Possible cause of myopia found | City Health Berlin

The intellectual with thick glbades is a stereotype of myopia. In fact, the so-called myopia increases with increasing education level: every second cycle of high school in Germany is short-sighted and every year the training reaches on average about a quarter of diopter. Now, scientists at the Tübingen University Hospital have found a possible explanation for the phenomenon: poor eyesight may be due to reading.

Eye growth leads to myopia

To understand this, you need to know how myopia develops. In myopia (nearsightedness), the eye develops too long, the image is clearly displayed in front of the retina and you can see off the focus. Animal experiments have shown that two specific types of cells are crucial for eye growth: stimulation of ON cells tends to inhibit eye growth, while stimulation of OFF cells may improve. On the cells, evaluate whether the center of their light-sensitive area is brighter and the environment darker, while out-of-cell cells badess whether the center is darker and the environment is brighter . In normal vision, both types are also irritated.

Black and White Could Be the Problem

But reading books, magazines, manuscripts and screen texts. , is it different? According to Tübingen researchers, it is mainly stimulated OFF cells.

"This suggests that black text on a light background promotes the development of myopia, and that the light text on a black background inhibits myopia," say researchers Andrea C. Aleman, Wang Min and Frank Schaeffel in "Scientific Reports Nature". "Invert text contrast would be an easy way to stop the development of myopia, because more and more time is spent working and reading on screen and tablet."

Clearly: white writing on a black background could prevent myopia. The proof has already been demonstrated in the first experiments: the research team had tested subjects on the computer by reading both dark text on a light background and light text on a dark background. After only 30 minutes, they were able to measure using optical coherence tomography (OCT) that the choroid thinned by reading the black text, and thicker by reading the text with the opposite contrast.

Choroid reacts to the contrast of the text

The choroid is the layer behind the retina. The changes in their thickness predict how the eye will grow in the near future. If the choroid becomes thinner, this indicates the development of myopia, it becomes thicker, the growth of the eyes is inhibited, that is to say that it does not develop myopia.

If a reversal of the text contrast can prevent myopia in real life is not yet certain. The Tuebingers want to explore this issue in a future study with school children.

Photo: © baranq – Fotolia.com