Eons before there were any schools or printing presses, electric lights or moving pictures, the evolution of the eye was complete.
In hypermetropia (commonly but improperly called farsightedness, although the patient with such a defect can see clearly neither at the distance nor at the near-point) the eyeball is too short from the front to the back, and all rays of light, both the convergent ones coming from near objects and the parallel ones coming from distant objects, are focused behind the retina instead of upon it. In myopia it is too long from the front to the back, and while the divergent rays from near objects come to a point upon the retina, the parallel ones from distant objects do not reach it.
it is customary to instill atropine … into the eye, for the purpose of paralyzing the ciliary muscle and thus, by preventing any change of curvature into the lens, bringing out “latent hypermetropia” and getting rid of “apparent myopia.”
The instillation of atropine into the eye is supposed to prevent accommodation by paralyzing the muscle credited with controlling the shape of the lens.
During sleep the refractive condition of the eye is rarely, if ever, normal. Persons whose refraction is normal when they are awake will produce myopia, hypermetropia and astigmatism when they are asleep. Or, if they have errors of refraction when they are awake, these will be increased during sleep. This is why people awake in the morning with eyes more tired than at any other time, or even with severe headaches.
When the eye regards an unfamiliar object, an error of refraction is always produced.
A sudden exposure to strong light, or a rapid or sudden change of light, is likely to produce imperfect sight in the normal eye, continuing in some cases for weeks and months.
Noise is also a frequent cause of defective vision in the normal eye.
Under conditions of mental or physical discomfort, such as pain, cough, fever, discomfort from heat or cold, depression, anger, or anxiety, errors of refraction are always produced in the normal eye or increased in the eye in which they already exist.
It will be noted that they color is always less intense than when seen with the naked eye, and since the perception of form depends upon the perception of color, it follows that both color and form must be less distinctly seen with glasses than without them … However, if the sight is seriously defective, the color may be seen better with glasses than without them.
After people once begin to wear glasses, their strength in most cases has to be steadily increased in order to maintain the degree of visual acuity secured by the aid of the first pair … A person with myopia of 20/70 who puts on glasses giving him a vision of 20/20 may find that in a week’s time his unaided vision has declined to 20/200.
The strong concave glasses required by myopes of high degree make all objects seem much smaller than they really are, while convex glasses enlarge them.
But myopia is usually accompanied by astigmatism, and this, it is believed, can be overcome in part by alterations in the curvature of the lens.
In other words, it is assumed that the supposed muscle of accommodation has to bear not only the normal burden of changing the focus of the eye for vision at different distances, but also the additional burden of compensating for refractive errors. Such adjustments, if they actually took place, would naturally impose a severe strain upon the nervous system, and it is to relieve this strain-which is believed to be the cause of a host of functional nervous troubles-quite as much as to improve the sight, that glasses are prescribed.
Primarily, the strain to see is a strain of the mind, and, as in all cases in which there is a strain of the mind, there is a loss of mental control.
The remedy is not to avoid either near work or distant vision, but to get rid of the mental strain which underlines the imperfect functioning of the eye at both points.
By constant repetition and frequent demonstration and by all means possible, the fact must be stressed that perfect sight can be obtained only by relaxation.
The eyes are rarely, if ever, completely relaxed in sleep, and if they are under a strain when the subject is awake, that strain will certainly be continued during sleep, to a greater or lesser degree, just as a strain of other parts of the body is continued.
The fact is that when the mind is at rest nothing can tire the eyes, and when the mind is under a strain nothing can rest them.
No matter how good the sight, it is always possible to improve it.
Of two equally good pairs of eyes, one will retain perfect sight to the end of life and the other will lose it in the kindergarten, simply because one looks at things without effort and other other does not.
The eye with normal sight never tries to see … It never tries to bring out the point by staring at it, as the eye with imperfect sight is constantly doing.
The eye possesses “perfect vision” only when it is absolutely at rest.
The act of seeing is passive.
Mental strain of any kind always produces a conscious or unconscious eyestrain, and if the strain takes the form of an effort to see, and error of refraction is always produced.
Many children can see perfectly as long as their mothers are around, but if the mother goes out of the room they may at once become myopic, because of the strain produced by fear.
The health of the eye depends upon the blood, and circulation is very largely influenced by thought. When thought is normal-that is, not attended by any excitement or strain-the circulation in the brain is normal, the supply of blood to the optic nerve and the visual centers is normal, and the vision is normal. When thought is abnormal the circulation is disturbed, the supply of blood to the optic nerve and visual centers is altered and the vision is lowered. We can consciously think thoughts which disturb the circulation and lower the visual power; we can also consciously think thoughts that will restore normal circulation and thereby help to cure errors of refraction and many other abnormal conditions of the eyes. We cannot by any amount of effort make ourselves see, but by learning to control our thoughts we can accomplish the end indirectly.
