The flashes of reality

New science / technology allows the connection of an electronic "eye" directly to a person's brain

Uriel Brizon

The 39-year-old Jans lost his left eye in a work accident at the age of 17. He lost his right eye three years later, in another accident. In a demonstration for journalists in New York last June, Jans found his way in a room where various obstacles were placed, located doors and objects and finally even drove a car in the parking lot. This is not a medical miracle:

An electronic "eye" was installed on Lance. Jans's story was published in the September issue of "Wired" magazine. The article joins other articles, in various newspapers and magazines, that tell about the latest developments in technology that may bring about a revolution in the field of vision.

For about fifty years, scientists have known that electrical stimulation of the visual area in the brain of humans causes the appearance of points of light in the field of vision, even in those who have lost the light of their eyes. In a healthy person, the brain receives stimuli from the eye through the optic nerve. Artificial electrical stimulation activates those areas of the brain that receive the visual stimulus, and produces points of light, or flashes (Phosphenes) that simulate the action of the eye. Experiments conducted by the American researcher Wilder Penfield in the 50s showed that these points of light are not random, but appear in fixed places depending on where the electrical stimulation is done. This discovery led researchers to speculate that it would be possible to produce a technological device that would allow direct stimulation of the brain by a signal coming from an electronic camera, or in other words: an artificial electronic eye.

In the 60s and 70s, various attempts were made to develop an artificial vision system, but it became clear that this required more advanced technology than was available at that time. The 80s and 90s gave birth to a new generation of digital cameras, and in recent years small and powerful computers were developed as well as light sensors of the CCD type - tiny television cameras the size of a fingernail that are capable of producing a colorful and sharp image. At the same time, in the last two or three years, the ability to produce microscopic electrodes that allow the stimulation of nerve cells has developed precisely - almost to the point of being able to connect to each nerve cell individually. The combination of these technologies, plus the progress of the physiological research of the structure of the brain and advanced surgical techniques, are the elements that enable the first effective steps towards artificial vision.

Dr. William Duval, the man who developed and installed Yanes' artificial vision system, has in his laboratory the first model he developed in the 70s, a two-ton computer whose development cost was 25 million dollars. The current model of the system can be worn on the body, and is currently on sale for $115.

The system includes glasses on which a tiny camera is mounted, a portable computer, batteries and several electronic boxes mounted, together with the computer, on a belt. The glasses are connected by an electric cable to one of the boxes in the belt, and from another box cables lead to two connections located on the sides of the patient's head. The price, by the way, includes a flight to Portugal, where the surgery is performed to insert the electrodes into the skull. It is impossible to perform the surgery in the US due to restrictions by the US Ministry of Health.

Duval is one of the prominent figures in the field of artificial vision. He was born in Massachusetts in 1941, the son of an orthopedic surgeon. At the age of 13, he applied for a patent for an improvement he designed for an artificial pelvic bone; At the age of 14 he was already studying at the university. Duval says that the topic of artificial vision has been burning in his bones since he was a student in the 60s. In 1984, he established his own laboratory (the Duval Institute) where he and his team develop and sell various medical devices. Doval uses the proceeds from the sale of the medical equipment to finance his research in artificial vision.

In 1978 Doval performed the first installation of an artificial vision system. The patient was Jerry, a 52-year-old resident of Brooklyn who lost his eyesight at the age of 36. Jerry went through the operation unharmed. For years, the set of electrodes inside his head was left unused - both to make sure it did not cause inflammation and complications, and to wait for more advanced developments of the other system components. Only then did Doval begin testing the system's effectiveness.

In Jerry's head was installed a simpler and more basic version of the system that had recently been installed in Jans's mind. The number of electrodes in the intracranial device is smaller, and the original computer that used it is much weaker than the new system's computer. Even so, the system gave Jerry surprising abilities. On the website of the Duval Institute, you can watch it identify a human-like doll placed in different places in the room. Jerry finds a hat hanging on one of the many hooks on the wall. He walks over, takes the hat and places it with great precision on the doll's head. In an even more impressive demonstration, Jerry looks at a board hanging on a wall about a meter and a half away from him. A 15 cm letter E is drawn several times on the board, which is used for an eye test as in a standard eye doctor's examination: sometimes the letter faces the normal direction, another time it is upside down, and another time it is lying down. Jerry is asked to identify the direction the signal is facing, and he succeeds in doing so in all cases.

In an article published in 2000 in the newspaper of the Association for Internal Artificial Organs (ASAIO), Duval claimed that Jerry was even able to distinguish from the same distance 5 cm letters. It is important to emphasize that Duval works alone most of the time, and to some extent outside the academic establishment. Because of this, opinions and reviews of other scientists on the details of his work are absent. Criticism by research colleagues is essential to the continuation of the scientific process and due to its absence, at this stage, it is difficult to verify Duval's assertions.

