Hacking Nerves to Revive Paralyzed Limbs

thats awesome. I'm excited about this line of research.

To me, this is where the good things about science come true.

I suggest an electrical interface between severed nerve bundles. This interface would connect to both bundles and interpret the signals from the brain via tiny electrodes connected to the nerves comming from the brain and then amplify and convey these signals again via tiny electrodes connected to the nerve bundles going to the paralysed muscles. This interface can be planted inside the body along with a long life battery. If the interface goes haywire and it should not if designed carefully, it could be disconnected via remote control. The remote control can also be used to fine tune the interface for smoother muscle working. For instance making signals longer/shorter and/or stronger/weaker.

Does he need an assistant? Is your name IGOR?

you are a rare breed. I can tell already. There are so few around here who make sketches, and you obviously have the artists touch. I insist that you stay around!

I think that we need to first interface with a normally working nerve and monitor the signals that are activated normally, along with the brain cells that activate normally, to activate specific muscles, and map all that out.

The living cell interface of course is the tricky part. We are now getting into nano-electronics, so one might conclude that sensors may one day be able to monitor nerve voltage and current in situ, without detracting from the operation. the problem then would be the wires.

However, if you can make sensors small enough to sit beside individual nerve fibers, why wouldn't you be able to make sensor/actuators as basically repeaters, and that they would connect with nano-wires to other parts on the other side of the injured nerve, and simply pass that signal on to the appropriate nerve.

If the nano-bot-repeaters are able to move, then after sprinkling a few million on each end of the wounded nerves, they can juggle the wires amongst themselves to get the right wiring connected. (here they will need our help. the victim must be instructued to 'move your left leg, and the nano sensors will 'listen' to see which nerves fire, and then they will use our feedback and input current into the lower nerve, and experiment to find the correct nerve to connnect to.)

pretty sci-fi eh! thank you K. Eric Drexler!

There's a lot of high quality neural and device research coming out of Case Western Reserve U, and Schiefer's design seems to be based on a realistic assessment of the issues. The signal levels required to reactivate paralyzed limbs may be unattainable by battery powered devices. The solution in this case is to use an external signal source. Schiefer's interface is to make the nerve fibers accessible to such a source.

Sounds to me like the next step is "standing and walking" software - a program that delivers a coordinated set of signals at the right levels to the independent muscles.

Are these voltage signals of a fixed frequency or are the nerves frequency sensitive?

Next question would be; If the pulses were modulated what type of response would we expect. I know these questions are out in left field , but sometimes we need to think outside the box. This will help so many people if they can get the program off the ground. Wish them all the luck in the world!

...are the nerves frequency sensitive?

I don't know exactly how this applies to the limbs, but nerves or specific brain regions are indeed frequency sensitive - stimulus pulse trains are the usual form of signal for stimulator devices, and the pulse frequency is one of the parameters that makes the difference between therapeutic effects and induction or worsening the symptoms.

For example, DBS devices used to treat parkinsons will "drive rather than suppress tremors" at pulse frequencies below 80 hz, so for therapy, higher pulse frequencies are used. A DBS device at 15 hz pulse frequency induces asynchronous jerky tremor (aka myoclonus). And so on.

A different form of signal "HFAC" is used for nerve conduction block.

I believe the nerves used to recruit muscle groups as in the application we are discussing are physically large (compared with other nerves) and the signals involved are stronger than signals in the brain. So the interface as well as the signal frequency and amplitude has to be tailored to the application.