D-Bone
Apr 27th '07, 10:54 AM
Researchers have set their sights on bypassing the normal routes of bionics to hook video cameras deep into the brain, allowing the blind to see. The bionic eye system has already proved promising in monkeys.
The goal is to one day provide vision for blind people using twin video cameras worn as a pair of glasses that transmit signals wirelessly to an implant in the brain.
Decades of studies have tried to develop prostheses that restore sight. One approach generates images by electrically stimulating healthy neurons in the retina, the light-sensitive tissue lining the inner eyeball , and thus mimic the effects of inbound light. The other aims to electrically stimulate cells in the cortex, the outer layer of the brain where visual signals are processed.
Both approaches have drawbacks and have achieved limited success.
The retina is a very delicate, fragile membrane that is prone to damage. And the complexity within the cortex makes it more difficult to generate intelligible pictures with the second method.
With retinal stimulation, each neuron that gets stimulated is responsible for a single dot in any image that is seen. In cortical stimulation, "you stimulate one site in the cortex, you get one spot of light, you stimulate another site you get another spot, but if you stimulate both at once you don't necessarily get the sum of the two, but you might get a third spot," explained computational neuroscientist computational neuroscientist Nicholas Hatsopoulos of the University of Chicago in Illinois. "You can't really connect the dots."
Read More: http://www.livescience.com/humanbiology/070427_bionic_eye.html
The goal is to one day provide vision for blind people using twin video cameras worn as a pair of glasses that transmit signals wirelessly to an implant in the brain.
Decades of studies have tried to develop prostheses that restore sight. One approach generates images by electrically stimulating healthy neurons in the retina, the light-sensitive tissue lining the inner eyeball , and thus mimic the effects of inbound light. The other aims to electrically stimulate cells in the cortex, the outer layer of the brain where visual signals are processed.
Both approaches have drawbacks and have achieved limited success.
The retina is a very delicate, fragile membrane that is prone to damage. And the complexity within the cortex makes it more difficult to generate intelligible pictures with the second method.
With retinal stimulation, each neuron that gets stimulated is responsible for a single dot in any image that is seen. In cortical stimulation, "you stimulate one site in the cortex, you get one spot of light, you stimulate another site you get another spot, but if you stimulate both at once you don't necessarily get the sum of the two, but you might get a third spot," explained computational neuroscientist computational neuroscientist Nicholas Hatsopoulos of the University of Chicago in Illinois. "You can't really connect the dots."
Read More: http://www.livescience.com/humanbiology/070427_bionic_eye.html