handful of dustNew ways to monitor – and control – neurons are about to become practical. A paper in Neuron by Seo et al describes how researchers at Berkeley created “ultrasonic neural dust” that allowed activity in muscles and nerves to be monitored without traditional electrodes. The technique has not been applied to the brain and has been used only for monitoring, not for control, but the potential is clear, and this short piece in Aeon reviewing the development of comparable techniques concludes that it is time to take these emergent technologies seriously. The diagnostic and therapeutic potential of being able to directly monitor and intervene in the activity of nerves and systems all over the body is really quite mind-boggling; in principle it could replace and enhance all sorts of drug treatments and other interventions in immensely beneficial ways.

From a research point of view the possibility of getting single-neuron level data on an ongoing basis could leap right over the limitations of current scanning technology and tell us, really for the first time, exactly what is going on in the brain. It’s very likely that unexpected and informative discoveries would follow. Some caution is of course in order; for one thing I imagine placement techniques are going to raise big challenges. Throwing a handful of dust into a muscle to pick up its activity is one thing; placing a single mote in a particular neuron is another. If we succeed with that, I wonder whether we will actually be able to cope with the vast new sets of data that could be generated.

Still the way ahead seems clear enough to justify a bit of speculation about mind control.  The ethics are clearly problematic, but let’s start with a broad look at the practicalities. Could we control someone with neural dust?

The crudest techniques are going to be the easiest to pull off. Incapacitating or paralysing someone looks pretty achievable; it could be a technique for confining prisoners (step beyond this line and your leg muscles seize up) or perhaps as a secret fall-back disabling mechanism inserted into suspects and released prisoners.  If they turn up in a theatening role later, you can just switch them off. Killing someone by stopping their heart looks achievable, and the threat of doing so could in theory be used to control hostages or perhaps create ‘human drones’ (I apologise for the repellent nature of some of these ideas; forewarned is forearmed).

Although reading off thoughts is probably too ambitious for the foreseeable future, we might be able to monitor the brain’s states or arousal and perhaps even identify the recognition of key objects or people. I cannot see any obvious reason why remote monitoring of neural dust implants couldn’t pick up a kind of video feed from the optic nerve. People might want that done to themselves as a superior substitute for Google Glass and the like; indeed neural dust seems to offer new scope for the kind of direct brain control of technology that many people seem keen to have. Myself I think the output systems already built into human beings – hands, voice – are hard to beat.

Taking direct and outright control of someone’s muscles and making a kind of puppet of them seems likely to be difficult; making a muscle twitch is a long way from the kind of fluid and co-ordinated control required for effective movement. Devising the torrent of neural signals required looks like a task which is computationally feasible in principle but highly demanding; you would surely look to deep learning techniques, which in a sense were created for exactly this kind of task since they began with the imitation of neural networks.  A basic approach that might be achievable relatively early would be to record stereotyped muscular routines and then play them back like extended reflexes, though that wouldn’t work well for many basic tasks like walking that require a lot of feedback.

Could we venture further and control someone’s own attitudes and thoughts? Again the unambitious and destructive techniques are the easiest; making someone deranged or deluded is probably the most straighforward mental change to bring about. Giving them bad dreams seems likely to be a feasible option.  Perhaps we could simulate drunkenness – or turn it off – I suspect that would need massive but non-specific intervention, so it might be relatively achievable. Simulation of the effects of other drugs might be viable on similar terms, whether to impair performance, enhance it, or purely for pleasure. We might perhaps be able to stimulate paranoia, exhilaration, religiosity or depression, albeit without fully predictable results.

Indirect manipulation is the next easiest option for mind control; we might arrange, for example, to have a flood of good feelings or fear and aversion every time particular political candidates are seen, for example; it wouldn’t force the subject to vote a particular way but it might be heavily influential. I’m not sure it’s a watertight technique as the human mind seems easily able to hold contradictory attitudes and sentiments and widespread empirical evidence suggest many people must be able to go on voting for someone who appears repellent.

