Many people working on reversing their myopia are confronted with the question on how much they should reduce their diopters by. Endmyopia recommends reducing ones spherical correction by 0.25 diopters at a time, why is that?
Endmyopia works by leaving you a little under-corrected for close-up and distance. This ensures that your eyes see a small amount of blur (more specifically, myopic defocus). It’s then necessary to clear up the remaining blur, to achieve clarity. Active Focus is the mechanism that enables your eyes and visual cortex to bridge that small gap between blur and clarity.
So what happens if you drop down by more than 0.25 diopters? Say, 0.5 diopters or more. The focal point ends up further away from the retina giving you a bigger blur challenge, reducing your diopter bubble and shrinking your distance to blur.
There are some notable downsides to this approach for you to consider:
- If you are under corrected by too much it takes a lot more effort to get clarity on what you are looking at. The whole premise is that everything you do becomes a habit and many things take place subconsciously. This can only work if the discrepancy between clarity and blur/distorted vision is small. If you need to actively work on clarity because your diopter-bubble is too small a lot of stimulus is lost because you have to actively work your way through it and it takes much more time. With a smaller under-correction on the other hand it should be happening easier/semi-automatically. If you drop down by more than 0.25 diopters it is a serious possibility that you’re missing out on good stimulus. Jake explains this very clearly in these videos:
By having more myopic defocus it’s not only harder to achieve clarity in a static manner, but in motion it becomes next to impossible. Think about travelling by car, bike or just walking. While you are looking at something and there’s motion involved it’s a lot harder to achieve clarity, because what your are looking at is moving relative to your position. Your ciliary muscle has to adapt to this focal distance, Active Focus has to achieve the necessary clarity much faster and your visual cortex has to decode the data that comes in quicker to give you the proper clear vision. If you undercorrect too much this is hardly going to be possible, because it takes much more time and effort to achieve the desired clarity when motion is involved.
There is also a real risk of invoking blur adaptation. Blur adaptation means that your eyes and visual cortex become habituated to blur at a certain distance. Blur adaptation makes it pretty much impossible to improve because you aren’t working towards clarity anymore. Your visual system just accepts that there’s blur and there’s nothing that it can do to solve it. See Jake’s video on that here:
- If the available light reduces it’s even harder to get that necessary stimulus. If you are under-corrected in too much of a manner you may very well be eliminating all the stimulus you could be getting in low light/dark conditions. Many EM students even increase their correction for these circumstances because of this.
All the things metioned above add up to one simple thing. You are reducing the stimulus you are giving your eyeballs if you drop your correction by too much. What you want is stimulus that is happening as much as possible and is manageable. If you reduce the stimulus you may even slow down your progress instead of speeding things up by reducing more.
A few exceptions that are sensible:
- If reducing more than the average 0.25 diopters still brings you to 20/40 vision in less than ideal lighting conditions it may be a good choice for your new normalized.
- If there’s some nice natural (sun)light available and you don’t have much problems achieving the clarity required for that important stimulus, it could be utilized properly. Keep in mind that this should be considered your “peak prescription”. It’s important to return to your normalized when appropriate. See more on that here: https://endmyopia.org/how-to-getting-the-most-out-of-your-peak-prescription/
Some good links:
Report from @MattE: https://endmyopia.org/matthew-dropped-diopters-fast-hit-plateau/
Great video on this matter by @MattE: https://www.youtube.com/watch?v=6ELPRoAOzLs
One local example: https://community.endmyopia.org/t/next-steps-after-reducing-too-fast/4667?u=laurens
And another one: https://community.endmyopia.org/t/constant-daily-headaches/4372?u=laurens