To mend a lazy eye, doctors will often patch over the opposite eye for extended periods to encourage the weaker eye to work harder. However, scientists at Dalhousie University in Halifax recently discovered a faster, more effective method.
Researchers restored normal vision to a test group of kittens with induced lazy eyes by actually reprogramming the part of the brain responsible for interpreting vision to that eye—kind of like flipping a light switch.
The kittens were quarantined to a dark room with zero photons of light for ten days, based on the theory that darkness can cause some parts of the visual system to revert to an early stage in development, when there is greater flexibility. The kittens were placed in the room with their mother and litter mates, fed, cleaned, and cared for as per usual, and monitored by infrared camera.
“Immersion in total darkness seems to reset the visual brain to enable remarkable recovery,” explains Kevin Duffy, a neurobiologist and lead author of the study. “The idea is that the brain early on is very plastic.”
A lazy eye (or an amblyopia in scientific terms) is unable to focus in sharp detail, which can cause the development of a lazy eye, or misaligned or cross eyes, in children. Currently, amblyopia affects approximately 4-percent of children when the nerve pathway between the eye and brain doesn’t develop properly, sending blurred images to the brain, which the brain becomes accustomed to, and if left untreated can lead to permanent vision loss.
The results were “astonishing,” said Duffy. Pointing out that when kittens were removed from the complete darkness, “the vision of both eyes improved slowly but in lockstep and eventually reached normal visual acuity, in about 70 days!..[Plus] amblyopia didn’t develop [in the healthy eye]. So you end up getting recovery of vision in both eyes up to normal levels.”
The study brings one important question to mind for parent: If it were a matter of your child’s eyesight, would you agree to stay in total darkness with your child for 10 days?
Not so fast, “much more research needs to be done before a darkness therapy could translate for use in children,” says Duffy. “Researchers still have a lot of questions to answer.
He cautions that in the meantime, parents who have a child with a lazy eye shouldn’t try this at home.