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Study Shows How Humans Can Echolocate
sciencehabit writes: Blind from infancy, Daniel Kish learned as a young boy to judge his height while climbing trees by making rapid clicking noises and listening for their echoes off the ground. No one taught him the technique, which is now recognized as a human form of echolocation. Like Kish, a handful of blind echolocators worldwide have taught themselves to use clicks and echoes to navigate their surroundings with impressive ease — Kish can even ride his bike down the street. A study of sighted people newly trained to echolocate now suggests that the secret to Kish's skill isn't just supersensitive ears. Instead, the entire body, neck, and head are key to 'seeing' with sound — an insight that could assist blind people learning the skill.
...one ping only...
Do not look into laser with remaining eye.
You don't want to be mistaken for a Hook Horror or something.
This guy was on the TV show Sightings 15-20 years ago
See Hulu.
I can't be the only person that read the headline and thought it was about some sort of electronic candy.
I read that as "eat chocolate" even after readreading it twice. I still would've been interested, though, since it's toxic to some mammals.
...but it's being eaten...by some...Linux or something...
ears sense the pressure difference when close to an object, that's all it is. clicks would be something else.
You guys can cack as many jokes as you want but being able to navigate in pitch darkness using echolocation is a pretty awesome skill to have.
Only to idiots, are orders laws.
-- Henning von Tresckow
I always turn Chocolocation off in the Settings menu.
for basic use. I have done it myself when in the dark. Slowly, and carefully of course, but usable. I have no doubt that training can turn it into an impressive tool.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
and no one has mentioned Daredevil?
Either turn in your geek cred cards, or admit that the Ben Affleck movie was so terrible that you've erased any mention of Daredevil from your minds....
If telephones are outlawed, then only outlaws will have telephones.
Anyone can do this. You're probably even aware of it if you're married.
You arrive home after work, walk in through the garage and immediately know somethings different but you don't know what it is. You round the corner and your wife has bought a new rug... or cabinet... or something. Do you have ESP? No... the room "sounds" different. How do you know when someones creeping up behind you? Same thing...
I used to deer hunt with my father, and his tree stand was insanely high at over 70ft (he liked to think of himself as a sniper) and you could definitely hear the difference when you were the high in the trees than if you were in my stand which was at a much less terrifying 20ft off the ground.
Could this be an element that led to Khoisan languages? Maybe, for some reason, they were wandering around in dark more than other groups.
You mean everyone hasn't learned how to do that to some extent? Does everyone walk into hotel room walls instead of having some idea of when they're close to an object?
When we walk through traffic and hear cars coming up on us, or know people's position in a room from the direction and magnitude of their voice. It's no surprise that someone lacking an important sense like sight will have much better developed echolocation ability.
I can active echolocate, but I can also do it passively. Does requires more than total silence to do it, but the sounds levels requires are amazingly faint. When it is very quite, it requires more head motion and is slower (1/2 - 1/4 foot/sec).
eChocolate
...for people who have heads, necks or bodies.
I love listening to crazy people who actually talk like that.
I've noticed a similar effect, though I haven't really thought much about *what* qualitative change I'm hearing. Makes sense though - water changes density with temperature, so it's acoustic properties should also change.
--- Most topics have many sides worth arguing, allow me to take one opposite you.
I knew a blind guy who used to walk home from the pub without a stick by tapping the keys in his pocket and listening for the echo, the different envirnoments to the side making different sound as he would walk past.
TFA says (assumes?) that these people's brains measure the tiny difference in how long it takes for the echo to come back. Perhaps, but for every doubling of distance, the strength (spl) of the echo drops by about 90%. That seems like a much, much easier thing for humans to detect. I know the change in reflected volume is obvious when I'm driving next to a concrete wall versus an open lane.
-- Technical details --
Yes, my subject line says "loud", then I gave a measurement in sound pressure level (SPL). I know they aren't exactly the same thing, but the subject line has limited characters and I wanted to get the idea across in a way that is easily understood.
How do I figure the 90% reduction? It's supposed to be 6db, or about 75% reduction right? For a point sound source in free air, yes. This can be analyzed as two sources in free air - source to target, then target to source. The SPL hitting the wall is reduced by 75%, which directly reduces the amount of echo at the wall by 75%. That echo then travels twice as far going back, for another 75% reduction. Additionally, there is the frequency-dependent damping effect, which also varies by humidity. "High frequency" clicks will have significant damping as well, which is also relative to distance.
All I saw was chocolate!
