A study published recently in Current Biology found that some exercises can improve vision around the edges of the eye's blind spot.
Everyone has a natural blind spot in each eye. In order for us to see, light must enter the eye and land on light-sensitive cells in the retina at the back of the eye, which create electrical bursts. Then the optic nerve carries these electrical impulses to the brain, where they are interpreted as a picture. There aren't any cells to detect light where the optic nerve passes through the retina at the back of the eye, so there is no vision in that area.
In research conducted at the University of Queensland, Australia, ten people were tested using images of colored, moving lines that were sometimes inside and sometimes outside the blind spot. Over the course of twenty sessions, the size of the blind spot was reduced by ten percent.
Researchers theorize that light-sensitive cells around the edge of the blind spot became more sensitive to light due to the exercises. The improvement did not transfer from one eye to the other, so each eye would have to be trained separately.
Improving vision around the physiological blind spot is not a priority for most of us. However, this research may point to ways to improve the vision of people suffering from blind spots due to age-related macular degeneration or other conditions.
Find Your Blind Spot
Most of the time we don't notice blind spots in our vision because they're not in our central vision, and the brain fills in the missing area. It's not fully understood how this filling in happens, but it seems to be a combination of information supplied by the brain of what is most likely to be in the missing area, and re-use of the electrical impulses produced by the areas of the retina circling the blind spot.
It's usually very easy to see your blind spot. To find your own blind spot, sit about a foot away from your screen, close your left eye and stare at the dot in the image. Move your head closer to and farther away from the screen, and the plus sign will disappear when it's in your blind spot. You can repeat the test with your left eye by staring at the plus, and watching for the dot to disappear as you move.

Eye Exercise Myths
Eye exercises have sometimes been proposed to improve vision in people who need glasses or other vision correction to see clearly. However, there is no research that shows exercises can improve visual acuity or change your glasses or contacts prescription.
Eye exercises are used for some people with strabismus or other eye-alignment problems. These exercises are for the muscles that control eye movement, and do not affect the vision correction prescription.