Matthew Nagel suffered severe spinal cord damage in an attack five years ago, leaving his body paralyzed from the neck down and unable to breathe on his own. But after having electrodes implanted in his brain, Nagel, now 25, has been able to carry out simple daily activities independently, carrying things, opening e-mail, changing television channels and playing video games. What is even more incredible is that he engages in all of the above activities only by the power of imagination. Human brain computer perfect combination
This is a cutting-edge neural graft research experiment, led by the United States Brown University neurotechnologist John Donahue, Nagel is a part of the experiment. The researchers implanted a set of electrodes into Nagel's brain, which was able to convert the electrical activity generated by millions of neurons into brain signals that operated instruments outside his body so that he was able to operate computers and robotic arms with just his brain.
Nagel is able to use his mind to move a cursor on a computer screen, open e-mail, change television channels, operate a robotic arm to pick up and move things, and play simple computer games. While engaging in all of these activities, he can also speak like any able-bodied person.
Nagel was not the first patient to receive a brain implant, but he was the most successful. Some previous attempts to link the human brain to a computer had only limited success, with patients able to move a cursor only from side to side, and the operation was slow and laborious. Scientists have also experimented with technology that implants electrodes into the scalp, but these require months of training before patients can be truly flexible.
Potential for 'killer robots'
Some experts have warned that the rapidly developing technology could be used for more sinister purposes. In the United States, at least a dozen laboratories are engaged in research on human brain-computer interfaces, many of which have received more than 25 million dollars in funding from the U.S. military, which is very interested in developing "killer robots," which are controlled by soldiers and viewed as "machine warriors" with human brains. machine warriors".
If patients with mental problems due to Alzheimer's disease and other illnesses are implanted with electrodes, then challenging behavior can be controlled by suppressing antisocial tendencies and dealing with "acceptable" responses. British scientists on the evening of March 12 called the advance a landmark that will bring hope for recovery to hundreds of thousands of patients disabled by car accidents, strokes and other illnesses.
Before the trials on Nagel, it was unclear to scientists whether a person who had been paralyzed for years could still produce the brain signals needed for activity. But with just the first trial, it became almost clear that the implanted electrodes might be able to record patterns of nerve signals, and that his brain wasn't just transmitting "noise". Computers can filter and compile all kinds of neural signals.
The researchers were also thrilled with Nagel's reaction time with the device, which was 10 times faster than with the previous brain implant. Another team of researchers has made progress in speeding up the brain-machine interface. Their research has shown that it is entirely possible for users to exchange information at a rate equivalent to typing 15 words per minute on a keyboard.
Science gives humans a 'third hand'
Nagel learned how to move a computer cursor in just a few days, a skill that would have taken months for patients with electrodes implanted in their scalps. Initially, Nagor imagined that he was physically moving the computer cursor, but he quickly adapted to imagining that the cursor itself was moving. In this way, the computer cursor became his third hand or leg, as useful as his two hands and two legs.
The success of the technique depends on its ability to interpret the brain's electrical activity and translate it into useful activity. The researchers found that certain movements are accompanied by corresponding patterns of neurons firing, but the sensors can select only a small fraction of the total activity. Even simple actions such as raising an arm involve signals from multiple regions of the brain.
Professor Donahue visualizes the process as placing a microphone in a crowded room and trying to get all the talking points. As Nagel struggles to turn inexact thoughts into exact actions, the result is, of course, an uneven, imprecise movement, but over time Nagel's control of the cursor improves and he is eventually able to roughly draw a circle with it.
Disabled people may be able to get back on their feet again
Professor Donahue said that in the long term, the bulky cables attached to the patient's head and the mass of electronics should be removed. Miniaturization of the device would make the implant in the brain smaller, with the skull completely covering it, as in the case of a pacemaker. Signals can be transmitted wirelessly from the brain to a processor to set computers, robotic arms and other devices in motion.
Implants, of course, have some drawbacks, and some scientists argue that they are not the best treatment option for patients who are completely disabled. Some scientists also oppose experimenting on Nagel, saying the risk of brain damage from the practice is very high. If the patient's brain rejects the implant, it might put other researchers off the idea of pursuing the technology.
Also, the implanted electrodes are prone to inflammation and infection, and, as a result, the electrodes can lose their effectiveness. Professor Donahue is convinced that the only way to enable paralyzed patients to interact fully with their surroundings is through electrodes implanted in their brains. He says: "There is no other method that gives you the power you need to convert a noisy signal into something the patient can use."
Some other researchers are more ambitious. Miguel Niklas, a neurobiologist at Duke University in Durham, N.C., believes that the idea of using this technology to help disabled people get back on their feet is achievable.
