Australian researchers from Monash University Gippsland say that combining sensory information may help improve the sight of people receiving visual prosthetics. They claim that by stimulating the senses of "touch" and "vision" at the same time, the brain is better able to interpret what it is "seeing."
Bionic eyes send electrical impulses to the brain, but many people struggle to make sense of what they are "seeing," particularly when they first receive the prosthetic.
George Van Doorn, along with colleagues Barry Richardson and Dianne Wuillemin, set out to explore if people could learn to "see" more quickly if more than one sense was stimulated at a time.
As children grow and hone their understanding of the world, they instinctively cross-reference between the senses. Smells, touch and taste are just as important to them as what they can see and hear, and they all help build up a bigger picture.
Using a gentle touch, in conjunction with the information received from a bionic eye, may help people learn to 'see' more quickly.
So, the researchers' approach seems to be building on human development.
Their theory, published in the International Journal of Autonomous and Adaptive Communications Systems, proposes that delivering a tactile copy directly to the skin the same time as the signal reaches the visual cortex in the brain will help the patient interpret the new stimuli.
Van Doorn explains:
"If you're a person who's never seen anything, and you get a bionic eye, basically what you can see initially is just little spots of light or dark. Because these people have never had vision, interpreting this visual information is extremely difficult, which is why we're suggesting that touch be used in conjunction with vision, in the hope that this will help the recipient of a bionic eye learn to 'see' faster."
Drawing information from multiple sources
As a learning process, this has obvious advantages - cross-referencing the information from all the senses gives a more detailed and more accurate picture of the world.
Van Doorn explains:
"You could have one camera stimulating the retina or cortex of the eye, and another stimulating the tongue at the same time so people could get information from both senses at once. Then, if they miss some of the information provided by one sense, they may get it from the other. This adds to the information sent to the brain."
Disappointingly though, the findings have not lit medical science's fire, perhaps because many scientists' field of expertise is so focused. Van Doorn had hoped the results would trigger a shift in thought, but he says this is proving more difficult than anticipated.
"Most people still believe using information from only one sense will be good enough (when developing visual prosthetics), so they don't bother combining the two (vision and touch). While this might be true, we believe success is more likely with more sources of sensory information."
Despite the difficulties the researchers are facing, they are still hoping to take their studies further with the help of grant money or teaming up with another group involved in bionic eye research.
Van Doorn says:
"I wouldn't have thought it was a revolutionary idea, but it appears to be, because we've certainly hit a wall in taking it further. I think many put it in the 'too hard' basket, which is a shame given the potential."
Scientists from Australia's Vision Centre recently discovered areas in the ancient brain that may help us interpret patterns. This research, reported in Medical News Today, may also be relevant for the development of bionic eyes.