Prosthetic Arm Technology That Detects Spinal Nerve Signals

Colin Neff

4/24/17

PSYC 465-002

            I read the article “Prosthetic Arm Technology That Detects Spinal Nerve Signals” by Colin Smith from Imperial College London outlining the prosthetics research conducted by Dr. Dario Farina. In this reading, the author reviews major achievements recently made in the field of prosthetics. Dr. Farina recently tested the effectiveness of prosthetic arms which are activated by signals from the peripheral nervous system, rather than by activity in the remaining muscles of the shoulder or arm. This research is valuable because the current muscle activated prosthetics are difficult to program and operate as these remnant muscles are often damaged. As a result, prosthetic users can only perform basic motions, while operations such as grasping or wrist movement are less feasible. By re-routing components of the peripheral nervous system to the pectoral muscle or bicep (based on the site of amputation), Dr. Farina was able to make some progress in mainstreaming this technology. After some physiotherapy, patients were able to move the elbow joint of the prosthetic and rotate the wrist; both of these operations are nearly impossible with the classic muscle-activated prosthetic. In order to make this technology possible, researchers had to decode and map information sent from the previously re-routed nerve cells. This information was then compared to that of a healthy individuals nerve cells so that researchers could produce a fuller range of motion. Finally, specific signals sent from motor neurons were encoded as commands for specific movements. Researchers believe that by continuing to encode these motor neuron signals, they will eventually be able to produce seamless prosthetic movement nearly identical to that of an individual with the corresponding limb.

            I find this research extremely interesting as it provides a new and potentially much more effective solution to amputees than an already amazing prosthetic method. This ground-breaking research suggests that individuals with prosthetics will eventually suffer little to no limitations as a result of their condition. Furthermore, it eludes to potentially major advances in robotics, as a more direct link has now been made between the human brain and an artificial limb. This topic strongly relates to our class discussion on the peripheral nervous system. The researcher is evidently forming a connection between the somatic nervous system, which includes the motor neurons that the prosthetic is responding to, and is responsible for control skeletal muscles. This is made clear in the article by the fact that participants must essentially be trained to think as though they are controlling a phantom arm. One aspect of this research which I would like to hear more about in the future is this systems influence on the autonomic nervous system. While the advances made in this study were more than enough, I would be interested to see if reflexive movement could eventually be encode in these prosthetics, as reflexes originate in the spinal cord where the nerve cells are routed from. Though this question is likely far from an immediate concern, as much work needs to be done on the prosthetics interaction with the somatic nervous system, there does seem to be potential for a fully functioning limb as a result of this research.

http://neurosciencenews.com/spinal-nerve-signals-prosthetic-arm-6070/