20090926

Sensory Prostheses and Nonlethal Police Methods

Not too long ago (seems like ages, but some of us are still serving community service for unauthorized protest), 20 delegates from the self appointed most-powerful nations descended on Pittsburgh. I'm not... exactly sure what, if anything was accomplished in this G-20 meeting, besides raining a whole hell of nuisance on the Pittsburgh community. I'm not going to go into the details of the general awfulness and terror that ensued, you can find that on elsewhere. Instead I will focus on the intersection of neuroscience, non-lethal police methods, and sensory prosthetics.

Police arrived in town with all manner of goodies and anticipating war. These included the usual pepper aerosol bombs and rubber coated bullets, but also the technologically sophisticated Long Range Acoustic Device (LRAD).

The number of technologically sophisticated devices designed for non-lethal control methods is increasing, and research into the human nervous system both guides the design of such weapons, and also provides clues about how to guard against them.

The principle use of nonlethal weapons is to achieve a tactical advantage and a measure of control without causing permanent injury. I will group said weapons loosely into three categories : painless immobilizing techniques, methods of inducing pain, and advanced methods of sensory incapacitation. The first two are familiar and historical. Advanced, painless, methods of sensory incapacitation is a subject of ongoing research.

We can have lots of fun with painless immobilization techniques ( handcuffs ? rope ? nets ? barricades ? paintballs filled with glue ? foam bombs ? ), and have most likely not exhausted this category. We can also inflict pain fairly easily ( blunt force, tasers, pain stimulating chemicals in various delivery systems, bashing people over the head (these also seem to have the nasty problem of occasionally just killing people)). We are only beginning to hack the sensory systems to achieve immobilization in the absence of either pain or physical restraint.

The LRAD falls somewhere on the boundary between sensory hacking and pain induction. With respect to sensory stimuli, the LRAD is quite simple. It is very, very, loud. It is so loud that it will almost certainly irreversibly damage hearing. Its primary mechanism of action to to simply cause extreme pain in the more sensitive components of the human auditory system, and it is still a crude device.

High intensity strobe weapons are a bit more curious. They generally do not exceed the luminance tolerance of the eye, and so pain is not their main effect. Instead, they overwhelm and incapacitate the visual system, allegedly causing nausea and vomiting in some subjects. This strobe light incapacitating ray may well be the first true sensory hacking weapon.

How does it work ? As far as I know, that information is not publicly available, but I can speculate. The lights change faster than the human visual system can adapt. In fact, they change so quickly that the computational architecture of the retina and primary visual cortex ceases to perform its usual computation. As a result, the visual system is overwhelmed by artifacts of the computational structure : at the right frequencies, vision breaks down into noise and simple geometric shapes. Given a particularly unpredictable and destabilizing visual stimulus, the discrepancy between vision and the other senses becomes large. This lack of sensory alignment can cause nausea of a form not entirely dissimilar to motion sickness.

Can we conceive of other such weapons in other sensory modalities ? Certainly touch and taste are inaccessible remotely. This leaves audition and olfaction. Frankly I can't think of any way to hack olfaction besides a really terrible smell (thank you Sea Shepard). LRAD is a very crude hack of the auditory system, and barely counts. Perhaps a loud signal mimicing the statistics of natural speech can block communication in crowd control situations ? Perhaps an as yet undiscovered auditory analog of the flicker hallucination effect exists ? Or, perhaps a combination of auditory and visual stimulation in a synchronized fashion can geometrically amplify the efficacy of the strobe light incapacitating ray.

You don't think I was just sitting at home thinking of new technologies for hurting people while my friends were getting gassed, do you ? No, for many incapacitating agents there exist countermeasures. Sensory prosthetic systems can act as a general purpose perceptual filter, removing noxious stimuli and passing only useful information on to the brain. We are not yet in the age of augmented reality of this sophistication, but military research may drive us there.

A heads-up display with expanded sensitivity to wavelengths outside the visible spectrum could conceivably dodge the jamming effects of the strobe-nausea ray. By a combination of shifting to wavelengths that are not being jammed, and filtering out the flickering signal, we can reconstruct a useful visual scene. In short, Mr. La Forge is probably immune to strobe weapons.

An auditory prosthesis ( e.g. hearing aid ) can be turned off to prevent pass-through of the LRAD. Now, an auditory prosthesis attached to a digital filtering device may be able to pass through some sounds while still blocking the LRAD channel. At the very least, the prosthesis could clamp the audio to a non-painful level, and return to standard pass-through in-between LRAD bursts.

I guess I don't really have anywhere I'm going with this, besides perhaps that being a cyborg will render you immune to some riot control tactics.


2 comments:

  1. You could conceivably hack olfaction by exploiting its link with the limbic system. Actual odors are mostly learned stimuli, however -- associations of a particular smell with fear, for instance, can't be relied on to work for everyone. Which is why I wonder if there's a way to hack it more generally, such that you could induce submissiveness, fear, friendliness, etc.

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  2. interesting... yes,

    If humans could be found to have functionality equivalent to the vomeronasal organ in other mammals, maybe you /could/ manipulate people with the smell of "trust" or "fear".

    As far as I know, the verdict is still out as to weather this functionality exist in humans. Our vomeronasal organ is allegedly dysfunctional, but there is some speculation that the main olfactory bulb may have assumed some of the functionality.

    Perfume companies want you to believe that human pheromones exist and they they can make them. As far as I know, no one has ever actually synthesized a human pheromone.

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