Paralyzed Man Walks with Aid of Mind-Controlled Exoskeleton

Although devices like this are still in the early stage of development, it's not hard to envisage numbers of them being used to quickly and efficiently transport large quantities of building materials around a construction site, for example.

Real-World Exoskeletons

Tetraplegia, also known as quadriplegia, refers to a spinal cord injury above the first (uppermost) thoracic vertebra resulting in the victim being wholly or partially paralyzed in all four limbs. At some stage in the future, medical science may advance to the stage where physicians can repair this sort of injury, but that's probably a long way off. In the shorter term, it may be possible to provide a workable solution using mind-controlled exoskeletons.

As reported in The Lancet Neurology, about four years ago, a former French optician known as Thibault fell and broke his neck, resulting in him becoming a tetraplegic (a.k.a. quadriplegic) and being paralyzed in all four limbs. A team at University of Grenoble Alpes in France set out to get Thibault walking, moving his arms, and manipulating things with his hands by means of a mind-controlled exoskeleton.

Several groups are working on ways in which people with spinal cord injuries can control things using their minds, but these typically involve the invasive technique of embedding an array of incredibly fine electrodes deep into the brain (shades of The Terminal Man). In addition to the possibility of infection, the performance of these electrodes can degrade over time as the body defends itself against their intrusion.

To work around these issues, the team used a semi-invasive approach where two circular sensor devices, each about 5 cm in diameter, replaced portions of the skull on each side of Thibault's head. Each sensor features a grid of 64 electrodes, which press against the membrane that protects the brain. The sensors are then covered by Thibault's skin.

These sensors span the sensorimotor cortex (the area of the brain that controls sensation and motor function). As seen in this video, the resulting signals undergo sophisticated signal processing algorithms that remove noise, determine Thibault's intent, and control the exoskeleton accordingly.

Of course, all of this is still in the early stages. For example, the exoskeleton currently has to be suspended from an overhead harness to prevent Thibault from falling. On the bright side, there is a tremendous amount of related work that is going on in this area that could be brought into play, including artificial intelligence (AI) and the balancing algorithms used by the latest incarnation of the Atlas robot by Boston Dynamics, which is now capable of performing sophisticated acrobatic routines.

The ideal situation would be for the patient to think what he wants to do at a high level of abstraction (e.g., "walk forward," and "raise right arm" -- but not in words, of course), and for the exoskeleton to make it happen while -- at the same time -- taking care of details like maintaining balance and not walking into things or knocking things over.

Hopefully, it won't be too long before we don’t think anything about seeing people wearing self-powered, self-balancing, mind-controlled exoskeletons strolling around leading full and satisfying lives.