Not only you're not alone, this is a rather common physics experiment (or should be), but it doesn't have much to do with density - it doesn't change fast enough with temperature. But there is something about water that changes rapidly as you go from cold to hot water: viscosity.
Water's viscosity decreases rather dramatically with temperature - about 25% per 10deg C or so. The Reynolds number, a key descriptor of the fluid flow in a given situation, is inversely proportional to viscosity, with factor 1. Thus, in the flow of water in the tap, as you go from "cold" (around 10C) to "hot" (around 60C), the Reynolds number increases by a factor of ~3.5. In the turbulent flow, such a change is easy to hear.
A successful API design takes a mixture of software design and pedagogy.
I've already used it to navigate in the dark and avoid obstacles. Also to detect cars passing by with my eyes closed when bored and waiting for my ride to arrive.
Instead, the entire body, neck, and head are key to 'seeing' with sound
The way this is written up, it makes it sound like the body/head are part of the sensors.
When you read the article, you find the significance is that in one scenario, the blindfolded participants "couldnâ(TM)t move their heads or torsos" and were unable to navigate a virtual corridor. So it's not that the body/head are part of the listening, it's that the person wasn't able to move their ears to listen from different locations. By the same logic, your body/head are key to "seeing" with your eyes ... which is stretching it.
Parallels can undoubtedly be drawn with SAR. Amazing how this capability is built into the human brain (and other animals).
There is a reason we have two ears -- to be able to distinguish the direction the sound is coming from!
But it is not actively clicking and listening to the echo (though probably it would work much worse for a blind person who is also deaf on one ear!)...
Paul B.
This topic was covered about a decade ago in the truly excellent Up From Dragons: The Evolution of Human Intelligence. One of the authors is Dorion Sagan, son of Carl Sagan, who wrote the also-excellent Dragons of Eden. A bit outdated, perhaps, but the concepts and ideas stand. I cannot recommend them enough.
I live in constant fear of the Coming of the Red Spiders.
Ah, that would make a lot more sense, and thus is my personal world-myth is yet again updated with a more plausible explanation in the face of contradictory evidence. Ain't science wonderful?
--- Most topics have many sides worth arguing, allow me to take one opposite you.
If you'e seen videos of him doing the supposed "riding bike down the street," he only gets a handful of meters, slowly, and it is a very painstaking bike ride. They even edit his video to show the more successful parts. I looked into this after seeing his TED talk -- while echolocation seemed pretty neat, it definitely seems like his foundation is exaggerating its efficacy. It definitely does something, his bike riding is awkward at best but I think it's talked up in an effort to encourage others to learn it as well.
Da-na-na na-na na-na Batmaaan!
For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
The noted perceptual psychologist and founder of ecological psychology already stated this in his The Ecological Approach to Visual Perception. He states that visual perception doesn't involve just the brain and the eyes, it is dependent upon the head, neck, and the entire body. Although he was referring to visual perception specifically, he regarded all modalities as being dependent upon the body and it's parts in relation to one another and in relation to the environmental layout. His theories have largely gone unnoticed. I consider this to be another confirmation of his ecological psychology. A shame his work will probably continue to go unnoticed (although concepts he proposed, such as affordances, have been slowly creeping into the psychology literature).
I always thought this was the pipe, the faucet head and aerator and sink changing temp. Not the water itself.
You can hear the difference between a mug of hot water and a mug of cold water if you tap the outside of the mug with a spoon as well. That doesn't have any turbulent flow to it...
Since the operation is performed with fixed ears and the angle of the ears must be changed to catch the various reflections...
Seems to me that there are two obvious technological solutions.
First, one could create a 360 degree sensor on the horizontal plane (Collinear with the ground), that listened for returns, and shifts/recasts them in frequency based on the return angle, then sends the mixed tones on to the ear. So tone is angle(s), and delay is radius. One obvious initial benefit is that echoes can be sensed from any angle, including the reverse, without waving one's ears/head around. Second, by adding frequency to delay, a 2nd easily perceptible dimension replaces that motion of the head. Another is that a single click emission can serve to "Illuminate" surroundings at many angles in the plane, because all return angles are covered simultaneously by the sensor.
Second, the device could be the emitter of the pings, could do so supersonically, and then translate down on echo. This would serve four purposes:
First, to move the clicking out of the normal audio range, so as to not distract others.
Second, to free up the mouth for speech
Third, to gain resolution -- higher frequencies consist of shorter wavelengths, and so they bounce more fully off smaller objects.
Fourth, it provides the same potential you get with sonar and radar: the ability to narrow the ping emissions to a zone of particular interest, with the added bonus of upping the radial resolution as the same tonal range could then be utilized to resolve detail across the smaller zone.