Jerry Wayans describes what they see in terms of flashing lights in patterns. From the articles that have been published on the subject it is difficult to understand what exactly is the picture of reality painted in their heads; But they seem to be able to distinguish objects and different levels of brightness. The electrode assemblies implanted in their cerebral cortex contain several dozen electrodes. Some electrodes do not produce a response; Others cause, when activated, a single point of light to appear. Sometimes a single stimulus causes several points of light to appear at the same time.

How often is the patient required to come to the laboratory to go through the process of calibrating the device. The camera, mounted on the glasses, photographs what is in front of the patient; But as a result of the behavior of the physiological system, deviations may occur in the transition between the image in the camera and the image appearing in the patient's field of vision. During the calibration process, the laboratory team adjusts the electrodes in the device, according to the patient's testimony, so that what is in the center of the camera will cause points of light to appear in the center of his field of vision, what is on the right will cause points to appear on the right, etc.

After the calibration, a rough image of the external reality is created in the patient's mind - an image in the form of points of light that turn on and off. Instead of the millions of points of light (and color) that make up normal vision, Jerry Vians is satisfied with dozens of single points that describe the world. Lions, which has the latest system, has a greater number of points. The system in its current state is certainly not a substitute for natural vision. According to Jans, "This is currently very crude vision compared to normal vision, but it is a great improvement compared to blindness."

Duval, due to his independence and willingness to take risks, is the first scientist in the field of the application of artificial vision. But other groups working to develop such systems present a vision that does not fall short of his own. A research group operating with great vigor is located at the Moran Eye Institute at the University of Utah. It is headed by Prof. Richard Norman. The group developed a unique set of electrodes to stimulate the visual cortex in the brain, and did many experiments on animals. In the publications about the group's work, Norman emphasizes the subject of the whole stimulus. According to his perception, this is the heart of the matter. In the absence of a large amount of high-density electrodes, Norman claims, sufficient vision will not be produced. Norman aims to reach the stimulation of individual neurons, and produce a larger number of points of light, which will be sharper and more focused. According to him, without a large amount of precise electrodes, the image will remain vague and rough.

In the set of electrodes developed by the group, technologies for the production of computer chips and materials that prevent rejection of the implant by the body's immune system are applied. Experiments to implement the system in humans should begin soon. An alternative concept for artificial vision is being explored by several other groups. Within this concept, the researchers are trying to implant an electronic chip into the patient's eye, and not into his brain. The chip contains light sensors and is supposed to stimulate nerve endings inside the eye and thus replace the retina that has stopped working. This technique is not suitable for people who have lost their eyes, but it may help many people who have lost their sight as a result of diseases that impair the eye's ability to transform light into nerve stimulation.

At the Doheny Institute at the University of Southern California, researchers have developed a system in which a chip is implanted on the retina of the eye. The chip receives radio signals from a transmitter located behind the ear; The transmitter, in turn, receives data from a small camera mounted on the belt, and translates this data into signals that stimulate the optic nerve. The stimulus creates points of light in the patient's field of vision. Other groups developing intraocular systems operate at the University of Illinois at Chicago as well as Scandia Laboratories in New Mexico.

Scandia Laboratories even received a three-year grant of 9 million dollars from the American government, although in the past the administration refused to fund artificial vision research because it was not considered applicable.
Prof. Michael Belkin, director of the Laboratory for Ophthalmic Technologies of Tel Aviv University in Tel Hashomer, suggests seeing things in proportion.

Indeed, Belkin says, interesting research is being done in the field, but no significant experiments have yet been done on humans and it is still too early to determine whether artificial eyes will soon become commonplace. Belkin points to the rejection problem as a major factor, and claims that researchers will have to find a way to overcome the body's natural tendency to resist implants and electrodes.

If the efforts of the various groups are successful, we may see artificial eyes in widespread use in the future. Scientists and thinkers looking to an even more distant future estimate that artificial vision devices may even, at an advanced stage, offer capabilities that exceed natural human vision. It will be possible, for example, to connect an infrared sensor directly to the brain that will allow vision through walls, or a camera with magnification and zooming capabilities that will allow vision at great distances. Alternatively, the owners of the device will be able to connect directly to a TV receiver or to the computer's display card, and thus watch a movie or surf the Internet in a way that will cover the entire field of vision; That is, the user will be able to switch, at the push of a button, between seeing reality and watching a movie or wandering through virtual spaces. Will there come a day when people with normal vision will ask for surgery to install an artificial vision system? It's possible. But at this stage it is still just points of light.