More than 100,000 people in the United States are quadriplegics — meaning they are paralyzed in their arms and legs. This makes them incredibly dependent on others, which can have psychological effects on both them and their caregivers over a long period of time. Those with other disabilities, such as ALS, multiple sclerosis, and muscle dystrophy also require additional assistance in moving around.
Researchers at Duke University have published a study in Scientific Reports that could offer hope to people with disabilities. The scientists were able to create a wheelchair that can be steered across the room by the power of thought alone. While there are wheelchairs for quadriplegics that can be powered by a person's breath, the researchers claim that this new method has greater advantages.
"In some severely disabled people, even blinking is not possible," lead investigator Miguel Nicolelis explained in a press release. "For them, using a wheelchair or device controlled by noninvasive measures like an EEG (electroencephalogram) may not be sufficient. We show clearly that if you have intracranial implants, you get better control of a wheelchair than with noninvasive devices."
The secret behind this incredible technology is an implant that goes into the head and communicates with the wheelchair via a brain-machine interface (BMI). As the brain generates the impulse to move toward a target, hundreds of sensory and motor neurons feed into the implant, which then delivers the command for the wheelchair.
To test this, the researchers gave implants to two rhesus macaques and had them steer a wheelchair toward a bowl of fruit. There was a learning curve, and the monkeys improved with practice.
Over time, it was found, the monkeys' brains adapted in a way that improved the accuracy of their movements.
Previous studies have shown that monkeys can move a robot arm through brain implants, but moving a wheelchair takes this to a new level. Because this study only uses two monkeys, future studies would need to expand on this and assess long-term safety and efficacy before it's tried in humans.
The researchers released a video of the wheelchair in action, and it's pretty amazing:
All images via: Duke University