Schneier on Security

Clive Robinson • June 12, 2019 8:47 PM

@ Vas Pup,

How about seven hertz – I guess everybody will respond in same way as ultrasound of the same frequency.

The bandwidth to the brain is different and it ends up in different places and carries the signals in different ways. Which is just one of the reasons “visual prosthesis” by direct electrical stimulation[1] is taking longer than similar technology that has given us “audio prosthesis” via cochlear implants.

Direct electrical stimulation of nerves going into the brain has started to build up a fair amount of scientific data. Amoungst which is information about what went wrong and caused seizures in not just test animals but actual humans.

Such information has been used by those doing other research –such as brain stimulation by magnetic pulse from outside the human head– to reduce the likelyhood of seizures. Thus if you have access to such data working out what is more likely to cause seizures will be somewhat less difficult.

Broadly however if you can find frequencies that are similar to those of the brain at those entry points then you can modulate in a way that can lead to injection locking. From there you can induce various changes in frequency etc.

But a note of caution should be sounded. When someone has an epileptic episode it happens because of what would be considered “cross over” if talking about electrical circuits. Importantly crossover is more prevelent as insulation thickness decreases. In nerves the insulation is in effect the myelin sheath. Thus in individuals where it is thiner they are more likely to be susceptible to crossover. This has for instance been partly demonstrated by the use of plastic surgery and migraine sufferers[2].

But similar issues exist with epilepsy sufferers and there is ongoing research[3] into this.

Of note is that epilepsy is considered by many to in effect be degenerative. That is each seizure will make the next more likely. This accumulator effect my also happen in people with normal myelin around the nerves.

Thus inducing seizures in people is as they oh so politely put it “contra indicated”.

From what I can tell a lot of electrostimulation research is carried out in China, and they may well be the lrading experts. What I do know is that the money to be made in electronic prosthesis is mind boggling. You only have to look at the price of a modern “bluetooth enabled” hearing aid at over two thousand dollars for what in essence is a one dollar area of silicon realestate and the associated MEMS transducers to realise this is going to be a major growth area and way beyond highly profitable.

Thus “doing business” with China is likely to become increasingly necessary for “Health Care” in the USA. Something those of an age where electronic prosthesis is becoming important to being able to function in society should consider somewhat thoughtfully. We talk of “locked in syndrome” (pseudocoma) where a person is aware but only capable of communicating with others by small vertical eye movments or partial blinking. Due to the way the first world has shifted to be reliant on electronic communications through Smart Devices and the like we have to ask ourselves what would happen if we were aware and rather than not being able to send communications out, could not receive incoming communications… Personally I think limitations in communications in either direction is not something people would want.

After all it’s not difficult to imagine being incapable of moving in the middle of a vast corn field in the pitch dark. Where no matter how hard you shout you don’t even hear an echo, just the static like noise caused by dry stalks in a gental breaze. It’s a kind of stock meme for horror films, but imagine it for real as your senses age, what price would you pay to not be in that place?

But then again there is a flip side, as with most technology it’s “dual use” and “agnostic to use”. We’ve seen virtual world artifacts overlay the real world, and work with games on mobile phones where Nintendo charecters can be hunted.

But consider what price would you pay to have virtual reality overlay it’s self on the real world inside your head?

That’s where the real money is going to be in a few more years as electronic stimulation of nerves in prosthetics improves. And sadly almost the first use for it will be as it was with mobile phones “Girls, Gambling and Games”, then of course “kitten videos” with 24Hour direct to mind advertising to follow. Such is the human condition, we always bite the apple and get thrown out the garden.

[1] This article gives you some background on “visual prosthesis” and similar areas of research,

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4329712/

[2] https://www.sciencedaily.com/releases/2014/11/141103113557.htm

[3] https://www.europeanreview.org/article/11682