Since Luigi Galvani discovered in 1789 that muscles react to electrical stimulation, these properties were exploited to create an interface with the nervous system and restore motor and sensory functions deficient. Electrotherapy uses these electrophysiological properties of the nervous system. Although the deficiencies of human sensory-motor system are well known today, they are still too often in a therapeutic impasse. Technological means allow to restore or replace some functions of deficient sensory-motor system.
It has already had great success as in the case of pacemakers to regulate heartbeat, cochlear implants to improve hearing, or even more recently "deep brain" stimulation to minimize Parkinson's disease tremor. Microelectronics and computer technology progress allow to consider new applications to modern neuroprostheses.
And muscles produces movement under the control of the nervous system. Muscles are composed of fibers which convert chemical energy into mechanical energy to produce forces. When a motor neuron sends a nerve impulse, fibers (innervated by the axon) enter into contraction to make a movement. The system consisting of neuron, axon and its muscle fibers is called motor unit.
That's why for someone affected by paraplegia caused by spinal cord injury, it is impossible to recover motor functions. Because of the damaged nervous system. Nevertheless according to researchers of École Polytechnique Fédérale de Lausanne(EPFL) it is maybe possible to join the isolated part of nervous system with the spinal cord in certain conditions such as spinal cord injury must be incomplete (i.e. sensory but not motor function is preserved below the injury or vice versa ). And in order to confirm their hypotheses, they have developed a therapeutic intervention that helped restore a voluntary and adaptive control of rats which had a very severe spinal cord injury that induces a paralysis total and permanent of lower parts. Moreover inorder to stimulate "sleeping" nervous system below the injury researchers injected a "cocktail" of receptor agonists(of serotonin and of dopamine) inorder to increse general level of spinal excitability. And finally they applies electrical stimulation in the spinal cord dorasl side.
Besides they have developped a...