A primate with spinal damage has regained control of its paralyzed right leg after scientists successfully implant a neuroprosthetic interface, creating a wireless bridge between the brain and spine. Matthew Stock reports.
This rhesus monkey has a partial spinal cord lesion, which paralysed its right leg. But a neuroprosthetic implant has allowed the primate to walk again. The brain-to-spine interface decodes motor intention from brain signals, then relays this to the spinal cord, bypassing the injury. Small electrical pulses stimulate neural pathways to trigger specific muscles on the legs - restoring locomotion in real-time. SOUNDBITE (English) GREGOIRE COURTINE, EPFL NEUROSCIENTIST, SAYING: "We inserted one of the electrodes in the small region of the cortex that controls the leg. And send the information from all the neurone we recorded to a computer that decoded the motor intention of the primates based on this signal. This means the extension or flexion movement of the leg. And the computer then sends this information to the implantable stimulator that has the capacity to deliver stimulation at the correct location with the correct timing in order to reproduce the intended extension or flexion movement of the leg." The research was led by the Swiss Federal Institute of Technology, alongside international collaborators. Other neuroprosthetics have previously given amputees basic control over prosthetics. And in 2012 the team here were able to stimulate a paralysed rat's muscles to help it walk. This development takes spinal cord stimulation to a new level. SOUNDBITE (English) JOCELYNE BLOCH, NEUROSURGEON AT LAUSANNE UNIVERSITY HOSPITAL (CHUV), SAYING: "To make the link between the decoding of the brain and the stimulation of the spinal cord, and to make this communication exist - this is completely new." A clinical study is now underway in Switzerland to access the feasibility of the implant in helping humans with spinal cord injury. The research is published in the scientific journal Nature.