Bates Method

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The Bates Method is a controversial system of practices that are claimed to improve sight and reverse ocular disorders to normal by eliminating "mental strain" and restoring the "natural habits" of seeing. It is the backbone of the natural vision improvement movement, and was first described in 1920 by ophthalmologist William Horatio Bates in a book entitled Perfect Sight Without Glasses, then subsequently in his monthly magazine entitled Better Eyesight.

The Bates Method is rejected by mainstream opthalmology. Still many people claim to have been helped by the method.

Bates writings fall under two main headings; his theory of accommodation, and his recommended practices for improving vision. The truth of his theory is a separate question from the efficacy of his practices. His theory that the eye does not focus by changing the power of the lens, but rather by elongating the eyeball, through use of the extraocular oblique muscles, is contradicted by mainstream ophthalmology. Supporters believe that even if his theory is wrong, his methods do work.

According to Bates, his method is applicable for myopia, hyperopia, astigmatism, presbyopia, strabismus, amblyopia, nystagmus, and numerous other conditions affecting the eye Template:Fact.

Bates' theories

Accommodation by extraocular muscle squeezing

Accommodation is the process by which the eye increases optical power to maintain focus on the retina. So when the eyes change from viewing a distant object to a near object accommodation is taking place.

Bates rejected the orthodox view that accommodation was brought about by the action of the ciliary muscle on the eye's crystalline lens [1], and claimed that focus was maintained by varying elongation of the eyeball caused by the extraocular muscles. Although subsequently contradicted by experiments using modern equipment, Bates claimed that the lens played no part in accommodation and reported that the extraocular muscles, and in particular the oblique muscles, squeeze the eyeball to obtain focus by elongation. Excessive tension of the recti muscles may also make, according to Bates, the eyeball too short (leading to hyperopia, and excessive tension of the oblique and recti muscles makes the eye astigmatic.

Close work

Advocates of the Bates Method claim that viewing books, computer monitors, and other near-vision activities are harmless, as long as a person maintains the right vision habits. They claim that eyeglasses are an unnecessary crutch. Bates advocates also claim that the Tibetan eye chart has long been used for the purpose of helping to keep eye muscles toned, and that acupressure techniques can be used to improve vision and increase circulation to the eyes.

Eyeglasses

Bates wrote: "At their best it cannot be maintained that glasses are anything more than a very unsatisfactory substitute for normal vision" [2]. He claimed that eyeglasses injured the eyes and did not restore normal vision [3]. The refractive condition of the eye, he maintained, is constantly changing, from day to day and from hour to hour, and so the prescribing of corrective lenses can only ever be right at the time they are fitted, after which they force the eye to adjust to them. Ophthalmologists acknowledge some truth to this phenomenon, referring to 'hysteresis', an observed phenomenon of the eye taking time to restore its range after extended use at one distanceTemplate:Fact. They also observe that hysteresis is greater in myopic subjects, who they find cannot adjust their focus so quickly as normal subjectsTemplate:Fact. They would not regard this as 'injuring the eye' to any significant extent though.

Bates cited many disadvantages to eyeglasses, maintaining that they adversely affected color perception, contracted the field of vision, and caused dizziness and headaches when the wearer viewed objects off-axis [4]. Although some of these symptoms are still experienced from time-to-time by some of today's eyeglasses wearers, improvements in modern lenses have generally improved vision quality, such as anti-reflective coatings that have improved image contrast by reduced scattering

Mental Straining alters the eye's shape

Bates claimed that straining to see at the near-point led to shortening of the eyeball resulting in hypermetropia (farsightedness), and that straining to see at the far-point led to lengthening of the eyeball leading to myopia (nearsightedness). At first this seems back-to-front, but by straining to see at the near-point Bates did not mean habitual close-work, or even tensing of the muscles, he meant 'straining' in a mental sense. He makes this clear in his chapter entitled 'strain' where he says, "if the muscles respond to the minds desire, they do so without strain". Some have assumed that Bates saw prolonged tension in the extraocular muscles as directly causing eyeball deformation [5]. His 'mental strain' is quite unconnected with muscle tension, and he sees the maladjustment as being in the brain, not the eyeTemplate:Fact.

Bates concluded that myopia was related to apprehension, or what some may call "anxiety". He reportedly felt that good vision was nature's way, and that any other way was a strained way of seeing. Bates believed that it was impossible to consciously relieve the eyes of this tensing, and instead developed his method as a means of effecting subconscious relaxation.

Light is the life-blood of the eyes

Bates believed exposure to light was good for the eyes. Modern research indicates that those factors, like a blurred image, which seem able to alter the axial length of the eyeball, are more effective in conditions of high brightness and/or contrast.

Bates' relaxation techniques

Bates claimed to have discovered that people with abnormal vision use their eyes differently than people with normal vision, and then created a system designed to help people to relearn the right vision habits. Advocates of the Bates Method claim that these vision habits are inseparably connected to normal vision. They assert that the Bates Method is a natural method that improves movement, relaxation, and circulation of the whole visual system. It is important to realise that Bates' 'exercises' are not true exercises aimed at muscle strengthening. They are mostly, like many yoga 'exercises', aimed at procuring a state of relaxation.

