To see if your own eyes are hardening, look no further than your phone, which should require no exertion; you’re probably already there. Keep peering at your screen, reading and staring, snubbing life’s third dimension and natural hues. The first sign of the eyes’ becoming teeth is the squinting at phones. Next comes the reflexive extending of the arm, the impulse to resize letters into the preschool range. And at last the buying of drugstore readers.
Modern medicine offers little apart from magnifying glasses to treat presbyopia (from the Greek presbus, meaning “old man”). But those $3.99 specs will get you on your feet just fine, which is to say, you can once again relish your phone without squinting or arm-stretching. A remedy for farsightedness evidently succeeds to the degree that it restores a woman or man to the comfortable consumption of texts, email, ecommerce, and social media on a glazed rectangle of aluminum alloys held at a standard reading distance of 16 inches. With reading glasses we live again.
Doesn’t this seem like an unwholesome loop? The eyes may be unwell, but the primary object of our eyesight seems corrosive. We measure our vision against the phone, all the while suspecting the phone itself is compromising our ability to see it.
Even if we don’t say out loud that failing vision has something to do with our vastly narrowed visual field, our bodies seem to know what’s up. How convenient, for example, that you can turn up a phone’s contrast and brightness with a few taps. If perception can’t be improved, objects can be made more perceivable, right? But then the brightness seems, like morphine, to produce a need for more brightness, and you find yourself topping out, hitting the button in vain for more light only to realize that’s it. You’ve blinded yourself to the light that was already there.
There are at least two recorded cases of something called smartphone blindness. The New England Journal of Medicine notes that both patients had been reading their phones in bed, on their sides, faces half-hidden, in the dark. “We hypothesized that the symptoms were due to differential bleaching of photo-?pigment, with the viewing eye becoming light-adapted.” Differential bleaching of the eyes! Fortunately, smartphone blindness of this kind is transient.
目前，已经至少出现了两例记录在案的智能手机眼盲症。《新英格兰医学杂志》（The New England Journal of Medicine）注意到，两例患者都喜欢在黑暗中侧身斜眼看手机。“我们推测，随着眼睛越来越适应屏幕亮度，两眼视觉细胞中的光敏色素会不同程度地褪去，从而导致了这些症状。”唯一值得庆幸的是，智能手机眼盲症是暂时的。
Lately, when I pull away from the screen to stare into the middle distance for a spell, I take off my glasses. I try to find a tree. If I’m inside, I open a window; if I’m outside, I will even approach a tree. I don’t want mediation or glass. The trees are still strangers; I hardly know their names yet, but I’m testing myself on leaf shapes and shades of green. All I know so far is that trees are very unlike screens. They’re a prodigious interface. Very buggy. When my eyes settle after a minute or two, I-what’s that expression, “the scales fell from my eyes”? It’s almost, at times, like that.