How it works (Imagining Thought-Controlled Movements for Humans- The New York Times)
This ability to make machines that respond to thoughts rests on the fundamental properties of the nervous system. Our brains plan every movement our body carries out fractions of seconds before actual movements occur.
These plans are in the form of neural patterns (electrical patterns) which arise from neurons (cells) that fire at the same time, from different sections of the brain. The plans are sent to spinal cord neurons that are connected directly to muscles. Only then are movements carried out.
To establish the link between brains and machines, researchers implant electrodes into sections of the brain that produce the motor plans. These electrodes would extract raw electrical signals from the brain that can be translated mathematically into signals that computers and robots understand.
The following section gives a brief summary of the experiment conducted by Dr Miguel Nicolelis.
Description of the experiment (Monkeys Control Robotic Arm With Brain Implants-Washington Post)
First, patches of skull from the two monkeys were removed to expose the outer surface of their brains, after which microelectrodes were implanted into their brains. The monkeys thus had wires protruding from their heads which connected them to a computer and from there, to a large robotic arm.
Next the monkeys were trained to use a joystick to move the robot arm. They were able to make the arm reach and grasp for objects and also vary their own grip on the joystick to adjust the robotic hand’s grip strength.
As the monkeys trained, the computer tracked the patterns of neural activity in their brains. It soon figured out the patterns linked to specific actions such as “reach” and “grasp”.
The joystick was then unplugged so that the robotic arm’s movements were controlled solely by the monkey’s brain activity. The computer was effectively acting as an interpreter by decoding the brain signals and sending the appropriate instructions to the robotic arm.
The next step (Thought-controlled robotic arm may work in people -New Zealand Herald)
Following the success of Dr Nicolelis’s experiments with monkeys, the next step would naturally be to apply it to humans. However the experiments described above were conducted when the monkey’s skulls were open to expose their brains, which is definitely not something that can be done to humans just in the name of research.
Instead, Dr Nicolelis and his colleagues have been able to work on patients with Parkinson’s disease who had to undergo brain surgery anyway. They were given 5 minutes with each patient to conduct their research during which the patients were given a video game to play while the implanted electrodes sent their signals from within the brain to a computer. The computer then analyzed the signals and correlated them with the hand movements used during the video games.
Given the fact that their time with each patient was very limited, they could only record the subjects’ brain activity and then teach the robot arm to respond to the different brain patterns in the laboratory. Thus as yet there have been no successful experiments with humans controlling the robotic arm with just their thoughts. However Dr Nicolelis and other researchers in this field are optimistic that given a few more years, thought-controlled robotics can be used by humans.
Potential applications and benefits
The most obvious potential application for this technology would be in developing robotic limbs for quadriplegics. This is especially significant because earlier experiments in this field used peripheral nerves instead of brain cells which cannot be applied to people with spinal-cord injuries or degenerative nerve diseases.
With thought-controlled robotics, quadriplegics would be able to operate machines or tools with their own thoughts as naturally as others do with their hands. They would no longer have to depend on others for simple everyday actions such as brushing their teeth or switching on the television.
Also this technology might even allow some paralyzed people to move their own arms and or legs again by transmitting the brain signals directly to their muscles instead of to a robotic limb.
Other applications of thought-controlled robotics for the paralyzed could include a thought controlled electric wheelchair or computer keyboard. These applications would give them increased freedom of movement and also the ability to communicate.
Lastly these brain implants could also allow scientists or soldiers to control hands-free robots that could perform tasks in harsh environments or in war zones.
Conclusion
It is clear that the potential benefits of thought-controlled robotics are large, not only for the paralyzed but also in the area of science and defence technology among others. Although the current level of technology is limited to monkeys, with the scientists poised to begin human trials, it is likely that thought-controlled robotics for humans will be available within the span of the next few years.
Additional References:
Duke News Service: Monkeys Control A Robot Arm Via Brain Signals – Nov 15, 2000 World Wide Web:
TIME.com: Robo-Monkey’s Reward – Oct. 27, 2003 World Wide Web: