A videogame is helping adults with amblyopia improve their vision.
A research team led by Dr. Robert Hess from McGill University and the Research Institute of the McGill University Health Centre has used Tetris to treat what is commonly known as “lazy eye.” By distributing information between the two eyes in a complementary fashion, the video game trains both eyes to work together, which the research team says is counter to previous treatments for the disorder, such as patching.
“This medical breakthrough provides direct evidence that alleviating suppression of the weaker eye, by forcing both eyes to cooperate, increases the level of plasticity in the brain and allows the amblyopic brain to relearn,” the team affirms. The research is published in the journal Current Biology.
Amblyopia is the most common cause of visual impairment in childhood, affecting up to 3% of the population. It is caused by poor processing in the brain, which results in suppression of the weaker eye by the stronger eye.
Previous treatments for the disorder, which have focused on covering the stronger eye in order to force the weaker eye to work, have proven only partially successful in children. The approach has proven even less ineffective in adults.
“The key to improving vision for adults, who currently have no other treatment options, was to set up conditions that would enable the two eyes to cooperate for the first time in a given task,” says Dr. Hess, senior author of the paper.
According to Dr. Hess and his colleagues, the adult human brain has a significant degree of plasticity and this provides the basis for treating a range of conditions where vision has been lost as a result of a disrupted period of early visual development in childhood. The researchers used the videogame Tetris beause it involves connecting different shaped blocks as they fall to the ground.
“Using head-mounted video goggles we were able to display the game dichoptically, where one eye was allowed to see only the falling objects, and the other eye was allowed to see only the ground plane objects,” explains Dr. Hess. “Forcing the eyes to work together, we believed, would improve vision in the lazy eye.”
The researchers tested a sample of 18 adults with amblyopia. Nine participants played the game monocularly with the weaker eye, while the stronger eye was patched; the other nine played the same game dichoptically, where each eye was allowed to view a separate part of the game. After two weeks, the group playing the dichoptic game showed a “dramatic improvement” in the vision of the weaker eye as well as in depth perception. When the monocular patching group, who had showed only a moderate improvement, was switched to the new dichoptic training, the vision of this group also improved dramatically, according to the research team.