# Creating a scientifically semi-valid super-soldier, part 2: nervous system

This question is about a complete rebuild of the nervous system. The question as proposed here: Improving human reaction time has only answers concerning upgrading current nervous system.

One of the common tropes of super-soldiers is a faster brain so you can see things in slow-motion and extremely fast reflexes, often dozens of times faster than what normal human nerves would be capable off. But how would you go about making a nervous system that is actually capable of such feats?

For this question, I'm assuming important secondary nerve functions can be performed by glands or "normal" nerve-ends that are attached to the super-nervous system at intervals.

I'm also asking for a biological nervous system that the body can maintain and repair when necessary. For clarity: These soldiers would supplement robotic and cyberneticly enhanced soldiers mostly as canonfodder. The goal would be to split the resource requirement between more rare materials+fuel sources and humanoids that use biological compounds and food instead of fuel.

For the nerves there's two things that can improve their ability. First is thinner nerves, as that would allow more muslce-fibers to be directly actuated by a nerve, second is a faster signal propogation.

I'm thinking about biological optical fibers, but don't know if that's possible. Alternatives could be extremely long myelin sheeths, but I'm not sure if those would be possible or what kind of speed you would gain from it. What's left would be biological electrical wires.

Does anyone have an idea what would be a feasible soft-science nerve? Preferably with the potential propogationspeed of a signal added.

• The problem with "seeing things in slow motion" -- which is nonsese, the super-soldier will still see 1 second of life in 1 second of time; I suppose that you mean having a higher threshold of motion blur, so that for example the supersoldier would see each frame of a cinema movie individually -- is not the processing speed of the brain, but rather the limited bandwidth available on the optical nerve, and the speed of recovery of the light receptors in the eye. – AlexP Mar 19 '18 at 11:46
• Possible duplicate of Improving human reaction time – Frostfyre Mar 19 '18 at 13:06
• @AlexP I know that slow-motion is a bullshit trope. I've read about instances where your average human will start seeing in slowmotion in extreme situations. For example a police officer in a shootout who was wondering why tomatosoup cans were slowly dropping to the ground as if they were flying through honey, only to realize later that his partner was firing a shotgun and that the soupcans were actually shotgun shells. Which shows exactly the drawback of using the brain's slowmotion settings: Your brain shortcirquits thinkingprocesses so that you can do things faster, but you'll make mistakes – Demigan Mar 19 '18 at 15:11
• That's called perceptual time dilation. It's a psychological rather than a physiological effect. – AlexP Mar 19 '18 at 16:36
• Thicker, not thinner nerves would get signals travel faster. – Alexander Mar 19 '18 at 16:47

A possible soft science answer may be to use the skeletal structure modified with the same crystalline structure on the surface of the bones found in the scales of a butterfly wing that would use bio-luminescent glands to transfer data to muscles without the normally slow neuro-transmitters in the normal nervous system. the biological nature of the scales would mean that they could be self-regenerating.

• Not sure if this has potential. Why would you place this on the Skeleton? Wouldn't they work better as nerves running through your body? And from what I know about them, these structures only let through blue light (unless made wet with Alcohol for example, then it becomes green), and if you look from a different angle the colour changes. Wouldn't that have a large effect on the signals? – Demigan Mar 22 '18 at 9:17
• The use of the skeletal structure appeared to meet your request for a secondary nervous system to transfer information and the bio-crystals should be able to be tuned like a lens to transmit at whatever frequency you would set..Incorporating the crystals into the skeletons would reduce the possibility for damage in a battle scenario – Eric Vanblaricom Mar 22 '18 at 14:50

You can always go down the synthetic human path. A brain made from billions of tiny individual machines that for a network with each other. The connections are non existent because they can communicate trough subspace or some shit. Each such machine would be equivalent to a processor from our time but many times smaller, the size of a neuron and there will be billions of them. They can act as any part of a computer like storage, processor etc. One problem would be the high energy demands of such a rig or the heat from it. Heat resistant synthetic neurons and powered by a fusion reactor in the heart somewhere. The excess heat could be use as a weapon maybe. Firebending synthetic super-soldiers. That would be cool.

• I'll stress that it needs to be a biological creature, I've expanded my question to better reflect it, – Demigan Mar 19 '18 at 15:17

Per Hypertextbook nerve impulse speeds vary between 0.61 m/s (pain), 76 m/s (touch), and 191 m/s (muscle firing). It also, in the case of reflex, can fire multiple signals and register-but-ignore the late arriving ones.

If you were to thread the nervous system with fibers doped with some material at the active sites that converted sodium and potassium surges to an electrical impulse, then had an additional diode-like material to convert that electrical impulse to light, passed the impulse down the fiber, then repeated that process in reverse to stimulate either muscles are excite a nerve cluster, the signal speed would be much closer to the speed of light (300,000,000 m/s). For a 2 meter tall person you would only be shaving 0.01 seconds ( $2 meters \over 200 m/s$) off reaction time.

I have an old equation for aiming time. I don't remember the origin, but it was measured by asking subjects to click on a circle with a mouse. $t = B + a \log({2\pi\over D})$ where D is target diameter in meters and B and a are experimentally determined values. B = 0.5 seconds and a = 0.45 seconds in the test subjects. There is an initial reaction time, but then your brain is engaged in a feedback loop moving towards the target, assessing progress, and moving again.

You can shave the 'a' try-assess-correct loop (0.45 seconds) by training and building muscle memory. However, this is available to normal humans and super humans both.

If I remember correctly the initial reaction time 'B' did vary between subjects. There are studies indicating that stimulants could drop initial reaction time by 100 milliseconds (20%). Some combination of stimulants and focus enhancers may be able to achieve greater effect. But overclocking reaction time results in the nervous stereotype of someone overstimulated.

• Interesting, I would like some more information about speeding up the brain as well. These articles cite: ncbi.nlm.nih.gov/pubmed/9572238 du.ahk.nl/people/carolien/papers/reactiontime.htm, connections between neurons go slower and could be sped up. If the velocity of a reaction really is 191m/s including synaptic connections, it would mean that a single neuron in a single-synaptic sensor-motor neuron feedbackloop would already take 99,76% of the total latency on itself. Dendrites might be a problem (0,5m/s), and it seems impossible to find synaptic gap velocities. – Demigan Mar 27 '18 at 18:19
• I read that synaptic gap velocities are no greater than normal diffusion, which is about 1x10-9 meters-squared per second for Calcium. Converting that into meters/second requires getting the derivative of $A = 4 \pi r^2$ -> $dA = 8 \pi r dr$ ... $dr = {dA \over (8 \pi r)}$. For a synaptic gap (r) of 20 nanometers and a diffusion rate (dA) of 1x10-9 m2/s, then dr = 0.0119 m/s, but that would be instantaneous velocity at the other end of the gap. Average velocity across the gap would be half that radius and 0.0238 m/s. – James McLellan Mar 28 '18 at 1:04

Perhaps a distributed nervous system may help, with individual automatic functions in nerve clusters directly adjacent (or at least closer) to organs they need to control. Cuts down distance at least.

Another interesting thing is using a similar brain architecture to intelligent birds. Birds like crows and parrots pack a lot of brainpower into a very small brain, and the way they do this is by having clusters of tiny neurons (which take up little space but can't bridge large distances) connected by larger neurons to link the clusters together. Expand that structure into a brain the size of a human's and you could leverage a phenomenal amount of processing power. Not sure how well that would affect raw reaction times, but it might allow for faster prediction of potential circumstances allowing for reactions to happen before an actual event has taken place.