Of course, this is only the first step in a long journey, and there is still a much longer road ahead, with many hurdles to overcome, such as different people responding differently to brain implants and the possibility that electrodes could become inefficient over time, among other things. Most of the patients with severe spinal cord damage are young, which could make their use of the technology decades long. The idea of using our minds to control the world around us used to exist only in science fiction movies. But today, with the rapid development of the latest generation of brain implant technology, the once-unattainable dream has now taken a major step toward reality, and the dream seems to be getting closer.
Yang Hsiao-wen Ren Qiu-ling compiled
The process of the "Idea Shift" experiment: Researchers implanted a chip called the "Brain Gate Neural Interface System" into a quadriplegic patient's motor cortex, with 100 electrodes on the chip's 4-square-millimeter surface. There are 100 electrodes, the patient imagines that he wants to complete the action, 100 electrodes sensors began to record brain activity, these signals are transmitted to the computer, through the computer decoding and processing and ultimately converted into motor commands, so that he can use his mind to check e-mail, control the TV, move the auxiliary robotic arm, the accuracy rate of 75% to 85%. A remote-controlled soccer match with the idea of the afternoon of June 23, in the laboratory of Tsinghua University Neural Engineering Institute, two were "striker" and "goalkeeper" of the robot dog in the 2-meter-long carpet to start an intense "Football", only to see the "striker" gradually bypassed the obstacles, step by step, nimbly avoiding the "goalkeeper" blocking, successfully kicked the ball into the goal.
And all the action of this robot dog is actually by two students through their brain waves to remote control, the students as long as the imagination, the brain sends out the "front, back, left, right" instructions, you can easily and freely control the robot dog. The students were able to realize the "thinking" so that the robot dog kicked a soccer ball, is because Tsinghua University recently developed a successful "brain-computer interface" system, which looks like a swim cap of the electrode cap, an amplifier of brain waves and a computer information processor consists of three parts
Not only that, the "brain-computer interface" system can also do brain-controlled telephone dialing, and can even control the students just brought from the dormitory lamps, fans and radios and other home appliances switch. A student put on the electrode cap to do the demonstration, he placed a special telephone dialing screen in front of him, there are 0 to 9 number keys, there are two letters "B" and "C", I will tell him his cell phone number, he looked at the screen, a number was respectively I told him my cell phone number, he looked at the screen, and one by one the numbers were "dialed", and after about a minute, he dialed the cell phone through his own mind, the whole process was not physically manipulated. The lamp, fan and radio were also switched on and off at will under the command of his mind. According to the person in charge, Associate Professor Hong Bo, everyone can do the same operation with ten minutes of training and concentration.
Unlike the neural graft research experiments led by Donahue, the brain-computer interface research at Tsinghua University is non-invasive, requiring only electrodes to be attached to the scalp rather than a chip implanted in the brain.
Professor Gao Shangkai of the institute said the magic of the "brain-computer interface" lies in its ability to establish a direct communication channel between the brain and external devices, which does not need to be accomplished through peripheral neuromuscles, and to obtain commands from the brain to directly control the devices.
Neuroscience and engineering tools have been advancing very rapidly in recent years, and the system developed by Tsinghua is leading the international level in terms of accuracy of information processing.
The brain has no side effects on the human body
Reporter: Does the "brain-computer interface" system have side effects on people?
Gao Shangkai: "Brain-computer interface" is non-invasive, only need to stick the electrodes to the scalp, and do not need to shave off the hair, and do the electrocardiogram of the same reason, there will not be any trauma to the person, because it is only to measure the person's tiny signals, to a certain extent, the person's thoughts to decipher out, rather than to the person to impose any energy. energy on the person.
Reporter: Will the signals be difficult to grasp?
Kai Takagami: There are also people doing invasive methods with implanted electrodes, and the signals are really very clear, but traumatic things are not a good thing after all. The invasive method is like listening to a solo performance, while the non-invasive method is like listening to a symphony, which has to pass through several layers of brain structure before it can be transmitted to the outside world, and the signal is fuzzy and weak, equivalent to one millionth of a dry cell battery, which is really difficult, but we still have a relatively high rate of correctness with this system.
Reporter: What is the next research direction?
Gao Shangkai: We hope to make it more stable, so that it can really be used in patients' rehabilitation training and in brain science research to help neuroscientists understand how the human brain actually processes external information.
Reporter: How much does this equipment cost?
Gao Shangkai: Excluding the computer, it will cost about 5,000 to 6,000 yuan, and mass production will significantly reduce costs. If the domestic medical system for the disabled can be resolved, as a standardized medical device, it will have a good future.
A soccer game controlled by the mind is underway at Tsinghua University