Relaxation is at the core of the Bates Method, involving a set of practices which Bates advocates term "exercises in relaxation" and "movement exercises" [6]. They emphasise that the term "exercise" is used in the same sense as "memory exercise" and does not imply muscle strengthening.

Swinging involves deliberate movements of the body with relaxed awareness of vision.

Palming or cupping is one technique that advocates claim achieves relaxation of the mind and the eyes. Palming requires a person to gently cup the palms of the hands over the closed eyelids, and attempt to see "perfect black" in order give the mind and the visual system as much rest as possible. Then the person sits for five to fifteen minutes (or as long he or she wants) breathing deeply and easy with a good posture.

Sunlight exposure involves looking at the sun through closed eyelids. Bates considered light to be the 'lifeblood' of healthy eyes. The practice of opening the eyes briefly while looking at the sun is claimed to be effective by some supporters but this is one aspect of the Bates method that must be considered 'potentially dangerous.

Central fixation was considered very important by Bates. Recognizing that only a very small part of the retina is capable of the highest resolution, he claimed that many people, when reading, allow the central fixation needed to maintain a sharp image to wander, so that they are attempting to focus using a low resolution part of the retina. He emphasized that good fixation is about relaxing and allowing the eyes to change gaze rapidly and naturally, rather than straining to fixate, which results in staring. Staring is the result of tension, according to Bates, and very bad.

Aldous Huxley - famous advocate of the Bates method

The British writer Aldous Huxley (author of Brave New World) was one such advocate. Huxley claimed achieving successful results in his book entitled The Art of Seeing. Huxley was among the students of Margaret Corbett, who trained with Dr. Bates in 1930 and later authored Help Yourself to Better Sight.

However, while Huxley undoubtedly believed his vision had improved, Bennett Cerf thought otherwise. In 1952 Cerf was present when Huxley spoke at a Hollywood banquet, wearing no glasses and apparently reading his paper from the lectern without difficulty:

Then suddently he faltered—and the truth became obvious. He wasn't reading his address—he had learned it by heart. To refresh his memory he brought it closer and closer to his eyes. When it was only an inch 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.Template:Ref

Safety

Advocates believe the Bates Method to be safe. Critics concede that most of the Bates techniques are harmless, apart from the possibility that faith in the Bates system could deter people with eye conditions requiring prompt care from seeking conventional treatment. (One of his original exercises, however, involved looking directly at the sun, which in some situations may be dangerous; a 1940 revision of his book modified this by suggesting that the sun shine on closed eyes.)

Criticisms of the Bates Method

Theory of accommodation/focusing

Critics of the Bates Method reject the theory that human eyes accommodate, or focus, due to elongation of the eyeball caused by “squeezing” of the extraocular muscles, as has been claimed to happen in some animals. Critics of the Bates Method instead support the mainstream theory set forth by Hermann von Helmholtz that human eyes accommodate, or focus, due to the actions of the ciliary muscle (an intraocular muscle) and zonules changing the shape of the crystalline lens. To support this theory, critics of the Bates Method point to the action of various cycloplegic agents which temporarily paralyze accommodation by relaxing the ciliary muscle but leave the extraocular muscles, which control eye movements, unaffected. They also note that modern equipment, not available to Bates, has made possible the observation of the eye in great detail; such observations show the lens changing shape when the eye accommodates. [7]

Theory regarding the pathogenesis of refractive errors

Critics of the Bates Method contend that if the cause of myopia is continuous tensing of the muscles, either ciliary or extraocular, the Bates Method theory is that it should be possible to cure (or noticeably improve) it by causing intentional relaxation of the muscles; a process most commonly done using injections or topical administration of atropine. The mainstream consensus on this, however, is that no significant improvement of the vision is obtained when muscles are relaxed in this manner.

Efficacy

The vast majority of optometrists and ophthalmologists do not recommend the Bates Method. Martin Gardner, in Fads and Fallacies in the Name of Science, characterized Bates' book as "a fantastic compendium of wildly exaggerated case records, unwarranted inferences and anatomical ignorance." He suggested that the Bates method may however work, to a limited degree, by increasing the trainee's ability to interpret and extract information from blurred images.

Other eye-exercise methods

In recent years, the growing interest in alternative medicine has led to an increase in the popularity of the Bates Method and other methods claiming success via visual training through eye exercises. One particularly controversial area is the efficacy of eye exercises in the treatment of myopia (near-sightedness) and whether the use of eyeglasses makes myopia progressively worse.

