Just as people have a dominant hand we use for writing and holding utensils, most of us have a dominant eye.(1) The dominant eye is not necessarily the best seeing eye, rather it is the one that provides more input to the visual center of the brain.(2) Eye dominance varies from person to person – some have a strong degree of dominance, and others less so.(1)
Taking advantage of the dominant eye can be important in a variety of activities. For example, in some sports like golf or baseball, positioning the head is important in ensuring the dominant eye can see clearly. When taking a photograph, using the dominant eye in the lens provides a better view of the shot and improved alignment.(1)
Here are two tests to determine the dominant eye: (3)
- Extend your arms out in front of you and create a triangular opening between your thumbs and forefingers by placing your hands together at a 45-degree angle (see animation).
- With both eyes open, center this triangular opening on a distant object — such as a wall clock or door knob.
- Close your left eye.
- If the object stays centered, your right eye (the one that's open) is your dominant eye. If the object is no longer framed by your hands, your left eye is your dominant eye.
- Extend one arm out, holding the thumb of that hand in an upright position. (Or you could use your index finger instead of your thumb.)
- Keeping both eyes open and focused on a distant object, superimpose your thumb on that object. (Don't worry if it looks like your thumb partially disappears — that's normal.)
- Alternately close one eye at a time.
- The eye that keeps your thumb directly in front of the object while the other eye is closed is your dominant eye.
Ophthalmologists test for eye dominance when a patient is getting monovision, with LASIK surgery or after the insertion of an intraocular lens after cataract surgery. In monovision, one eye is corrected for distance vision and the other for near vision. Generally, the dominant eye will be corrected for distance vision.(3)
Monovision works because the brain adjusts the visual system, according to a leading medical center. When the person focuses with the “near eye” on a near object, the brain partially suppresses vision in the distance eye. When the person focuses with the distance eye on an object in the distance, the brain suppresses vision in the near eye.(4)
In children, when there is a large difference in prescription between the eyes, there can be increased risk for amblyopia (lazy eye). Left uncorrected, the brain can “turn off” the weak eye, only relying on the dominant eye. Temporarily patching the dominant eye allows the weaker eye to get stronger.(3)
Edge Pharma, a 503B Outsourcing Facility, is a leader in compounded ophthalmic products. Visit our Ophthalmology Products page to learn more.
(1) Santos-Longhurst, A., reviewed by Griff, A. OD, healthline, Dominant Eye: Here’s Looking at You, https://www.healthline.com
(2) Heiting, G. OD, All About Vision, Dominant Eye Test: How to Find Your Dominant Eye, https://www.allaboutvision.com
(3) Porter, D., reviewed by Repka, M. MD., MBA, American Academy of Ophthalmology, Eye Dominance, https://www.aao.org
(4) Henry Ford Health System, IOL Monovision for Cataract Surgery, https://www.henryford.com