Potential downsides to a super-soldier heart-rate safety mechanism

Question

Setting: Earth, no more than a century in the future.

Premise: Certain US soldiers volunteer to receive genetic modifications that grant increased strength, endurance, and healing capabilities. Most of these capabilities are only technically superhuman--they are slightly above what a normal human can achieve. They can't lift cars or punch holes in steel bulkheads.

The greatest advancement is their endurance: an engineered soldier can theoretically run at a full sprint indefinitely, given a constant supply of calories and water.

Problem 1: The soldiers tend to push themselves beyond their new physical limitations, as they no longer experience the fatigue of a baseline human during exertion, and they do not have evolved instincts for their new capabilities. As a result, an engineered soldier can accidentally raise their heart rate and blood pressure to the point where they'll suffer instant death due to cascading burst blood vessels in their brain.

Solution: The engineered features include a pea-sized gland within the soldier's brain, which will create phantom physical sensations to warn the soldier when they begin to approach their limit.

If they ignore these sensations (like a buzzing cell-phone over their heart) and get too close to the fatal limit, the gland will instantly render the soldier unconscious, and gradually slow their heart.

Question: What are the potential flaws in the warning/killswitch gland? More specifically, what are the potential flaws in a safety feature which will instantly knock a soldier unconscious in a situation where they would otherwise have a very good chance of dying (>90%)?

Are there any obvious ways that an enemy force could exploit this killswitch to their advantage?

[Edit]Problem 2: Why not use the gland to mimic the fatigue sensation? The genetic engineering technology is still relatively new, and geneticists are able to create very straightforward sensations (ie, a given patch of skin, of a given diameter, will feel like it's buzzing). More abstract sensations, like fatigue, vary wildly from person to person (in terms of brain chemistry), so they've not yet developed a safe catch-all.

A second issue with mimicking the fatigue sensation is that soldiers are all trained to push past it as part of basic training (not just in this future setting, but in reality). The difference is that non-engineered--but otherwise healthy and fit--soldiers will typically reach muscle-failure before hitting any fatal heart rate or blood pressure.

Answer 1

I would expect a better safety mechanism. Rendering a soldier unconscious at any time other than for immediate medical attention (say by a trained medic or other medical personnel) is a HUGE risk and would be a bad idea.

If the soldier dies, they can't be captured and interrogated, and being a 'super-soldier' they can take a lot of abuse as well as teach the enemy a lot.

If they pass out during extreme exertion with a 'kill' switch then you would be endangering any mission that they happen to be participating in.

So one low tech way to train them to stop or slow down before going over the edge would be some Pavlovian training. During actual training missions have the soldiers wired up to monitor their life signs. They all need to wear shock collars (like dogs). Then push them to their limits, with 'incentives to push past them. When their internal 'buzzing' has gone off for 'x' time (and still within safety limits) shock every soldier who hasn't backed off to 'recover'.

Eventually they learn their 'new' limits. Then it is up to the soldier to 'take care of themselves'.

Answer 2

Field test

Target: Group of soldiers running full tilt to reach an objective.

Tactic: Adrenaline rush to trigger shutdown by rapidly pushing heart rate over threshold, minimal shock required. Low yield explosive detonated nearby will be sufficient.

Result: Target group go into automatic shutdown and are trivially captured.

Conclusion: I feel your new technology has a flaw and requires some reworking before combat use.

Answer 3

What are the potential flaws in the warning/killswitch gland? More specifically, what are the potential flaws in a safety feature which will instantly knock a soldier unconscious in a situation where they would otherwise have a very good chance of dying (>90%)?

Two obvious flaws are guaranteed death if the kill switch triggers in a life-or-death situation, or guaranteed death or capture if the enemy discovers a way to exploit the kill switch. That kind of solution is obviously defective and unsuitable for any application at all.

The greatest advancement is their endurance: an engineered soldier can theoretically run at a full sprint indefinitely, given a constant supply of calories and water.

