Nov 7, 2010

Bionic implants: 'We have the technology'

For the first time in more than a decade, Miikka Terho was able to glance at a clock and read the time. It was a simple task, but one he had been unable to do since he was robbed of his sight by disease. Mr Terho, 46, a financial consultant from Finland, was one of three patients who had their sight temporarily restored using artificial light sensors and microchips placed on the retina at the back of their eyes by doctors in Germany.
This extraordinary melding of man and machine proves that we finally have the technology to create real-life bionic humans. In the 1970s TV series, The Six Million Dollar Man, Lee Major’s character had his body rebuilt using bionic technology, leaving him “better, stronger, faster”. Now, cutting-edge research is producing synthetic body parts to replace damaged tissues, limbs, organs and senses. In most cases it is used to improve a patient’s quality of life, but in others it is saving lives.

Here we examine how science can potentially kit out a human being from head to toe to create a real bionic man.

Brain
By far the most important, and also the most complex, organ in the body is the brain. It controls our movements and our breathing, makes sense of the world and stores the memories that help form our personalities. Damage to the brain from accidents or illnesses such as strokes can be catastrophic, ranging from paralysis to memory loss. But some scientists believe they may have found a way to repair this damage – a prosthetic brain.

Dr Theodore Berger, from the University of Southern California, has been developing a device that can be implanted into the brain to restore memory functions, modelling the complex neural activity that takes place in the hippocampus, which is responsible for forming new memories.

The device – a microchip that encodes memories for storing elsewhere in the brain – has been tested using tissue from rats’ brains, and researchers are planning trials on live animals. They hope it will provide a way of restoring memory function in patients who have suffered damage to their hippocampus from a stroke, an accident or from Alzheimer’s disease.

Eyes
Around one million people in Britain suffer from two of the most common forms of blindness: macular degeneration and retinitis pigmentosa. But doctors in Germany last week restored sight to three blind patients by implanting chips lined with electronic sensors – similar to those found in digital cameras – into the back of their eyes. When light hits these sensors, they produce electrical impulses that pass into the optical nerve behind the eye and into the brain. The patients reported being able to distinguish objects such as fruit and cutlery, and even read their own name.

Miikka Terho was one of the first to have the implant and saw his life transformed over the three-month trial, before the implant was removed. He went from being completely blind to being able to make out fuzzy black-and-white shapes that allowed him to read the time.

“When I first got the implant I could tell I was seeing something, but I couldn’t really make out what it was – it was like my sight was a muscle that I hadn’t used in a long time and it needed training to get used to recognising things again,” he says.

“Later I was able to see people and tell if someone lifted their arm or if someone was taller than someone else. They were too fuzzy to distinguish faces, but being able to see like that would help me to be more independent and walk in unfamiliar surroundings – to live a more normal life.”

Professor Eberhart Zrenner, who led the research at the University of Tuebingen, has already begun work on improving the detail that the patients can see by changing the power supply – currently the chip has an external supply that must be transmitted through the skin via a magnetic link.

Read more at The Telegraph

No comments:

Post a Comment