We Induced Smells with Ultrasound
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Researchers have made a breakthrough in manipulating our sense of smell using ultrasound, inducing specific scents in participants without any actual odorants present. Commenters are abuzz about the potential applications, from novel marketing gimmicks to therapeutic treatments for anosmia. Some speculate that this technology could revolutionize the way we experience virtual reality, while others raise questions about the neural mechanisms behind this phenomenon. As the implications sink in, the discussion is buzzing with excitement about the possibilities of "ultrasound-scent synesthesia."
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<[SA]HatfulOfHollow> i'm going to become rich and famous after i invent a device that allows you to stab people in the face over the internet
[0]: https://en.wikipedia.org/wiki/Smell-O-Vision
i wonder if some kind of inhalable anesthetic would be a good control. ie, if the normal sensory pathways are blocked and the lifu stim of the olfactory bulb still creates the percept, then maybe it would be evidence that it is working as it appears...
Intriguingly some of the really unpleasant smells never get through to me - I could probably work at a sewage works now. Worryingly I have next to no ability to smell burning, though I do now get the smell of natural gas (or the additive used to make it smell).
In addition to this, I sometimes smell scents that do not exist.
It makes sense for unclassified to smell worse than good, and it'd probably be the biggest category by a long stretch.
(Pure speculation.)
porn + vr + smell
The porn industry has historically been very quick to adopt new technologies, it's easy to see how this could benefit that industry, so it's a logical enough conclusion to draw. They'll very likely be the first commercial application of this, once viable.
This is coming from a place of physical discontent, not moral discontent.
Is it still shitposting if it actually smells nice?
I don't think I'm ready for this technology
On the other hand, I see an opportunity even without tech: porn star perfume collabs: Spray some Gukki Bloom and press play on that video to smell what the star was wearing on the day.
But I guess high-end perfume brands don't want to be associated with actors of the flesh.
https://en.wikipedia.org/wiki/Vibration_theory_of_olfaction
Well, if it’s waves, perhaps principles of consonance and dissonance might apply.
Robert Hooke thought so…
“Now as we find that musical strings will be moved by Unisons and Eighths, and other harmonious chords, though not in the same degree; so do I suppose that the particles of matter will be moved principally by such motions as are Unisons, as I may call them, or of equal Velocity with their motions, and by other har∣monious motions in a less degree.
I do further suppose, A subtil matter that incom∣passeth and pervades all other bodies, which is the Menstruum in which they swim which maintains and continues all such bodies in their motion, and which is the medium that conveys all Homogenious or Har∣monical motions from body to body.
Further I suppose, that all such particles of matter as are of a like nature, when not separated by others of a differing nature will remain together, and strengthen the common Vibration of them all against the differing Vibrations of the ambient bodies.
According to this Notion I suppose the whole Universe and all the particles thereof to be in a con∣tinued motion, and every one to take its share of space or room in the same, according to the bulk of its body, or according to the particular power it hath to receive, and continue this or that peculiar motion.
Two or more of these particles joyned immediately together, and coalescing into one become of another nature, and receptive of another degree of motion and Vibration, and make a compounded particle differing in nature from each of the other par∣ticles.
All bulky and sensible bodies whatsoever I suppose to be made up or composed of such particles which have their peculiar and appropriate motions which are kept together by the differing or dissonant Vibrations of the ambient bodies or fluid“
Page 9: https://quod.lib.umich.edu/e/eebo/A44322.0001.001/1:3?rgn=di...
https://www.wired.com/2006/12/a-brief-history-2-2/
The smelloscope, right ?
I found this History of Smell-O-Vision paper too today:
https://pmc.ncbi.nlm.nih.gov/articles/PMC7691926/
Doing this via ultrasound might lower the barrier to treatment.
But actually it sort of makes sense since (from what I understand) is stimulating an external interface (the receptors), so you're mimicing what the effect a smell would have on you rather than the electrical signal created by the response to a stimulus?
So, N=2 and the people in question are co-authors. I'm not in this business, but isn't this too... early to publish?
The issue is that lay people read every paper or post as if it were a final proclamation. They’re not. Even a peer reviewed paper on the cover of Science or Nature is still not “proof” of anything, science doesn’t produce positive confirmation. It produces evidence that taken together suggest one prior is more likely than another.
Bayes Rule is very intuitive. We update the prior by the likelihood of the evidence under a given prior divided by the likelihood of the evidence. That’s all it is.
Unfortunately, there is a very strong motive to flag plant. Academia is a water full of sharks.
is this like some second meaning or smth?
why is there a knife on the headset?