Several points-of-view exist about the use of eye exercises to treat vision problems:

Traditional mainstream ophthalmologists and optometrists use eye exercises to treat a limited range of problems, particularly problems involving muscular imbalances and problems with coordination of eye movement between the two eyes. (See orthoptics.)
Functional optometrists and optometric vision therapists are licensed, credentialed doctors of optometry, who specialize in treatment that involves eye exercises. They hold that such exercises are useful in improving a wide range of visual conditions, including focusing problems. The methods used are said to be backed by clinical studies and publications in peer-reviewed journals. (See vision therapy.)
The Bates method differs from other health systems that use eye exercises in a way that can be categorized as alternative medicine. Like homeopathic medicine, the treatments used and the explanations of how they are said to work are rejected by mainstream medicine, despite personal testimony by people who claim to have been helped by such methods.

Pathogenesis and control of myopia: the modern "debate"

Although not alone in his endeavors, Bates is commonly recognized as one of the first in the modern era to attempt to prevent, arrest, or reverse myopia and other refractive errors. His techniques (designed to eliminate “mental strain”) have been largely rejected by mainstream ophthalmology as ineffective, but certain pharmaceuticals, contact lenses, and surgeries have achieved varying degrees of success, as have vision therapy and plus lenses in the treatment of pseudomyopia.

In direct contrast to research over the past ten to twenty years which has implicated heavy amounts of near-work as a contributing factor to the development of myopia [8] [9], Bates emphasized that that near-work and “overuse of the eyes” were not necessary to cause myopia, and claimed that he “made many dogs myopic by inducing them to strain to see a distance object”. To Bates, refractive errors were due to a “loss of mental control” brought about by “strain”, specifically “strain of the mind”. He wrote: “The remedy is not to avoid either near work or distant vision, but to get rid of the mental strain which underlies the imperfect functioning of the eye at both points.”

Despite considerable evidence that blurred images appear to trigger changes in the axial length of the eyeball through a complex feedback mechanism, Bates advocates hold the original hypothesis that “mental strain” is ultimately responsible for the development of refractive error through extraocular muscle squeezing of the globe. They contend that various eye exercises could affect a person’s refractive error by altering the structure of the eyeball; however, there is no modern research that directly supports these claims.

More and more research is supporting the idea that prolongued retinal defocus probably plays a part, along with herditary predisposition, in the development of myopia, and there have been recent suggestions that relieving this strain by the use of reading glasses with positive lenses might stave off the development of myopia, while corrective (negative) lenses for far vision might hasten its development.

An area of great relevance concerns the mechanism by which our brain focuses our eyes and converges our binocular vision for near-sight. Basic optical principles suggest that there is no way in which the eye can tell whether a blurred image is being brought to focus in front of or behind the retina, and hence which way to change focus. This is supported by the fact that modern digital cameras with passive autofocus use a trial and error approach, shifting focus first one way and then the other while attempting to maximise contrast in areas of fine detail. If the brain uses this trial and error method, then it must remember what stage it is at and decide when to stop, a difficult task for a neural network, and one that does not always work reliably or quickly in cameras.

This suggests that the brain might use other cues like binocular convergence, or perceived object size and distance to direct focussing, perhaps with trial and error for fine trimming. In principle, convergence on near objects to avoid double vision need not be trial and error, but can use negative feedback from the two apparent image positions to adjust the extraocular muscles rapidly for coincident images. Convergence could therefore be the driver for accommodation. The whole issue of convergence and accommodation is discussed in detail in the 'Myopia Manual' by Klaus Schmid [10], which attempts to review the entire published literature. In section 3.4 of the Myopia Manual, Phoria is described as a defect in which convergence and accommodation do not track together properly. The manual refers to evidence that the progression of myopia is in fact linked with the degree of esphoria, and that the development of myopia is linked with pre-existing esophoria. The manual goes into more technical details involving the AC/A and CA/C ratios which describe how accommodation and convergence track each other. A recent study in Malaysia also concluded that phoria might be an important factor in myopia development [11].

If such cues are indeed used, then it follows that the wearing of glasses is likely to confuse the brain, and weaken its acquired algorithms, by changing the relationship between convergence and apparent focus distance, requiring the wearer to develop two or more separate programs in the brain for acquiring focus with and without glasses. The Myopia manual goes on to describe the use of prisms for correcting phoria, indicating that prisms added to prescription lenses might slow the progression of myopia.

Phoria could be part of the reason myopia progresses in young people wearing corrective glasses. It could also be relevant when presbyopia sets in and we start to focus through multiple lenses or varifocals.

References

Template:Note Gardner, Martin (1957), Fads and Fallacies in the Name of Science. Reprint: Courier Dover, ISBN 0486203948. (p. 241: quotes Bennett Cerf re Huxley's vision in 1952)

See also

External links

Vision Improvement Self-Help Books

Books about the classic Bates Method. These books are close related to Bates initial theory and instruction. Some however also talk about fitness and nutrients. Books about the Second generation Bates are written by authors who worked as vision improvement consultants. They never knew Bates personally but developed their own approach using the Bates Method as a starting point. See :

http://www.i-see.org/vision_books.html

Free books and articles by Dr. W. H. Bates

Supportive of the Bates Method

Critical of the Bates Method

he:שיטת בייטס nl:Batesmethode

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Categories: Manipulative therapy | Alternative medicine | Ophthalmology | Quackery

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