Scientists develop implant that transmits visual signals to the brain, helping the blind see

Wednesday, November 02, 2016 by: Daniel Barker
Tags: blindness, retinal implants, biotechnology

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(NaturalNews) New technology has been developed that may allow blind people to see, using an implant that transmits visual signals from the retina directly to the brain.

A group of researchers from the University of Pisa published a study in the journal PLOS Biology detailing the development and use of the implant, which could soon make it possible for thousands of blind people to regain their vision.

The study involved patients suffering from Retinitis Pigmentosa (RP), a hereditary condition that causes a person to lose sight gradually until they become totally blind. The patients were given perceptual and brain response assessments before receiving prosthetic retinal implants.

Six out of seven patients were able to 'see' with the use of implants

Once the implants were in place, six out of seven subjects were able to "see" visual stimuli.

From the Express:

"The implant works by sensing visual signals and sending them to the brain by stimulating axons of retinal ganglion cells.

"Scientists used an MRI scanner to see how much patients reacted to visual stimulus such as flashes of light.

"They also observed increased brain activity as a result of the implants.

"And the more patients practised spotting the flashes of light, the more their brain responded to the light and the more they improved."

Retraining the brain to "see" again can take time, especially for those whose sight has been lost for many years.

Restoring sight takes time and practice

The researchers acknowledged the fact that the "plasticity of the primary visual cortex retained by the adult brain is limited, especially after many years of blindness," but noted that subjects who practiced more with the implants were more successful at regaining their vision.

"The recovery of vision depended on the amount of time and practice the subject experienced with the implant, implying that the reorganization process takes time to develop," the researchers wrote.

Co-author Professor Maria Morrone said that the study was the first to track the neural changes of visual areas in the brains of those with retinal implants, and to show that response to visual stimuli can be restored – even after years of complete blindness.

The Argus II retinal prosthesis is designed to stimulate cells in the retina of the eye, which then transmit visual signals to the brain. A pair of glasses with a built-in camera sends the signals to the implant, which then activates the retinal cells.

After the implants were surgically installed, six out of seven of the subjects were able to detect high-contrast stimuli, and after some practice, could perform basic behavioral tasks, such as locating a bright shape on a screen and "reading large, 100-percent contrast characters."

Subjects were also able to navigate a physical space based on the visual stimuli received in the brain. Although the visual signals may be somewhat primitive at this point, presumably the technology will improve over time, along with wearers' abilities to process the signals.

Being able to track neural activity with MRIs while the subjects detect the visual stimuli may help in the development of future implant technology, the researchers said.

These implants may prove effective in restoring sight to those suffering from RP and others with various visual impairment issues. RP affects only about one in 4,000, but around one in 30 people suffer some vision loss.

As technology evolves – along with our ability to map and understand the brain – we are undoubtedly going to see some breathtaking new developments. For example, implants such as the Argus II could eventually be used to not only restore vision to the blind, but to enhance vision capabilities in people with normal sight.

The age of the Bionic Man is upon us. The question is: Are we ready for it?

Sources:

Express.co.uk

MedicalDaily.com

Journals.PLOS.org