Hebrew U scientists help blind 'see with eye music'
Device for sensory exchange activates visual cortex to help those born blind describe objects, letters and words.
By JUDY SIEGEL-ITZKOVICHbrain(photo credit: Wikicommons)
By activating their visual brain cortex, people who were born blind can describe objects and even identify letters and words, with the proper stimulation and using a device for sensory exchange developed by Hebrew University researchers.The research team, headed by Prof. Amir Amedi of the Edmond and Lilly Safra Center for Brain Sciences and Institute for Medical Research Israel-Canada and including doctoral student Ella Streim- Amit, has just published their findings in the journal Neuron; a summary of their research also appeared in the journal Science.They developed a unique training program for seeing using the device, which transfers visual information to the blind via their healthy senses.The device translates pictures into tones; after a few dozen hours of training, the blind from birth can identify images and put them in visual categories such as faces, houses, parts of the body, ordinary objects and textures.They can also locate people, identify facial expressions and read letters and words, thus being able to “see” enough to exceed the World Health Organization minimum to be regarded as sighted.Amedi said on Sunday that for decades, it is has been known that if the visual cortex does not receive visual information after birth, it doesn’t properly develop the normal visual structure and skills, and thus visual reconstruction was thought to be impossible. But when the team checked what happens in the brains of blind people who learned to “see” via sounds, their visual cortex functioned even though they had learned to process images only when they reached adulthood, he said.The researchers also found that the brains of the blind from birth had visual preferences similar to those with normal sight when they reacted to different kinds of visual stimulation. For example, the part of the brain used for reading showed that in the blind, as in the sighted, there was increased activity in reaction to pictures of letters and words. In addition, this region proved to be so flexible that one of the blind people tested was able to react to such images after a two-hour training session.“The brain of adults is more flexible that what we assumed,” Amedi said.“These findings show it may be that the brains of blind people, even for long periods, can ‘wake up’ to process vision through rehabilitation, including new medical developments such as retinal implants [artificial eyes].”Additional research in the field by Amedi’s team with Dr. Sheli Levi-Zedek that was published in the journal Restorative Neurology and Neuroscience presented a device for sensory exchange. Using it, the blind from birth could cover their eyes and still carry out rapid and exact movements toward targets. Using a non-invasive device called “eye music” involving pleasant music, the blind were able to “see” with sounds.
In training sessions of as little as half an hour, 18 blind from birth people were able to tell the difference between a red or a green apple.This paves the way for future hybrid devices, including a receptor implanted in the eye together with “eye music.”
