• Tuesday, April 22nd, 2008

For those with myopia who understand the tight and fixated feeling of ‘staring’, the concept that the eyes must move to see is readily embraced.  When we teach vision activities, or ‘games’, we frequently mention the necessity of returning movement to the eyes and the visual system.  In this article I will discuss why the eyes need to move for clear eyesight.

First we discover that even when the eyes appear to be stationary, looking at a single point in space, they are in fact, moving.  The moves they are making are the tiny involuntary vibrations known as saccadic movement, or saccades.  Many of those who make regular visits to the optometrist have never heard of saccades, yet they are the most vital basic function of all eyesight. 

Most people are familiar with the basic principles of vision; that light enters the pupil, falls on the retina and stimulates the retinal cells. The information acquired by these cells is transferred in a constant stream via the optic nerve to the visual cortex. Here these signals are interpreted into the vision that we utilize pretty much all day, everyday, for every interaction with the external world.

What is not always widely known is that it is the action of the saccades that brings the light into the eyes.  If they were to sit and wait for the light traveling at all angles around us to fall into the pupils, very little would find its way into what is in fact a really very small aperture.  Alfred Yarbus, a Russian biophysicist who researched eyesight and saccadic movements, demonstrated that if all saccadic movement stopped, within 3 seconds we would have a ‘blank field’, meaning there would be virtually no input to the retinal cells.  That’s how important saccadic movement is to eyesight. 

I like to think of the saccades as ‘scooping’ light from the surroundings with each flickering rotation. From here it’s easy to embrace the idea that the faster the saccadic movement, the more light is entering the pupil and the more information the retina is receiving.  In the end the effect is clearer eyesight. 

So the question becomes, what is slowing down the saccadic movement? Ask any sports coach what muscle state allows for the quickest responses, the most flexible action, and they will tell that it is not a tight muscle.  No, it’s the relaxed muscles that are ready to respond, to move easily and quickly at their task. Here a major portion of the physical relationship between tension in the visual system and blurred eyesight becomes evident.

There is a common habit among those with refractive error.  It’s most popular amongst myopes, but hyperopes and presbyopes do their share.  The habit I am speaking of is staring, and short of the saccades stopping, it’s pretty much the opposite of the quick, mobile eyes that are expressing good saccadic movement. 

One of the first steps we take in improving eyesight is to become aware of our staring habits and their features.  Many myopes ask; ‘Which comes first, the stare or the refractive error?’  It’s a chicken and egg question, as myopia encourages staring and staring may assist in the development of refractive error. The reasons for this could include the effects caused by the common features of a really good stare. These include: tight eyes which tend to fix quite rigidly on one point, tense neck and shoulder muscles, tight belly (which also relates to anxiety), shallow tense breathing, a posture which takes the neck and spine out of alignment*, and often a reduction in blinking frequency. All of these have an effect on the way that the eyes and brain can function.

*The posture usually varies for the different refractive errors, but has the same overall effect.  Myopes tend to crane their neck forward and squint at things in the distance, straining to bring them closer.  Hyperopes and presbyopes will tend to lean back, kinking the neck in an effort to bring handheld materials further away.

To begin improving eyesight we first become aware of the ‘negative’ habits helping create an overall situation in the body that is conducive to blur.  The more we notice that we are doing these things, the more we can deliberately replace them with habits that encourage good eyesight.  Good visual habits assist muscles to relax and accomplish faster saccades. They start with practicing the opposite of the ‘stare features’ described above then go further into actively doing vision games on a regular basis. 

  • Begin with becoming aware of when you are staring at things and use the Magic Nose Pencil technique to change from looking at the world with a fixed gaze. Instead loosely sketch with your imaginary Nose Pencil around and on each object.  Do this with full attention for a period of time each day to really get your system used to it as a new habit, but also do it in little bits whenever you find yourself staring.
    Your head movements will be tiny on small, close objects, and large and sweeping on large, distant objects. My favourite way to express the feeling of this is that when your head makes the large movements around objects; your eyes are free to make the tiny saccadic jumps.  Think of your head as the vehicle and your eyes the passengers, sitting relaxed yet active and enjoying the view!

 

  • For tight neck and shoulders do some self massage on a regular basis and get others to massage these muscles when you can.  Stretch your upper body regularly, especially if you do hours of desk/computer work, or do strong physical labour. Notice when your shoulders have crept up around your ears and deliberately relax them.

 

  • Notice when you hold your breath, breathe quickly or only in the chest (any situation that makes you anxious). At these and all times, deliberately breathe slowly and deeply, letting your belly expand.  Relax your abdomen and breathe deeply, all the way down to your belly button.

 

  • Do your best to sit and stand straight, and use good back support for sitting and strength tasks. 

 

  • Remember to blink frequently (every 3 – 4 seconds, or around 20 times per minute is average). 

All of these new habits will contribute to a more relaxed visual system and self, increased ability towards good saccadic motion and better eyesight, and may help those with good eyesight maintain it without further effort.  For those with visual blur at any distance, specific vision games will continue this process by actively retraining the eyes and brain towards clearer vision. When healthy eyes ‘sparkle’, perhaps it’s the effect of flickering fast and joyful saccadic motion!

 

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One Response

  1. 1
    A Erle Ribbans 

    Very interesting and enlightening. I do have a problem with staring this perhaps a cause of my short sightedness. I will endeavour to use these exercises on a regular basis and also take regular trips to the Galaxy.
    Well done very well narrated and explained. Thank you for this wonderful experience and look forward to SEEING the results…

    Regards Erle Ribbans

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