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Improve your Eyesight
A Guide to the Bates Method for Better Eyesight without Glasses
By Jonathan Barnes
Souvenir PressCopyright © 1987 Jonathan Barnes
All rights reserved.
You are no doubt already wondering: "What is the Bates method, and if it is so marvellous why haven't I heard about it before?"
Briefly, the method is a way of re-educating the eyesight. Errors of refraction (that is, of focusing) are regarded as temporary abnormalities which, when exposed to the healing and self-regulatory powers of the body, can be reduced in severity or eliminated altogether.
As to why you haven't heard about it before, there are several reasons. The first and most important is the attitude of the medical profession. In our culture we have come to rely too heavily on the theoretical approach to medicine. No cure can be truly acceptable unless and until there is a theory to explain it. The theory accounting for refractive error is the work of the German scientist Hermann von Helmholtz (1821–94), whose contribution to the study of the nervous system still dominates modern thinking. Helmholtz's theory states that the eye accommodates (changes focus for far and near objects) by means of changes in the shape of the lens. If the lens or its muscle system is faulty, or if the eyeball is congenitally malformed, then refractive errors will arise. Although there is even now some controversy over the exact mechanism by which the lens changes its shape, orthodox science has never questioned the basic tenet of the Helmholtz theory: that it is the lens which is solely responsible for changing the focal length of the eye.
The theory is eminently reasonable. It seems to be borne out by the anatomy of the eye. Among older people, who progressively lose elasticity of the lens, refractive error is assumed to be an inevitable concomitant of the passing years, so much so that graphs have been drawn showing loss of accommodation with increasing age. Furthermore it is actually possible to see changes in the curvature of the lens: reflections in the front and back surfaces may be observed by using a small flashlight. These Purkinje images, as they are called, are taken as the next best thing to observing the act of accommodation in a cross-sectioned living eye. And, as further evidence in support of the Helmholtz theory, science would cite the apparent ease with which glasses correct optical errors.
Another serious obstacle to acceptance of the Bates method was the personality of W. H. Bates himself. Having found empirically that the Helmholtz theory was lacking, he was far too quick to formulate a rival theory. Bates's proposal was that the eye accommodates, not by a change in the shape of the lens, but by a change in the shape of the eyeball itself, this change being brought about by the six extrinsic muscles which control the movement of the eye in its socket. Such an idea was rejected as nonsense, the more so when Bates adduced less-than-convincing evidence in some of his scientific papers dealing with accommodation in animals. From then on he became a subject of ridicule and professional hostility. His insights into the psychology of vision were ignored, as were the successes he achieved in his consulting room. These successes convinced him he was right and his colleagues wrong; he became more and more exasperated, and the dogmatic tone of his Perfect Sight Without Glasses verges, in places, on the aggressive. This did little to win over his critics.
The Bates method was served no better by some of the people who set themselves up as teachers. For every conscientious teacher of the method there were several who understood nothing whatever about it and saw in it only a means of exploiting the desperate patients whom orthodoxy had failed. In consequence, any suggestion that there might be something in visual re-education is now dismissed as outright quackery.
This attitude of the ophthalmic profession has perhaps, in part, consciously or otherwise, been influenced by another consideration. Although by no means all members of the profession profit from the trade in glasses, there is no question but that there is a huge vested interest in the correctness of the Helmholtz theory.
Yet another obstacle stands in the way of the Bates method. Results are usually slow in coming and require of the student a good deal of application, even faith. It is so easy to go for the instant solution that few people give the method a fair chance. The person who has improved his or her vision is such a rarity that few opticians will have encountered any evidence that the method works. Those cases that have come to light have certainly been explained as examples of anomalous but spontaneous improvement which would have happened anyway.
The final obstacle to acceptance of the method is the curious nature of refractive errors and the perpetuating effect that glasses have on them. Glasses tend to fix and make permanent errors that would otherwise, in time, correct themselves. The longer glasses are worn, the more intransigent the errors become, and the less believable it becomes that they could ever be cured.
And yet, despite all these difficulties, the method persists. It enjoyed special popularity in the 1930s and 1940s, particularly after its enthusiastic endorsement by the writer Aldous Huxley, whose book on the method, The Art of Seeing (Chatto & Windus, 1943), has rarely been out of print since. There have been other books too, of varying quality. In one of the better ones, published in 1957, the Bates teacher C. A. Hackett analyses the results of 10 years' work in which she treated 2180 cases of refractive error. Of these, over 75 per cent achieved lasting improvement, of whom about 45 per cent (over a third of all students) were able to do without their glasses entirely.
