Rex, the bionic man

Technology is turning into reality many of the utopias of science fiction and shortens time between what writers imagine and what scientists can do. The latest example is Rex, the first fully bionic man, which apparently has much in common with Steve Austin, the artificial man who starred the seventies television series called The Man of The Six Million. 

The bionic man is being built from $1,000,000 of limbs and organs by leading UK roboticists Richard Walker and Matthew Godden. All his vital organs were built in a laboratory and it is considered to be the most complete bionic man achieved by science so far.

This bionic man, on display in the Science Museum in London, has also synthetic blood and robotic limbs. With a face that resembles humanity, Rex incorporates some of the latest advances in prosthetic technology: - A prosthetic foot and ankle developed by Massachusetts Institute of Technology professor Hugh Herr), - A SynCardia Systems artificial heart - A bionic ear from Macquaire University in Sydney - An eye made of a camera mounted in Rex's glasses and an artificial kideny from University of California - An artificial trachea, first received by a cancer sufferer in 2011, from Royal Free Hospital, London - A spleen from Yale, Connecticut. - An artificial pancreas from De Montfort University, Leicester One of the experts who participated in its construction, Richard Walker, told the BBC that the result of the work is "very significant", since it has allowed to know "how close are prosthetic technology to rebuild the whole human body." "There are some vital organs missing, like the stomach, but 60 to 70 percent of a human has effectively been rebuilt" said Walker. Bertolt Meyer, one of the creators of Rex who was born without a right hand and wears a bionic prosthesis, said that "the great promise of technology is that it can wipe out disabilities." 

However, technology developers claim that not all technology is useful for replacing body parts. For example, hands can not move without bionic human muscle and brain signals. “What we are beginning to achieve is building prostheses which look like human body parts, but we are a long way away from making ones which relay sensory information the way the human body does.” Once medical science improves, as it inevitably will, Meyer says the next step will be tackling the sticky ethical issues which will arise. “Should I be allowed to cut off my real hand and replace it with something, does that give me an unfair advantage over people who cannot afford this?” asks Meyer. “I’m not saying that is going to happen but these are questions that should be on the table before that technology becomes available.”. 

http://www.euronews.com/2013/02/12/meet-rex-the-world-s-first-real-bionic-man/

Visual implant helps the blind read Braille

A group of French and American researchers has succeeded in developing an ocular device that has allowed to transmit first braille patterns directly into the retina of a blind patient who has been able to read four letter words accurately and quickly.

"In this clinical test with a single blind patient, we bypassed the camera that is the usual input for the implant and directly stimulated the retina. Instead of feeling the braille on the tips of his fingers, the patient could see the patterns we projected and then read individual letters in less than a second with up to 89% accuracy," explains researcher Thomas Lauritzen, lead author of the paper.

The study, published in "Frontiers in Neuroscience, was conducted by researchers at Second Sight, the company that developed the device, called the Argus II, "the artificial retina", has already been mentioned in this blog in a post last April. As I said then, the concept is similar to the development of cochlear implants: there is a visual implant a grid of 60 electrodes attached to the retina to stimulate patterns directly on nerve cells. For this study, researchers stimulated six of these points on the grid to project braille letters.

Image: Copyright Gadget Review.

"There was no input except the electrode stimulation and the patient recognized the braille letters easily. This proves that the patient has good spatial resolution because he could easily distinguish between signals on different, individual electrodes." says Lauritzen.

The patient correctly identified 89 percent at one point, 80 percent in the case of two points, to 60 percent in the case of three words, and 70 percent of 4-letter words.

Source: 

http://www.newscientist.com/article/dn22525-implant-lets-the-blind-read-braille-with-their-eyes.html

Never-before-seen implant

In my last post, I discussed about what we can expect from developments in cochlear implants, a technology that has been with us for more than 30 years. As it was briefly explained, cochlear implants stimulate the cochlea by means of electrodes, making possible for the brain to interpret this information as sound. In this way, I have been thinking if it wouldn't be possible to do the same for blind people. A quick search on google and... voila, I found that we already have what it is called "a retinal stimulator" or "artifical retina" implant.

Some history I found about it: In the mid-1980s, the neuroophthalmologist Joseph Rizzo III was researching retinal transplants to restore blind people's vision. One day, removing a lab animal's retina, a tissue-thin membrane that lines the back of the eyeball's interior, he made a tremendous discovery. "The moment I made the cut, I said to myself, 'What in the hell are you doing?'" Rizzo recounts. He realized he was cutting nerve connections that are actually spared in many forms of blindness. The retina's light-sensing cells (photoreceptors, or rods and cones) die off in retinitis pigmentosa and age-related macular degeneration, which affect millions worldwide; but the nearby neurons that ferry the signals from those cells to the brain remain intact.

Electrode implanted in the back of the eye (© Springer Science) 

So Rizzo conceived what he called "a retinal prosthesis", a device intended to bypass the damaged eye structure. This has evolved to what we call nowadays and artificial retine which works as follows: a miniature camera mounted in eyeglasses captures images and wirelessly sends the information to a microprocessor (worn on a belt) that converts the data to an electronic signal and transmits it to a receiver on the eye. The receiver sends the signals through a tiny, thin cable to the microelectrode array, stimulating it to emit pulses. The artificial retina device thus bypasses the damaged photoreceptor cells and transmits electrical signals directly to the retina’s remaining viable cells. The pulses travel to the optic nerve and, ultimately, to the brain, which perceives patterns of light and dark spots corresponding to the electrodes stimulated. Patients learn to interpret these visual patterns. A lot of research and effort has been put in this technology since then and finally last year the first such device was approved in Europe for commercialization: The Argus II Retinal Prosthesis System by Second Sight.

But this shouldn't be perceived as making possible for blind people to see. In the same way that cochlear implants only partially restore hearing, the artificial retinal is not intended to fully restore vision, but to artificially provide electrical signals that the brain can interpret as shapes. Research is made towards increasing the number of electrodes thus increasing the "reslution" of the images that can be perceived. The ultimate goal is to design a device with hundreds to more than a thousand microelectrodes (DOE Artificial Retina Project). This resolution will help restore limited vision that enables reading, unaided mobility, and facial recognition. Also, some research goes towards the use of human tissue to improve the communication between biological tissues and artificial sensors. Researchers in Italy have now reported the functional interfacing of an organic semiconductor with a network of cultured primary neurons. Their novel approach represents a new tool for neural active interfacing, which is a simpler alternative to the existing and widely used neuron optogenetic photostimulation techniques, and avoids gene transfer, which is potentially hazardous. In words of one of the researches, Guglielmo Lanzani, "This new approach to the optical stimulation of neurons may stimulate further work towards the development of an artificial retina based on organic materials."

Sources:
http://www.springer.com/engineering/biomedical+engineering/book/978-0-387-77260-8

http://www.nanowerk.com/spotlight/spotid=19863.php