If the relaxation is only momentary, the correction is momentary. When it becomes permanent, the correction is permanent.
This relaxation cannot, however, be obtained by any sort of effort. It is fundamental that a person should understand this; so long a she thinks, consciously or unconsciously, that relief from strain may be obtained by another strain, the improvement will be delayed.
When the mind is under a strain the eye usually goes more or less blind. The center of sight goes blind first, partially or completely, according to the degree of the strain, and if the strain is great enough the whole or the greater part of the retinal may be involved.
The muscles of the face and of the whole body are also at rest, and when the condition is habitual there are no wrinkles o dark circles around the eyes.
All the methods used in the eradication of errors of refraction are simply different ways of obtaining relaxation, and most people, though by no means all, find it easiest to relax with their eyes shut. This usually lessens the strain to see, and in such cases is followed by a temporary or more lasting improvement in vision.
This is done by covering the closed eyes with the palms of the hand (the fingers being crossed upon the forehead) in such a way as to avoid pressure on the eyeballs.
But even with the eyes closed and covered in such a way as to exclude all the light, the visual centers of the brain may still be disturbed, the eye may still strain to see; and instead of seeing a field so black that it is impossible to remember, imagine, or see anything blacker, as one ought normally to do when the optic nerve is not subject to the stimulation of light, a person will see illusions of lights and color ranging all the way from an imperfect black to kaleidoscopic appearances so vivid that they seem to be actually seen with the eyes. The worse the condition of the eyesight, as a rule, the more numerous, vivid, and persistent these appearance are. Yet some persons with very imperfect sight are able to palm almost perfectly from the beginning, and are therefore very quickly relieved. Any disturbance of mind or body, such as fatigue, hunger, anger, worry or depression, also makes it difficult for patients to see black when they palm, persons who can see it perfectly under ordinary conditions often being unable to do so without assistance when they are ill or in pain.
It is impossible to see a perfect black unless the eyesight is faultless, because only then is the mind at rest; but some people can without difficulty approximate such a black nearly enough to improve their eyesight, and as the eyesight improves the deepness of the black increase.
The majority of such people may be greatly helped by the memory of a black object.
It is impossible to succeed by effort, or by attempting to “concentrate” on the black. As popularly understood, concentration means to do or think one thing only—but this is impossible, and an attempt to do the impossible is a strain which defeats its own end. The human mind is not capable of thinking of one thing only. It can think of one thing best, and is at rest only when it does so, but it cannot think of one thing only. A patient who tried to see black only and to ignore the kaleidoscopic colors which intruded themselves upon her field of vision, becoming worse and worse the more they were ignored, actually went into convulsions from the strain, and was attended every day for a month by her family physician before she was able to resume the treatment. This patient was advised to stop palming, and, with her eyes open, to recall as many colors as possible, remembering each one as perfectly as possible. By thus taking the bull by the horns and consciously making the mind wander more that it did unconsciously, she became able, in some way, to palm for short periods.
It is impossible for the eye to fix a point longer than a fraction of a second. If it tries to do so, it begins to strain and the vision is lowered … IN the case of a few exceptional people, a point may appear to be hold for a considerable length of time and the subjects themselves may think that they are holding it, but this is only because the eye shifts unconsciously, the movements being so rapid that objects seem to be seen all alike simultaneously.
But while the illusions of normal sight are an evidence of relaxation, the illusions of imperfect sight are an evidence of strain.
“flying flies,” … being symptoms of nothing except mental strain
In myopia it may be a benefit to strain to see fine print, because myopia is always lessened when there is a strain to see near objects, and this has sometimes counteracted the tendency to strain in looking at distant objects, which is always associated with the production of myopia.
If persons who find themselves getting presbyopic, or who have arrived at the presbyopic age, would, instead of resorting to glasses, follow the example of the gentleman mentioned by Dr. Hommes and make a practice of reading the fines print they can find, the idea that the decline of accommodative power is “a normal result of growing old” would soon die a natural death.
Muscae volitantes is simply an illusion resulting from mental strain.
The specks are never seen in other words, except when the eyes and mind are under a strain, and they always disappear when the strain is relieved.
When the eye looks at an unfamiliar object it always stains more or less to see that object, and an error of refraction is always produced.
It is impossible to see anything perfectly when the mind is under a strain, and if children become able to relax when looking at familiar objects, they become able, sometimes in an incredibly brief space of time, to maintain their relaxation when looking at unfamiliar objects.
When you have become used to the strong light, raise the upper lid of one eye and look downward as the sun shines on the sclera. Blink when the desire to comes, or when you lose the power of relaxation.