Could we, finally, take over the person themselves, feeding in whatever thoughts we chose? I rather doubt that this is ever going to be possible. True, our mental selves must ultimately arise from the firing of neurons, and ex hypothesi we can control all those neurons; but the chances are there is no universal encoding of thoughts; we may not even think the same thought with the same neurons a second time around. The fallback of recording and playing back the activity of a broad swathe of brain tissue might work up to a point if you could be sure that you had included the relevant bits of neural activity, but the results, even if successful, would be more like some kind of  malign mental episode than a smooth take over of the personality. Easier, I suspect, to erase a person than control one in this strong sense. As Hamlet pointed out, knowing where the holes on a flute are doesn’t make you able to play a tune. I can hardly put it better than Shakespeare…

Why, look you now, how unworthy a thing you make of
me! You would play upon me; you would seem to know
my stops; you would pluck out the heart of my
mystery; you would sound me from my lowest note to
the top of my compass: and there is much music,
excellent voice, in this little organ; yet cannot
you make it speak. ‘Sblood, do you think I am
easier to be played on than a pipe? Call me what
instrument you will, though you can fret me, yet you
cannot play upon me.


  1. 1. SelfAwarePatterns says:

    I’m excited by the neuroscience possibilities. Neural dust may be the technology that finally allows us to get a high resolution understanding of the mind’s architecture. That will likely open up all kinds of possibilities. And the ability to influence neural processing may well be a major boon for people with nervous system diseases or damage.

    The possibility of mind control is worrisome, but I think that kind of thing is always the price we have to pay for new knowledge, and the type of fine grained control you see in science fiction, which is what most people fear, is probably a long ways off. And by the time it becomes a reality, there may be protective technologies that mitigate the danger.

  2. 2. Michael Murden says:

    Perhaps the Human Phenomenology project from the previous post may become feasible sooner than we think.

  3. 3. Sci says:

    “True, our mental selves must ultimately arise from the firing of neurons”

    Do you mean this in a necessary or sufficient sense?

    It may still come to pass that something like McFadden’s endogenous field idea will prove correct.

    Hopefully mental dust gets us closer to the answer.

  4. 4. Peter says:

    I meant it in a vague sense and I’m not really sure the firing of neurons is even necessary, just that that is surely the way it works in human beings.

    Yes, fields of some kind are still contenders though Imdo not have any money on them myself. 😉

  5. 5. Hunt says:

    Interesting how they turned to ultrasound after encountering deficiencies with electromagnetics. The radically slower speed of sound vs. light means sound actually give much greater resolution. Ultrasound can be in the gigahertz range! I did not know that. Seems ultrasound is one of those technologies with untapped potential. Perhaps been overlooked due to its more glitzy EM cousin.

  6. 6. Sergio Graziosi says:

    I do not mean to stifle the exploration of possible Sci-Fi scenarios, not at all actually, as that’s where philosophy is at its best (exploring with the mind the range of possibilities that we can’t currently explore empirically).
    Having given a quick look at the cited work (I think I read about the previous instalments in 2014, but I might be mismatching memories!), I can offer a technical comment on theoretical limitations (before we get too excited!). [Note: much, much more could be said, I’ll just tackle a few obvious macroscopic limitations, without discussing any detail at all!]

    I see two main limiting factors:
    1. Size.
    2. Number of “neurodust” particles.

    On Size, Seo et al. do offer their considerations, which I’m taking at face value (life is short, I’m not going to check their maths, sorry!). They included these in the supplementary material (last part), and conclude that (even in theory) “neural dust motes smaller than 90 ?m cannot receive enough power to distinguish neural activity from noise”. To have an idea of what this means, consider that the diameter of dendrites can easily be less than 1 ?m, and that in brains, they get heavily packed.
    Thus, this sort of stuff is still really exciting, but best suited to measure activity along well ordered myelinated nerve fibres (I think!). You’ll find some of these within brains, but you still wouldn’t be able to experimentally pre-determine exactly what it is that you’re measuring.
    In other words, having one mote coupled to the famous Jennifer Aniston neuron, so that it will be able to flag up whether the subject is seeing or thinking about her, is not quite theoretically impossible but it’s very close to impossible. Bar a gazillion of other necessary developments, this technology just won’t allow for this sort of thing.