Muscle fatigue is partially caused by loss of biochemical substrates and build up of metabolites within the muscle - perhaps the solution is to cut down on the efficiency of the modifications that addressed those issues so that physical fatigue still occurs under above-average exertion/stress?

Problem 1: The soldiers tend to push themselves beyond their new physical limitations, as they no longer experience the fatigue of a baseline human during exertion

There may be a problem zero: heart failure or stroke through overexertion, same as occurs within normal human beings. Even though you almost certainly beefed up the super-soldier's heart muscle along with the remainder of their physiology, this will still hold true.

As a result, an engineered soldier can accidentally raise their heart rate and blood pressure to the point where they'll suffer instant death due to cascading burst blood vessels in their brain.

How about partially or completely separating the body's and the brain's circulation and having a secondary system with its' own heart to supply the latter? This could additionally serve as a protective measure against brain damage / death in the event your super-soldier's primary heart fails (or is damaged in combat), as well as regulate oxygen supply to the brain so that your super-soldier would not be under risk of light-headedness or loss of consciousness if their body is consuming too much oxygen.

Answer 4

So, basically what you are saying is that you've done 2 different modifications:

1. slightly meta-human strength
2. turned off sensations of fatigue/exhaustion or at least gave the soldiers a mental program to temporarily turn off sensations of fatigue/exhaustion

(otherwise you would never get your 'infinite endurance until drops dead' feature).

I'd say the main issue is point (2), since I assume 'slightly meta-human strength' means a bit more muscles than usual. The new strength would then still be covered by the regular endurance/exhaustion mechanism. If 'slightly meta-human strength' means reworking the entire biology of muscles and skeleton and hormones with (2) being a (welcome) side-effect, then I'd say you have enough biology knowledge to also adjust the exhaustion mechanism.

So, you have created a modification that lets a soldier forget / ignore exhaustion. I'd say: teach your soldiers to every now and then take a check of their body, give them a pulsometer that signals them when their heart-rate or blood pressure exceeds a certain rate, and then let the soldier decide what to do...

And unless you've also turned off pain (NOT a good idea), that is another way of informing your soldier that he should better rest his body before landing himself in hospital.

Answer 5

There are three major issues. The first is a matter of modeling. How does this gland know what "too much" is? Each body is different and constantly changing. It's hard to know where the limit actually is, unless you hit it. A binary cutoff like this would limit soldiers to their modeled capacity. This is bad news for soldiers. Soldiers are not taught to get near some artificial line in the sand drawn back at base. They are taught to use everything in their disposal to accomplish a mission. They are not going to like being told "you can't use the entirety of your capabilities, even though we gave them to you." Its just now how the military works. A military that works that way is defeated by a military that is willing to go the last mile.

The second issue is one of a new weakness. Enemy soldiers now know that all they have to do is confuse the sensors of this new gland to convince it the heartrate is too high, and their opponent will pass out. New weakpoints like that are also frowned upon by soldiers.

Finally, the unconcious mechanism is not ideal. In some situations, such as when they are at risk of capture, going unconcious is worse than a death sentence. In other situations, where everything is on the line, passing out can be a death sentence. Only now instead of having a potential death a few moments from now, from bleeding out, you have a guaranteed death because the system killed you. Again, not popular for soldiers.

I would recommend adjusting the gland to operate more like our built in safety mechanisms work. We have dozens of reflexes which protect us, but may be non-ideal in some situations. We have the capability to suppress those reflexes consciously, to get a job done. Thus the safeguard protects us in the easy cases, but we can bypass the safeguards when needed. In day to day activity, or training, the solder would likely operate with full safeguards intact, including passing out. In a combat situation, they may suppress some of the safeguards, but perhaps keep some of the ones which are less troublesome. In an extra high stress combat situation, they may consciously turn off all safeguards to get a job done.

I would also recommend a middle layer in the safeguards. At first, it may provide a sensory signal. If the solder continues to work too hard, it may start pushing back against the soldier, trying to decrease how much they are overworking. If the soldier pushes past that (which they should be allowed to), then drastic measures like unconsciousness may be useful. And of course, the soldier should be able to suppress that.