MOTOR IMAGERY OF LOWER LIMBS MOVEMENTS TO CONTROL BRAIN-COMPUTER INTERFACE

The review is dedicated to the problem of the use of brain-computer interface (BCI) systems controlled by the imagination of lower limb movements and their application in clinical practice. The research on this topic is significantly scarcer than the research of BCI controlled by the imagination of upper limb movements, which is partly due to methodological difficulties. The review describes various modifications of BCI; most studies are concerned with the recovery of the walking function, while other studies explore the movements in the ankle joint. To achieve the recovery of locomotion, BCI is often controlled through imagining walking, which leads to an avatar moving in the virtual space. In some studies, motor imagery is accompanied by functional electric stimulation to activate the muscles that ensure the implementation of the imaginary movement, and/or by activation of external mechanical devices (orthoses, exoskeleton). Finally, some studies offer fundamentally new integrative approaches, for example, BCI controlled by the imagination of hand movements, where the signal triggers the movement of the avatar's legs or orthoses, accompanied by tactile stimulation of the forearm in the rhythm of walking. No studies of the recovery of the lower limb functions with the help of BCI performed in Russia were identified in the literature.