Our eyes are our greatest asset, but sometimes our brains can trick our eyes into seeing something that is not there or into not seeing something that is there.
I am told that our eyes can only take in something like 4,000 bits of information despite the fact that there are millions of bits all around us. That means at any given time, our brains are filling in the blanks with previously stored information. The place where the brain fills in the information is called a blind spot and this happens because the place where the optic nerve enters the eye has no photo receptors and this cannot receive any sensory information.
Sensei once told us that to hide the blind spot in our eyes we should turn our heads slightly away from the target. He said that there are more rods and cones on the outer parts of the eye which makes sense and would minimizes the blind spot.
After long bouts of meditation I also notice that my field of vision increases. So one could improve their field of vision with some type of guided exercise or meditation.
I also read an article that using cellphones, computers and tablets is causing people's field of vision to decrease. So on one hand our new technologically advanced lifestyle could hurt our ability to be good martial artists.
For a martial artist, the moment when one blinks or when the vision is obscured for even a moment is the moment when the opponent will attack. Understanding this calls us to study just how our eyes work and take great care of our eyes. Our opponents are just waiting for us to blink or look the wrong way in order to move into our blind spots.
I found this website with a bunch of tests that illustrate blind spots and how are eyes work. I have posted a few and added the website below if you want to try more.
Instructions: Close left eye and fix right eye on the cross. Place eyes about 12 inches (30 cm) away from the monitor (distance may vary depending on the screen resolution) and notice the dot disappears. .
www.personal.kent.edu/~rmuhamma/OpticalIllusion/illusion.html