How to Determine Your Dominant Eye
Almost everyone has a dominant eye and it may be the right or left eye. One’s dominant eye is not necessarily the right eye for a right-handed person or left for a left-handed person.
The dominant eye is the one that looks directly at each object you focus on. If you think of how your two eyes are set a few inches apart and think of one looking directly at something, let’s say at an armchair -- then you’ll see that the other eye is looking at a slight angle at that armchair. This is the non-dominant eye.
What to Do
- In the middle of a piece of paper cut a square or circle a little over an inch wide
- Hold the paper with both hands out in front of you, centered on your face
- Look through the hole with both eyes at anything you see that is not moving
- Continue focusing on this object through the hole and gradually bring the paper closer until you are touching your face
You will find that you have the paper over one of your eyes. This is your dominant eye. It has been the one focusing directly on the object all along and the other eye was looking at it at a slight angle. This test is called the Dolman method of determining ocular dominance.
There are other ways of determine your dominant eye, such as the Miles test and the Porta test. Some must be done for you by another person.
Because we can see the same object simultaneously from two slightly different angles, we have depth perception. The brain puts together the two images, noting certain cues such as the relative sizes of objects and differences in lighting, and is able to estimate how far away that object is compared to other things in view. We learn to do this very early in life.
The cues used by the brain can be either binocular or monocular – coming from both eyes or coming from just one eye. A person who loses one eye can still have some depth perception because of the monocular cues.
Examples of Monocular Cues
- Apparent motion of stationary objects (relative to the background) when you are moving – distant objects seem not to be moving whereas nearby objects seem to move quickly
- Apparent size of moving objects – a ball, for instance, coming towards you seems to grow larger whereas a ball that you throw away from you seems to grow smaller
- The vanishing point (convergence of two parallel lines in the distance) allows a person to calculate relative distances of objects along those lines
Examples of Binocular Cues
- Disparity between each eye’s image (known as stereopsis) is greater when the object is close than when it is distant and that gives the brain an accurate idea of how far away the object is
- Degree of stretching of the muscles which focus the eyes on an object; the two eyes converge more to focus on a near object than they do to focus in the distance
It is thought that about 65 percent of people have a dominant right eye. Some studies have suggested that left-eye dominance is more common among migraine sufferers. Eye dominance can be weak or strong and very strong cases may be caused by amblyopia (“lazy eye”) or strabismus (misaligned eyes).
When monovision is being considered for vision correction (one eye corrected for distance and the other for near vision), an eye surgeon will consider your ocular dominance in assessing how satisfied you might be with this solution. Depending on your particular vision status, the dominant eye might be corrected for far vision or for close vision.