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Science

Study Shows How Humans Can Echolocate 136

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.
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Study Shows How Humans Can Echolocate

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  • by TWX ( 665546 ) on Wednesday November 12, 2014 @02:05PM (#48370601)
    ...one ping only...
  • Chocolate (Score:4, Funny)

    by Dimwit ( 36756 ) on Wednesday November 12, 2014 @02:09PM (#48370651)

    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.

    • Funny, I was just going to post that same thing. I keep parsing it as "eat chocolate".

    • I came close - I kept thinking "But eChocolate is a noun, not a verb!"

    • Actually it's toxic to us as well, just a bit less so. If you eat a lot of raw, unprocessed chocolate (which has a higher concentration of toxic theobromine than most processed forms), you're likely to have some problems yourself.

      Theobromine Oral toxicity LD50 (mg/kg)
      Cat ---------- 200
      Dog --------- 300
      Human -- 1,000
      Mouse ----- 837
      Rat ------- 1,265

      • by tlhIngan ( 30335 )

        Actually it's toxic to us as well, just a bit less so. If you eat a lot of raw, unprocessed chocolate (which has a higher concentration of toxic theobromine than most processed forms), you're likely to have some problems yourself.

        Well, we have two things going for us.

        First, we can tolerate a lot more theobromine. Second, we're heavier and thus we can take in a lot more theobromine on an absolute basis.

        Third, our livers process theobromine a lot faster - a dog or cat's problem with chocolate is that they can

        • Huh, hadn't heard about the slower liver processing before, but wikipedia does state a biological half-life for theobromine of 17.5 hours for dogs, versus the 7.1 hours (presumably for humans) in the non-poisoning theobromine article. So they get poisoned by much less and remain poisoned for much longer - not a good combination. Especially combined with the fact that they're, well, dogs. "I eat therefore I am" and all that.

  • Haha, very funny... (Score:5, Interesting)

    by Savage-Rabbit ( 308260 ) on Wednesday November 12, 2014 @02:15PM (#48370725)

    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.

    • Re: (Score:2, Interesting)

      by spire3661 ( 1038968 )
      My only reaction to this article is "Duh". We use echolocation every single day, most people are too 'blind' to actually consciously process it.
      • by Kjella ( 173770 )

        My only reaction to this article is "Duh". We use echolocation every single day, most people are too 'blind' to actually consciously process it.

        No. To use echolocation would imply that you're making the sound yourself trying to find where it reflects back to you and people generally don't do that. Even in pitch dark most will try using their night vision or feel their way around rather than making noises to nobody in particular. Picking out the direction a sound is coming from or noticing obstacles altering the sound is not the same.

        • by sjames ( 1099 )

          Actually, I tend to use ambient sound. You can hear a wall approaching without making a sound yourself.

      • I don't think so. People with normal eyesight probably lack this ability entirely, mainly due to a lack of "hardware" that has to be developed over time. There was some research done that found that the visual cortex can eventually rewire itself to process audio instead. That said, you'd have to be blind at a relatively young age to "learn" this skill, and you'd also need a functioning visual cortex. (Some blind people are blind solely because of a non-functional visual cortex. If they ever picked up this a

        • No actually anyone can supposedly do it,

          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. ... Although some people are more naturally talented than others at echolocation, most got “quite good” after 2 to 3 weeks of training, Wiegrebe says, and could reli

          • That's not what I'm seeing:

            http://www.cbc.ca/news/technol... [www.cbc.ca]

            If what's described in that article is correct, then this isn't happening without a functioning visual cortex.

            • Research suggests that blind people are superior to sighted in echolocation, but systematic psychoacoustic studies on environmental conditions such as distance to objects, signal duration, and reverberation are lacking. Therefore, two experiments were conducted. Noise bursts of 5, 50, or 500 ms were reproduced by a loudspeaker on an artificial manikin in an ordinary room and in an anechoic chamber. The manikin recorded the sounds binaurally in the presence and absence of a reflecting 1.5-mm thick aluminium

    • by Mr D from 63 ( 3395377 ) on Wednesday November 12, 2014 @02:32PM (#48370897)

      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.

      Especially when there is a blackout and you are looking for your chocolate.

      • 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.

        Especially when there is a blackout and you are looking for your chocolate.

