For some, people who wear eyeglasses are either a "nerd" or a "geek." The truth is, eyeglasses in people have nothing to do with their intellectual capacity or lack of social skills.
Most people with glasses suffer nearsightedness — an eye condition by which researchers believed was developed during childhood.
According to a new study, the more time a child spends indoor, the more likely he or she will become nearsighted, literally. Nearsightedness is medically known as myopia.
The findings may open "new therapeutic target to control myopia," said Greg Schwartz, lead investigator of the study published online on Jan. 26.
Nearly 30 percent of U.S. population suffer from myopia. The number of people affected by the condition worldwide run up to more than a billion and still rising.
A myopic person's eyeball grows too long or the clear front cover of the eye, known as cornea, is too curved. It cannot focus the incoming light correctly and objects seen beyond two meters become blurred.
For years, no one knew what makes one eye grows too long or makes the cornea too curved. Not until this study, which is part of a larger research conducted by Schwartz, an assistant professor of Ophthalmology and Physiology at Northwestern University Feinberg School of Medicine.
Retinal Cell: The Missing Key?
This cell in the retina, the investigators found out, is believed to be the missing link in the search for a cell that carries the signal.
The cell, labeled as "ON Delayed," is highly sensitive to light and is, therefore, responsible for determining whether an object is in focus. It also controls how the eye grows and develops.
"We potentially found the key missing link," Schwartz declared.
How Much Time Indoors Is Too Much?
The green and blue wavelengths, referred to as the brighter lights, are the characteristic of outdoor lighting while indoor lighting is redder.
Once indoor, the red/green incoming signal to the eye is likely to confuse the ON Delayed ganglion cell, the eyeball's control mechanism.
The incoming mixed light signal may cause the ON Delayed to tell the eye that it is not focusing rightly, so it has to grow more and may cause the dysfunction.
In a separate study using chicks, the subjects were raised in surrounding with red lights are likely to be nearsighted than those who were raised in blue or green surroundings.
Schwartz believed the indoor lighting, with its red/green contrast, causes the dysfunction that will lead to myopia.
This may sound good news for those who love outside action. Most researchers agree that people who love outdoor environment are less likely to be myopic, well, literally and figuratively.