anecdotal.

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, as direct sunlight exposure can cause damage to the retina known as solar retinopathy, which has been observed in individuals who have watched eclipses. Figures in Chapter 17 of Bates' Perfect Sight Without Glasses show multiple individuals sungazing 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. However, Bates did temper his suggestions regarding this activity in later editions of his magazine, recommending instead that direct sunlight be allowed to shine on closed eyelids. He also clarified that he regarded the benefit as being in the solar light rays rather than the heat rays, and thus suggested "sunning" in the early morning, moving the head from side to side.

After Bates

After Bates died in 1931, his methods of treatment were continued by his widow Emily and other associates, some of who incorporated exercises and dietary recommendations.

Margaret Darst Corbett

Margaret Darst Corbett first met Dr. Bates when she consulted him about her husband’s eyesight. She became his pupil, and eventually taught his method at her Los Angeles “School of Eye Education”. 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 Mrs. 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 witnesses testified on her behalf. They described in detail how she had improved their sight and had enabled them to discard their glasses. One witness testified that he had been almost blind from cataracts, but that, after receiving treatment, his vision had improved to such an extent that for the first time he could read for eight hours at a stretch without glasses. Mrs. Corbett explained in court that she was practising 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 which would have then made such vision education illegal without an optometric or medical licence. After a lively campaign in the media, the bill was defeated.

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 only if he dilated his better pupil with atropine and used glasses.

In 1939, at the age of 45 and with eyesight which 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".

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, 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 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."

In response to this, Huxley pointed out that he had "never claimed to be able to read except under very good conditions", and explained that he often did "use magnifying glasses where conditions of light are bad". He had previously written 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.”

Modern variants

Today, many "self-help" books and "programs" exist claiming to improve eyesight "naturally" by various means, most having some basis in the Bates method. The heavily advertised "See Clearly Method" (which in November 2006 was shut down by a court order 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. Likewise, some Bates method proponents have distanced themselves from the See Clearly Method.

Ophthalmological research

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". The review found "level I evidence" (meaning that it was taken from randomized controlled trials) "that visual training for control of accommodation has no effect on myopia." While some of the reviewed studies did report improvements in the visual acuity of myopes, these were seen as subjective rather than objective gains, perhaps resulting from a learned ability to interpret blurred images, or other factors detailed below. Furthermore, no evidence was found that visual training had any effect on hyperopia or astigmatism, on the progression of myopia, or on vision loss due to eye diseases.

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."

Claimed success

As their strongest evidence for 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 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 myopia are recognized as due to a transient spasm of the ciliary muscle, rather than a misshapen eyeball. These are classed as pseudomyopia, and sometimes can benefit from relaxation.
  • As noted above, the "clear flashes" often spoken of by Bates enthusiasts have been determined experimentally to most likely be a contact lens-like effect of moisture on the eye.
  • Recent research has confirmed that when subjects with myopia remove their refractive correction, after a while blur adaptation develops to produce an improvement in their unaided visual resolution, even though no significant change in refractive error (measured using autorefraction) is found. 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.
  • Some eye defects may naturally change for the better with age or in cycles. As well, 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 of course credit it for any such improvements, though they are unrelated.

The other factor which applies here is the potential for selection bias, the effect whereby spurious relationships can appear to exist due to selective reporting. In this case, many people have tried the Bates method. For some, their eyesight may have seemingly improved; for some no noticeable change occurred; in some cases, perhaps, their eyesight has deteriorated. If only the first of these groups publicize what has happened, and the other two groups keep silent or are ignored, it will appear that the Bates method has been very effective, whereas in actuality it may not have been.

General criticisms

Dead-end

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." It has been pointed out, however, that due to Bates' emphasis on relaxation and visualization, application of the method would depend heavily on each individual, as with martial arts and yoga. That people still wear glasses therefore does not in itself discredit the Bates method.

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 treatment by a professional in order to successfully prevent or reverse double vision or lazy eye, and parents who subscribe to Bates' ideas may delay seeking conventional care until it is too late. Bates method teachers sometimes 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

References

Further reading

External links

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