Sleeveless moves robot's hand with the mind

The sleeveless monkey controls the robot with the mind. A neuroscience team at the University of Chicago showed people who underwent amputation of the arm could learn to control the robotic arm through electrodes implanted in the brain.

Scientists report changes on both sides of the brain used to control limbs that have been amputated. Both areas of the brain create new connections to learn to control the device, even years after amputees.

Tinuku Sleeveless moves robot's hand with the mind

"This is a new aspect, seeing that people who are chronically and long-term amputees can learn to control the limbs of robotics," says Nicho Hatsopoulos, a biologist at the University of Chicago.

"But what's also interesting is the brain's plasticity from long-term exposure and see what happens to network connectivity as they learn to control the device," Hatsopoulos said.

Previous experiments have shown how a paralyzed human patient can move a robotic limb through a brain machine interface. The new study is one of the first to test device via amputation.

The researchers worked with three rhesus monkeys who suffered injuries at a young age and where the arms had to be amputated to save them. Each occurred 4, 9 and 10 years ago. The remaining limbs were not amputated for research purposes.

The team planted electrodes on two monkeys with an arrangement on opposite or contralateral side of the brain to the amputated limbs. In the third animal, the electrode is implanted on the same side or ipsilateral to the amputated limb.

The monkey is then trained to move the robot arm and hold the ball only by using the mind. Records of neuron activity where electrodes are placed and statistical models count neurons connected to each other before experimentation, during training and after monkeys master activity.

The relationship between neurons on the contralateral side is rare before exercise, most likely because it has not been used for long-term related function. But as the exercise progresses, the connection becomes stronger and denser in the area used for grasping.

While ipsilateral compositions show solid connections at the beginning of the experiment, but the researchers saw something interesting during the course of training that shortened connections and thinning tissue before rebuilding a dense new network.

"Connection is shed as the animal tries to learn a new task, because there is already a network that controls other behaviors," says Balasubramanian, a biologist at the University of Chicago.

"But after a few days began to rebuild a new network that can control the limbs and neuroprostis intact," said Balasubramanian.

The research team plans to continue the work by combining research by other teams to equip the prosthetic neuro limb with sensory feedback for touch and proprioception which is a sense in which the limbs are in space. The team reports the results to Nature Communications.

"That's how we can start creating responsive neuro-prostatic limbs, when people can move them and get a natural sensation through the brain machine interface," Hatsopoulos said.