Going blind? This microchip could help you

11 May 2015

This microchip could help combat the onset of blindness

Researchers are developing a microchip that can be implanted into your eyeball to help combat the onset of blindness.

By attaching microchips to eyeballs, scientists can already restore vision in certain rudimentary instances.

But researchers in Vienna feel tweaking the electrical signals emitted by the implanted technology could advance the science further.

“Making the blind really see – that will take some time,” says TU Wien’s Frank Rattay, one of the lead authors of the report.

“But in the case of certain diseases of the eyes, it is already possible to restore vision, albeit still highly impaired, by means of retinal implants.”

Close, but no cigar

At the moment, basic chips installed in humans can convert light into electrical pulses, which are used to then stimulate the requisite cells in the eyeball.

Apparently, the problem is our eyes are immaculately complicated, meaning at the moment contrast is almost impossible to deal with – perhaps intelligent design was a little to clever, and we can’t quite grasp a digital substitute.

Generally speaking, the triggers that scientists can control in a damaged retina actually set off more than what they want.

“But it might be possible to stimulate one cell type more than the other by means of special electrical pulses, thus enhancing the perception of contrast,” says Rattay.

By using calcium as the particular measurement – concentrations, and the transport of such, proved key – the team discovered ON and OFF cells, which react differently to light.

This seems the key to the next stage of ‘curing’ the onset of blindness but, as Rattay says, “it will take some time.”

Here’s the technical description of the video above, which portrays a computer simulation used by the team:

A small patch of the retinal network is simulated by a computer simulation. One retinal ganglion cell and 20 connected bipolar cells are modelled with experimentally traced cell geometries. A disc electrode, depicted as white circle when turned off and as red circle when switched on, activates both cell types simultaneously by generating an electric voltage across the retina.

The cells respond to electric stimulation by changing their membrane voltage. Biophysical models of the membrane kinetics in retinal ganglion cells lead to so-called action potentials cells – the most important signal mechanism in the human body. These propagate along the axon of the ganglion cell which projects towards the brain.

Gordon Hunt was a journalist with Silicon Republic