Besides the thousands of people who have derived benefit from teaching, there are presumably many who have achieved some success working alone. As Huxley points out, a book of instruction is no substitute for a good teacher, but in the absence of a teacher a book of instruction is better than nothing. It is my hope that I have presented in the following chapters an exposition which is clear, understandable, and designed to bring the wonderful benefits of the Bates method to all who care about their eyesight and are dissatisfied with present forms of treatment. It is also my hope — even conviction — that future generations will regard the wholesale dispensing of glasses as yet another pitiable example of a misguided fashion in medicine, as quaint as wholesale bloodletting or trepanning, and almost as barbarous.CHAPTER 2
The Visual Process
To succeed with the Bates method no knowledge of anatomy or the psychology of vision is necessary. All that is needed is to follow the instructions in Part Two, and you may prefer to skip this and the next two chapters for the time being. However, even a slight acquaintance with the visual process will let you evaluate the reasoning behind the instructions and this in turn is likely to help your progress, for you will see that the method is as logical as it is mild. Understanding this will also, to a certain extent, prepare you for the very considerable astonishment of discovering for yourself that the method works.
The anatomy of the eye
Vision, of course, is the sense that animals have evolved using light to provide information about their surroundings. The simplest animals of all are, like plants, sensitive only to light itself. With increasing complexity, animals become capable of discerning contrast, movement, images, colour, and stereo depth.
Compared with that of the other senses, the potentiality of vision is very great, for it is capable of yielding detailed and highly specific information at a distance as well as near to. This is of profound importance for survival; among those animals whose way of life demands good vision, the evolution of the eye has reached incredible levels of development.
The eye of man is not the most structurally complex in the animal kingdom, but it is certainly one of the most advanced, serving a brain which is the most sophisticated creation evolution has yet produced. The quality of this computer is matched by the quality of its major input devices for external stimuli — the ears and the eyes.
In structure, the human eye is a typical vertebrate eye, of a pattern common to all mammals. It is a hollow sphere (actually a spheroid) filled with fluid under slight pressure. This pressure maintains the shape of the sphere.
The eye may be thought of as being divided into two compartments, front and rear, by the lens, an elastic, convex body about eight millimetres across. A perfectly clear fluid, the aqueous, fills the front compartment, while the larger rear compartment is filled by the more gelatinous vitreous, the third component of the optical media — the transparent contents of the sphere through which light must pass.
In anatomical terms, the sphere itself is made up of three distinct layers. These are the sclera, the uvea and the retina.
The sclera is the outermost layer, the "white" of the eye, an extremely tough, fibrous sheath which protects the delicate structures within. At the front of the eye the sclera is modified into the cornea, a transparent, dome-shaped window which allows light to enter the eye.
The uvea consists of three parts: the iris, the ciliary body, and the choroid membrane. The iris lies just behind the cornea and is a muscular ring whose contractions can alter the size of the pupil, the aperture at its centre through which light gains access to the interior of the eye. The iris contains the pigment (brown, green, and so on) which gives the eye its "colour". Having passed through the pupil, light now passes through the lens, which is attached round its edge by a ligamentous membrane, the zonule, to the muscles of the ciliary body. Movements of these muscles alter the convexity of the lens, changing its focal length. The third and final part of the uvea is the choroid membrane. This is the network of blood-vessels lining much of the sclera, and provides the principal blood-supply for the inside of the eyeball.
The innermost layer of the eye is the retina, an exceedingly complex and delicate membrane of nerve-cells which includes the all-important photoreceptors. The photoreceptors are of two types, the rods and the cones. Rods are sensitive to dim light and register only shades of grey, while cones work in good light and are the source of colour vision.
Organisation of the retina
During the development of the human embryo, the forebrain bulges into buds which are destined to become the optic cups; the retina is actually an outgrowth of the surface of the brain, a kind of outpost where the visual information is not only generated but also receives preliminary processing.
There are some 130 million photoreceptors in each retina but only a million nerve fibres in the optic tract — the "cable" running from the retina to the brain. Thus each fibre must be shared, on average, by about 130 photoreceptors. Part of the work of the retina is to achieve this sharing without loss of picture quality. This feat is performed in the layers of specialised cells found between the photoreceptors and the nerve fibres. It is assisted by the way the photoreceptors are distributed throughout the retina.