    One possible workaround is to use many of them, like the “dust” buzzword suggests. People are exploring many ways of concurrently record signals harvested from in-vivo brains (doing great progress), it’s kind of a hard requirement to understand what neurons actually do in real brains, as their networking is (rightly) assumed to be very relevant. Thus, people would adopt this technology in the thousands, if they could hand-pick say, 20 closely related neurons and get the possibility to record from all of them simultaneously (even for long periods of time!), while your subject is alive and well, able to do its thing more or less normally.

    However, by quickly scanning the paper I couldn’t find a head-on discussion on the problems involved with multiple motes placed relatively close to one another (only hints). My impressions: size will mandate the resonance frequency of the piezo component, so, in theory you can use place and ultrasound frequency to differentiate between different motes. Still, crosstalk/interference between motes with similar frequencies will be a problem, and you would also be limited by size: because of resonance, if your smaller mote is 90 ?m, your biggest one (in the same ultrasound “catchment” area, which depends on how well you can “focus” your ultrasounds) can only be less than 180 ?m: one of exactly 180 ?m will receive energy from the ultrasounds expected to turn on the 90 ?m one. You can do all sorts of engineering tricks to work around these limitations, but they will only bring you that far.

    Overall, considering how densely packed are neural projections within brains, the very idea of detecting thoughts via similar technologies is clearly impossible. The scale just isn’t right.

    Doesn’t make the technology less exciting for neuroscientists, nor does forbid exploring “what ifs” inspired by it in here, mind you!

  7. 7. Sci says:

    “I meant it in a vague sense and I’m not really sure the firing of neurons is even necessary, just that that is surely the way it works in human beings.”

    Well it definitely has some relevance to human consciousness. I have yet to see any actual evidence that would suggest non-biological consciousness.

    “Yes, fields of some kind are still contenders though I do not have any money on them myself.”

    Ah I just used fields as an example. Consciousness might also have something to do with other aspects of biology. My hope is something will come up that gets us past the obvious falseness of conscious computer programs and help science get back on track.

  8. 8. Michael Murden says:

    “True, our mental selves must ultimately arise from the firing of neurons”

    Even if we have doubts about ‘sufficient’ I don’t see how we can have doubts about ‘necessary.’ The technical term used to describe a person whose brain neurons are no longer firing is ‘dead.’ We still don’t know if it’s possible for conscious beings to exist without neurons, but to the best of my knowledge no such beings currently exist. On the other hand, I’m not convinced we know enough about what consciousness is to definitively rule out computer programs, or at any rate not enough to definitively rule out machine consciousness.

  9. 9. john davey says:


    “On the other hand, I’m not convinced we know enough about what consciousness is to definitively rule out computer programs,”

    We might not know much about consciousness but there is, by definition, nothing we don’t know about computer programs. What we know is easily sufficient to rule them out as a cause of consciousness (or a cause of anything, come to that)


  10. 10. Sci says:

    “We still don’t know if it’s possible for conscious beings to exist without neurons, but to the best of my knowledge no such beings currently exist.”

    I’d put more stock in cellular life having some consciousness than I would a computer program. As John Davey points out there’s no mystery to the latter unless we’re going ponder both car engine consciousness & whether the turtles you have to fight in Mario Bros died in agony.

    I’d wait for some hard evidence before running into that wilderness of speculation?

    RE: Machine consciousness – sure, just make a reasonable replica of the physical brain’s relevant features. Sadly we remain ignorant of the sufficient relevant features at this point and time, though necessary may include some Turing Machine like components.

    And of course it may turn out organic components are part of the necessary.

Leave a Reply