It's objectively cool, but very curious about the safety as well.
https://human.research.wvu.edu/fda-regulated-devices-used-in...
---
9. Does FDA require IRB review and approval of off-label use of a legally marketed device?
No, when a physician uses a legally marketed device outside its labeling to treat a patient and no research is being done, IRB review is not required. Note: Although not required by FDA, an IRB may still decide on its own initiative to review such use. Yes, when the off-label use of a legally marketed device is part of a research study collecting safety and effectiveness data involving human subjects, IRB review and approval is required (21 CFR 812.2(a)). For additional information on the off-label use of devices, see the FDA Information Sheet guidance, “ ‘Off-label’ and Investigational Use of Marketed Drugs, Biologics and Medical Devices.”
......
...OH you probably mean for the purposes of stimulating things OTHER THAN SMELLS
> "We found different scents by steering the beam over ~14 mm (20 degrees at 4 cm radius). The distance between freshness and burning was ~3.5 mm."
> "The olfactory system potentially allows writing up to 400, if not 800 due to two nostrils, dimensions into the brain. That is comparable to the dimensionality of latent spaces of LLMs, which implies you could reasonably encode the meaning of a paragraph into a 400-dimensional vector. If you had a device which allows for this kind of writing, you could learn to associate the input patterns with their corresponding meanings. After that, you could directly smell the latent space."
This just makes me grin with total delight. Completely freaking fascinating.
What are the chances baby ultrasounds are doing this unintentionally?
So, the pressures are high enough to be stimulating them! But most diagnostic imaging happens at 1-20 MHz, while most neurostimulation seems to occur at few-hundred kHz (we were at 300 kHz, on the mid-high end). So I don't think it's likely that babies are being sent smells?
https://en.wikipedia.org/wiki/Olfactory_white
These smells have everything: Harsh solvent-like stuff like strong alcohol or glue, rotten fish amines, off-sweet halocarbons, things like burnt plastics, excrement, or stuff that defies description as to their lingeringly terrible sensation of olfactory wrongness (selenium compounds).
There is actually a thing called "cadaverine", that should tell you enough.
Still, every sufficiently large storage space I rememebet had this identical, not unpleasant, thickly sweet, but not easily defined smell.
So to conclude, I think it's a brain glitch when we input everything, all the smells, at the same time.
Could I shoot you guys a message when I make my way down to Caltech to try this out someday? :)
If you get in contact with the researchers, please let us know how it went.
If they _lost_ their sense of smell, they had something to compare it with.
E.g. smelling something rancid for the first time - how strong of a negative reaction will it be compared to others who grew up with this negative association. Would I ever even be able to map most of the smells others have memorized to their origin? I really hope I get to find out someday.
Don't get me wrong, I would love this finding to be replicable, it would be pivotal as what other nerves could we stimulate to change perception (think pain, mental health issues, loss of senses).
Also, I wonder if this could take us closer to understand a little bit more of how the brain works. Like this could be a great way for normalizing 'inputs' and see how different brains react to it.
Very very exciting news, but I will hold on my hype until someone else can replicate this result.
These are exactly the types of smells people report when they get head CT scans (I've experienced it myself). Always thought it was ozone forming but perhaps it's more interesting than that.
This reminds me a bit of the escherian staircase video from 10+ years that went viral. A bunch of college students walking down the stairs, acting amazed when they found themselves back at the top. It was great acting and video editing, but it was fake and all part of, if I recall correctly, an art project.
I don't want to dismiss it outright either, seems cool as hell. But it's remarkable to me that all it takes is a blogpost to get this amount of uncritical acceptance of a demonstration.
I think this is cool, plausible and warrants investigation, but not suspension of disbelief. There needs to be a better way to go about this than responding "what about Galileo!?" to any principled application of critical thinking.
One has to set prejudice to the side and examine the claim being made to apply criticl thinking.
To be frank the reason that make me question it the most is how repetitive the redaction is. Seems LLM-like.
However, that's not a valid reason to discard an interesting result.
Translation: We’re very concerned that the only projects getting funding right now have to use AI.
[1] https://en.wikipedia.org/wiki/Long-term_nuclear_waste_warnin...
Our fingertips feel using low frequency sound generated by our fingerprints passing over things.
This kind of tech should be developed as open-source projects, even for the firmware and hardware. A sufficiently advanced version of this, if widely deployed as proprietary blackboxes like smartphones are, would allow one consciousness to take over multiple bodies without their original owners knowing.