I'm pretty sure there are more implications lurking, but I haven't had my coffee yet. :)
I've fallen off your lawn, and I can't get up.
I do something like this when I'm in the bathroom at work.
I can literally turn on a faucet here without touching the temperature of the water and the instant the water starts coming out warm I can hear the sound difference.
It's like the sound gets more "noisy" and less "linear" when it's hot water coming out. I can even tell as it's warming up since the pitch changes as well then holds steady at full-hot.
Anyone else do this? I'm starting to wonder if I'm alone here.
It's more likely a change in the physical dimensions of the pipe with temperature, rather than anything to do with the density of water. The pipe expands and its resonant frequency decreases.
The famous musician Doc Watson was blind since about 3 years old and in interviews he used to talk about hearing echos off all sorts of things - including tall grass and bushes. He also related to playing hide-and-seek as a kid and being able to tell people apart by listening to them breathing.
I wonder if some sort of artificial pulse generator would be an improvement, rather than producing the clicks yourself.
You'd be guaranteed repeatability and might be able to shape the pulses in order to get a better result. Would differently formed clicks work better at different ranges or with different surfaces?
Sure, but with changing viscosity the sound propagation in the liquid changes - especially that the quality of the resonance in the liquid scales with viscosity (viscous damping!). The speed of sound in the liquid changes too, but the change in the 0-60C range is about a factor of magnitude smaller than the change in viscosity.
A successful API design takes a mixture of software design and pedagogy.
the college had some covered sidewalks between buildings, held up by metal 'poles.' I forget how wide the poles are. 6"? 12"? He could here them ringing and could walk down these sidewalks and stay toward the middle.
==
As a result of being small and being bullied a studying martial arts and chi gung, I have a strong sense of people around. Hypervigilance? Eyes in the back of my head. The most annoying aspect is that the average person are fairly oblivious to the presence of other me, and more oblivious to me (I walk like a Ninja), and, when on foot, are often in my way, or blocking an aisle. Getting such people's (and 80% this includes you) often require me to yell at them. An I guess than makes me rude.
I worked at an opera institute in Austria in the 1970s, and met a blind opera singer who could navigate around the buildings this way, making little clicking sounds. I asked her how she did it and she told me she mostly just listened to the sounds made by her shoes on the floor. So I tried it and sure enough I could detect walls and especially hallways, which would suddenly boom with reverb when you walked past them. As a sound engineer, I can pretty much always tell the size of a room the music was recorded in, even when masked somewhat by artificial reverb.
Try rolling down your windows when you drive and listen to the echo of the whitenoise generated by your wheels. I can hear telephone poles as I drive by, parked cars, even foliage (it sounds "soft") and the doppler shift of the curb as the car gets closer and further away, or a turn lane appears.
Pretty cool.
dpa
You mean everyone hasn't learned how to do that to some extent?
I do it a bit.
I get a sensation of presence of something nearby when there IS something close and I am making sounds I know I'm making (mouth clicks, footsteps, etc.) in an otherwise reasonably quiet environment, or when well-locatable sounds with bursty high-frequency components are present in the environment to provide a sonic "light source" of suitable form and predictability.
It's usually enough to keep from bumping into things. (Even soft, sound-absorbing things like plush furniture, are "visible" as a "quiet lump" - especially if there are hard things around to create acoustic contrast.)
It's not usually consciously apparent that sound is involved, rather than some "extra sense", unless there are really loud echos, like one's footsteps while walking in a concrete or tiled tunnel. (Haven't you had a sense of ambiance in such situations?)
The sensations are so well tuned as an input for moving, dodging, grabbing, and the like, that I've been assuming it's an evolved mechanism (that might have needed exercise in youth to develop properly), like vision, rather than something purely learned.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
...and later after you've eaten it you find out it was meant to be cheap laxative but failed quality control.
Surface tension is dependent on temperature, so the water will splash differently when warm.
I heard that interview, he said that the breath went through the vocal cords and he could hear them if people were breathing harder than normal (like his friends playing.) He also talked about climbing (and falling out of) trees.
It took nearly a minute before I realised that this article is not in fact about electronically transmitting aspects of a certain popular confectionery.
echolocate != echocolate
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
The movie Ray claimed that Ray Charles had this ability; using the sounds from his hard soled shoes.
ROFLMAO... I was reading e-chocolate X-D and I thought they figured out how to make you cum chocolate
Fuck! Now it will take me hours to stop laughing... fuckssake mates, use hypens XD
-- 29A the number of the Beast