The Real Reason Not Everyone Can Unfocus Their Eyes

If you've never tried to unfocus your eyes, go for it: Focus on something a few feet away and then slowly let your vision go blurry. Many people learn the skill in childhood as one technique for viewing stereograms (also known as "Magic Eye Images"). Other people learn the ability after they catch themselves daydreaming and want to replicate the way everything looks right before they snap out of it.

Unfocusing your eyes can put a sort of soft haze on the world. But not everyone is lucky enough to have the ability. It makes stereograms next to impossible, but for someone who can't unfocus their eyes, that's the least of their concerns. 

Some people have esotropia which is also known as "a lazy eye," according to Brown University. This is when one eye seems to turn inward toward the nose. The American Association for Pediatric Opthamology and Strabismus states that children suffering from this form of strabismus — meaning any condition where the eyes don't align — can lose their 3-D vision, the ability for both eyes to work together, or all vision in the eye that is "lazy."

Esotropia is usually diagnosed in childhood, but that doesn't mean that the ability to unfocus your eyes is guaranteed as an adult. Around the age of 40, people can lose the ability to focus or unfocus their eyes. According to the American Academy of Ophthalmology this common experience is known as presbyopia. It's why many adults end up with reading glasses.

The root of the problem

Both of these issues have one important aspect in common: they affect the function of ciliary muscles. According to the Encyclopedia Britannica these muscle fibers are absolutely key when it comes to focusing and unfocusing our eyes. The muscles relax when we look at things far away and contract when we focus our eyes up close.

Our eyes usually adjust to focus on whatever we turn our attention to. But when it comes to stereograms, eye exams, and even 3-D movies, we may want to change our focus. And that's where these issues are most noticeable. Despite our best efforts, the cilia don't cooperate and our vision suffers as a result.

No matter the age at which it occurs, an inability to control eye focus means that the ciliary muscles aren't working properly. Whether you've always had trouble focusing your eyes or the trouble has just started, it is important to get to an eye doctor. Contacts and glasses can help while the doctor ensures there are no other issues.