        Mmmmmm..... chocolate.....

    • It's not just navigating in pitch darkness, echo location is useful for all manner of things. How many times have you talked to an auto mechanic about a problem and he asks you 'where did you hear the noise...' to narrow down the location of the issue? It is extraordinary to be able to control it and use it more directly.
      • Well, usually not a lot of echos in that scenario, except as confounding factors. So more sonic-location than echo-. On the other hand if you walk into a large room in the dark you probably have a sense of it's size before flipping on the lights due to the change in the reverberation of your footsteps. That would probably be getting at least borderline.

      • 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.

    • by tibit ( 1762298 )

      Most of us actually have this skill and use it, perhaps without realizing it. We go a step further, though: we are passive echolocators. We don't click, but we listen for the multiple echoes of sounds that are emitted by other things, including other people.

      • It's one of the potential reasons that people who stand in an anechoic chamber (I had the opportunity to many years ago now and it was an eerie sensation) can feel very unsteady on their feet.

        • by tibit ( 1762298 )

          I concur. There's one in a science museum I go to often, and it never fails to make me feel wobbly.

    • Maybe, but for some reason, anytime I find myself in complete darkness, I'm also trying to be really quiet. >:)
  • 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.

  • by tekrat ( 242117 ) on Wednesday November 12, 2014 @02:37PM (#48370965) Homepage Journal

    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....

    • 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....

      What are you talking about?

      All Ben Affleck movies are terrible, you're going to have to be more specific.

      Dwardovil? Never heard of it.

    • Real geeks read the comics and piss and moan that the movies suck donkey's balls.

  • Nothing new (Score:5, Interesting)

    by Charliemopps ( 1157495 ) on Wednesday November 12, 2014 @02:37PM (#48370969)

    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.

    • 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

      Are you sure you just haven't been rigorously conditioned to come in and assume she's done something that you need to identify?

      'Cuz, really, I have no idea of WTF you're talking about.

      Then again,

      • I am sure that some people are better or more sensitive to this sort of thing than others. Personally, I've been a musician for decades. So Sound is something I've very keyed in on. I can be laying on the couch and know if one of my totally silent cats enters the room. Something furry like that definitely impacts the sound. It's something I've noticed for a long time. I can actually follow a moving object around the room with my hearing.

        Now, I should clarify, my house is all 1950s hardwood floors. So a furr

    • let's be honest... what's warn you about something new is the credit card sms alert you received! (well, my credit card send me sms alert whenever I pay over 50 €)
  • Could this be an element that led to Khoisan languages? Maybe, for some reason, they were wandering around in dark more than other groups.
  • 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.
    • by Anonymous Coward

      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.

      No, what you're talking about is more like passive sonar. Echolocation is an active form of sonar.

      • Re: (Score:2, Informative)

        Really what Stardner is describing is called "hearing"
        Or even more accurately "hearing with both ears" because the stereo sound field is processed by the brainworks computrons to sense direction of sounds etc
    • 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.

      That's hardly echo location. That's just stereo hearing. The best example I have of that is when I'm skiing - I process where people skiing behind me are by using 2 ears, so that I don't suddenly turn in front of them. No sound generation or echos required....

  • 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

  • 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 ..

  • This topic was covered about a decade ago in the truly excellent Up From Dragons: The Evolution of Human Intelligence [wikipedia.org]. One of the authors is Dorion Sagan, son of Carl Sagan, who wrote the also-excellent Dragons of Eden [wikipedia.org]. A bit outdated, perhaps, but the concepts and ideas stand. I cannot recommend them enough.

  • by Midnight_Falcon ( 2432802 ) on Wednesday November 12, 2014 @05:14PM (#48372771)
    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!

  • 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 largel

  • by godel_56 ( 1287256 ) on Wednesday November 12, 2014 @06:32PM (#48373555)

    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?

    • by dave420 ( 699308 )
      Users don't necessarily want the same clicks, as you yourself pondered. It's far easier for them to figure out which clicks work best for them, and then what variations of those work best in different situations. Just like glasses are different for everyone (who needs them), the clicks would be different too. From what I've seen, yes, different clicks are more useful in different circumstances, more so than just "indoor clicks" and "outdoor clicks".
  • 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

  • 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

He keeps differentiating, flying off on a tangent.

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