Interfacing with Neurons to Control Prostheses

Liang Guo et al. are experimenting with the idea of controlling prostheses using the neurons that were damaged in an amputation. They hope to do this by directly interfacing the damaged nerve with the prosthetic device. Using natural or induced regeneration of axons, they believe they can make re-grown axons integrate with a microelectrode array. The ultimate goal for this interface is to establish bi-directional communications between the nerve and the prosthetic, which has been an elusive problem to solve.

They have created a nanofiber-based regenerative scaffold with tunnels through which the proximal stump of a cut axon should grow. Incorporated within the scaffold is a polydimethylsiloxane-based (PDMS-based) conformable microelectrode array. This array is connected to the positive input terminals of an amplifier, and the negative input terminals are connected to the reference electrode. The purpose of the amplifier, which is also incorporated into the scaffold, is to reduce the signal-to-noise ratio in order to facilitate neuron interfacing. The implanted electronics and arrays within the scaffold are connected by PDMS cables, and the I/Os of the electronics are wired to a headstage via subcutaneous wires. Testing has already shown the effectiveness of the electrode channels as well as the biocompatibility of the system, but more tests are necessary to determine the overall effectiveness.

I believe this article was worth sharing in light of the Oscar Pistorius SNBAL. This shows there are people working on controlling prostheses like a normal body part, thus increasing ease of use. Coupled with the growing efficiency of prosthetic devices, the time when artificial body parts perform better than natural ones may be approaching faster than one might imagine.

http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=5709604&tag=1