The outer edges of the retina contain relatively few photoreceptors, mostly rods, and provide vision which may be compared to that of primitive animals. At the very periphery of the retina, indeed, there is no conscious vision at all, merely an awareness of movement and contrast. When you see something "in the corner of your eye" and automatically turn to see it better, you are responding to signals generated in this portion of the retina.
Further in towards the centre, the photoreceptors become more densely packed and the ratio of cones to rods increases. Occupying the centre is a region about 5.5 millimetres across, the macula lutea (usually abbreviated to "macula"). Towards the centre of the macula is a shallow depression called the fovea centralis or simply "fovea". The fovea is about 1.9 millimetres in diameter; at its centre, lying precisely on the visual axis, is an area only 0.35 millimetres across, the foveola.
In the fovea and foveola there are no rods, only cones, packed together so tightly that they look like rods. The cones reach their highest density in the foveola: the smallest cones here are less than one thousandth of a millimetre in effective diameter.
Throughout the retina as a whole, rods outnumber cones by about 18:1. It is the cones that are responsible for delivering precisely detailed vision. The importance of the cones is reflected in the generosity with which they are supplied with connections to the optic tract. Some of the cones in the foveola have exclusive use of a single nerve fibre. (In passing it is interesting to note that foveae, although found in certain fishes, lizards, and particularly in birds, do not occur in the lower mammals. Among mammals they appear only with the primates; the eye of the chimpanzee is remarkably similar to our own. Man's highly developed fovea, with the sharp sight it provides both at a distance and near to, has been one of the chief assets in his career as first a hunter, then a farmer, and now a technologist.)
The photoreceptors contain pigments which are bleached by exposure to light. This chemical change is converted into the electrical stimulus which then passes along the nerve to the brain. Once bleached, the pigments in any given photoreceptor take a little while to be replaced. Exposure to a very bright light will completely bleach a whole area of the retina and for a time its sensitivity will be impaired. This is the reason for the familiar after-images experienced after looking at anything very bright.
The muscles of the eye
Selection and control of the image falling on the retina is carried out by three muscle systems, two located inside the eyeball itself and the third outside.
The first of these systems is the iris. As has already been said, the iris is a muscular ring whose central aperture, the pupil, may be varied in size. As any photographer knows, to get the best from his film he must vary the aperture according to the prevailing light intensity. Controlling the amount of light entering the eye, though, is not the primary function of the iris, for, while the area of the pupil changes over a ratio of only about 16:1, the range of light intensities in which the eye works varies over a ratio of at least 1,000,000:1. The main function of the iris is probably to restrict the incoming light to the macula, except at times (such as dawn or dusk) when maximum sensitivity is needed. The pupil also contracts for near vision, "stopping down" the "camera" of the eye so that depth of focus is enhanced.
The pupil opens and closes automatically in response to the amount of light falling on the retina. In other words, there is feedback from the retina to the iris.
This idea of feedback is encountered several times in the study of vision. It is important in accommodation — the process in which the eye adjusts itself to focus on near or far objects. The feedback in accommodation comes from the part of the brain where perception takes place; if the image is out of focus, orders will automatically be sent to readjust the focusing mechanism.
Now we come to the central controversy of the Bates method: the means whereby accommodation is achieved. The currently accepted belief is that accommodation is attained solely through the action of the second internal muscle system of the eye, the ciliary body.
In this chapter the orthodox theory will be described, although even here there is dispute and uncertainty among ophthalmologists about the exact mode of action of the ciliary muscle and its nerve supply.
For distance vision the lens needs to be relatively flat, but to bring the converging rays from a near object into sharp focus, the lens must become more convex. (More about this is explained at the beginning of the next chapter.) The lens consists of a soft central filling enclosed by an elastic capsule. The wall of the capsule is thinner in some places than others, and its natural tendency is to bulge into a convex shape. Unless tension is applied to the capsule by way of the zonule, therefore, the soft filling will tend to form into a convex shape and so decrease the focal length of the lens.
Looking at Figure 1, it would seem evident that, because the more convex shape is the natural resting state of the lens, an effort has to be made only when distance vision is needed. Surprisingly, however, the opposite is the case. The lens is kept under permanent tension by the zonule, so that the usual shape is flattened and suitable for distance vision. When near vision is required, the ciliary muscle contracts, pulling the ciliary body forward. The diameter of the ciliary body (remember it is shaped like a ring) is thus reduced, tension in the zonule eases, and the capsule and with it the substance of the lens assumes a more convex shape.
Excerpted from Improve your Eyesight by Jonathan Barnes. Copyright © 1987 Jonathan Barnes. Excerpted by permission of Souvenir Press.
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