Flitcroft, meanwhile, thinks the problem lies in the clutter of objects clouding your visual field. Just take a look around you and you will see what he means. “If you look at a laptop screen, everything behind the screen is out of focus to quite a large degree,” he says. “And then if you look up from the laptop to a clock, you have a huge flip – the clock is in focus, but there are lots of things close to you in periphery, that are blurred.” Wherever you fix your gaze, there is always a blur that plays with the eye’s feedback mechanisms. Outdoors, however, things tend to lie at a greater distance, providing a clearer image that helps to regulate the eye’s development.

Such insights are hopefully not just of academic importance, since they could eventually direct us to new treatments. Luu, for instance, is hoping to put together a trial that offers blue lamps to short-sighted children. Not only does Luu hope it could slow further decline; it may actually reverse it; during his study of chicks, he found that a few hours a day under a blue lamp undid the damage of the red lights and returned the chick’s vision to normal.

Chance discovery



Flitcroft points out that there are promising trials of contact lenses that can reduce blur in the peripheral vision. He is also optimistic that an eye drop, called atropine, could be helpful. The drug has long been known to slow down the signalling that triggers eyeball growth and short-sightedness. Its unwelcome side-effects – such as causing pupil dilation and generating halos around sources of light – meant that it was once dismissed, but a chance finding recently showed that it is equally effective at a just one hundredth the original dose. At those levels, the side effects should be minimal – a discovery that has now sparked renewed interest in the eye drops.