The use of an exoskeleton that enables independent movement while providing tactile feedback has been hailed as a great step forward for people suffering from paralysis. So far, this invention which is part of the Walk Again Project has enabled eight paralysed patients to regain sensation and movement in previously paralysed limbs. The thought-controlled exoskeleton was developed at the Duke University in North Carolina and, since September 2013, has been used by the project team, headed up by Miguel Nicolelis, to help people gain regain control over their legs.
The robotic device encases the wearer’s limbs converting brain signals into movement, and seems to have the ability to ‘reawaken’ the nervous system by feeding back sensory information to the wearer. This was proven following reassessment after 1 year’s training with the exoskeleton, where Nicolelis found that all 8 wearers exhibited regained sensation and were able to move muscles in their paralysed limbs. This proved very emotional for both the patients and the project team as nobody expected to see such a high level of recovery.
Nicolelis explained that when the spinal cord is injured, damage can also occur between the body and the brain, meaning that the person is unable to move or feel parts of their body. If a few spinal nerves are left undamaged, it is possible to recover control over their legs, although this often takes years of treatment. However, when the spinal nerves are severed, there is no feeling below the injury and there is no chance of recovery.
The exoskeleton was developed by a team of 156 people and is able to read the wearer’s brain activity and to translate the activity patterns of the wearer’s brain into an electrical signal that moves the exoskeleton’s legs, thus enabling the wearer to walk. But more than this, the exoskeleton provides tactile feedback to the wearer, as artificial skin which lines the sole of each foot sends signals to their forearm which is still able to feel sensations. However, the biggest surprise of the whole project was that all eight volunteers showed signs of functional recovery, with everyone being able to move muscles in their legs.
Despite this, the mind-controlled Exoskeleton is still a prototype and the project are aiming to develop a more slim-line and affordable version.