The "Walk Project", developed by the National Paraplegic Hospital of Toledo and the University of Elche, has managed to design brain interfaces to move robotic exoskeletons
Researchers from the National Hospital for Paraplegics in Toledo and the Miguel Hernández University in Elche (Alicante) have managed to develop brain interfaces to control a robotic exoskeleton that helps people with incomplete spinal cord injury to walk.
The project, called "Walk" was launched in 2019 and could spell the end of wheelchairs. The research is based on the use of exoskeletons -robotic devices that are placed externally on the patient's limbs and allow assistance in any movement- and an interface that records brain activity. According to biomedical engineer Laura Ferrero, who has experimented with this interface, “we try to discern two types of mental state, one related to relaxation and the other to motor imagination. In this way, when a patient imagines that he is moving, we assist him to walk and activate the exoskeleton so that a kind of rehabilitation occurs ».
Imagine that we walk
To do this, it is necessary for the patient to get involved by activating their motor imagination and visualizing that their legs move. "It has been shown that when we imagine a movement, changes occur at the brain level that are very similar to when we make a real movement," says Laura Ferrero. "What we do is see what changes occur at the brain level when a person imagines that movement and, with this, we get the exoskeleton to respond to that imagination," adds this biomedical engineer. In this way, neuroplasticity is favored, a property of the nervous system to generate new neuronal connections and compensate for lost connections.
helmet with electrodes
The "WALK Project" is also based on a helmet equipped with electrodes that record the brain activity of the spinal cord injured person. A helmet, manufactured by the Barcelona company «Neuroelectrics», which allows recording and stimulating neuronal activity. According to the electronic engineer Vicente Quiles, who has also been involved in this project, "a single electrode captures millions of neurons and here it is necessary that the patient who puts on this helmet "has great mental control to imagine his movement without mixing other types of ideas”. In the opinion of this researcher, this type of project could mean the end of traditional wheelchairs.
However, the future of research in this area is directed to other fields: replacing external devices such as the exoskeleton with internal ones in the spinal cord that stimulate it below the level of the injury. It would be about capturing the brain signal, identifying when the person wants to walk and a device placed in the spine could stimulate below the area of the spinal cord injury just at the moment that the desire for movement is detected.