Robotic appendages that do the work of lost limbs are the rock stars of neuroscience research. New ways to control a robotic arm, create software, and accomplish every day tasks with machine learning are hot topics of study in may labs and hospitals. Exciting research from the University of Minnesota was recently published and cold be a major breakthrough for some patients. Whether they have lost a limb, have paralysis or some neurodegenerative disease, the team in Minnesota might have just made it easier to use a patient’s mind to control a robotic arm.
Using electroencephalography (EEG) technology, researchers at the University of Minnesota’s biomedical engineering department have developed a non-invasive method to detect brain waves that can then direct the robotic arm. Using a cap that is fitted with electrodes that detect EEG patterns through the scalp, with no incision or implants, the team demonstrated that patients can turn their thoughts into action and control the machine arm. A computer interface was developed along with the cap to complete the circuit from brain to limb.
Bin He, a University of Minnesota biomedical engineering professor and lead researcher on the study said in a press release,“This is the first time in the world that people can operate a robotic arm to reach and grasp objects in a complex 3D environment using only their thoughts without a brain implant. Just by imagining moving their arms, they were able to move the robotic arm.”
The trial was carried out with eight healthy human subjects. During individual sessions, the study volunteers would wear the cap and gradually learn how to imagine tasks. The sessions started with simply using thoughts and visualization to control a cursor on a computer screen. Gradually the tasks became more complex, with participants having to control the motions of a robotic arm in a 3D environment. Eventually, they were able to get the arm to reach out, touch, grasp and pick up objects, and even place them in locations like shelves and tables. All of this was accomplished simply by thinking about the muscular movements necessary to complete the task, but not actually moving their own arms. When picking up objects the success rate was just above 80% and the participants showed roughly a 70% success rate at moving an object from a table to a shelf.
Professor He is no stranger to EEG technology. The robotic arm research grew out of earlier research that he was involved in three years ago. In that experiment, subjects were tasked with flying a small quadcopter using similar caps and EEG readings. The technology of the brain-computer interface is key in this kind of research and He has the experience in this area. The motor cortex is the part of the brain responsible for controlling movement. When someone moves their arm, or even just imagines their arm moving, neurons in that area fire and create electrical currents that can be picked by the EEG cap. He demonstrated this in his prior research using functional MRI studies, so he knew where to begin.
He and his team hope to improve the interface software to see how it might work with paralyzed patients or others with movement disorders. Take a look at the video to learn more about this technology and what it could mean for assistive devices for neurological conditions.