Normally our two eyes work together, but we can learn to separate them, and use one eye for close-up vision and the other one for far vision.
It’s like a drummer, who learns to play one rhythm with his feet on the pedals, and a different rhythm, a cross-rhythm, with his sticks.
About 100 years ago, an experiment was done by a man who made some glasses which turned everything upside down. He wore these for a week or so and found that after 3 or 4 days, everything looked normal and he was able to walk around without any mishaps. When he took them off, everything looked upside down! So he had to re-learn to see normally.
Our human brains are remarkable for what they can learn. Most of us have a dominant eye. In monovision, this eye is adjusted to see far distances, and the other eye adjusted to see close-up. Our brain can learn in about 6 or 8 weeks to adjust.
Monovision can be done using:
- Contact lenses
- Refractory surgery such as LASIK (blended vision)
- An implanted intraocular lens
Whichever way it’s done, the brain learns to see in this new way. There’s a compromise involved too, as for most people who have monovision, their visual clarity isn’t perfect at either close or far distances. But it’s workable, and for some people, especially those who live active lifestyles, it’s a good solution.
Your eye surgeon will discuss the monovision option with you to see if you’d be a good candidate. If certain things are central to your lifestyle, you’d probably not want to have monovision:
- Any activities requiring very sharp distance vision
- Any activities requiring precise close-up vision
- A great deal of night driving