
Why some people can hear this silent GIF - karlb
http://www.bbc.co.uk/news/science-environment-42237092
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brudgers
I hear it. In my case, I suspect it is a trained response rather than a
mysterious neurological phenomenon. [1] Motion picture sound effects
synchronize distant events such as explosions with the sound of explosions.
When I am looking at a screen simultaneous audible and visual experience is
what I have come to expect based on experience. A delay when watching a screen
would seem unnatural.

One reason I expect it is a unique response to images on screen is that I
don't find anything odd about the thunder coming well after the lightening in
the real world, but a six second delay would be odd in a movie.

[1]: other than the mysterious neurological phenomenon of the human brain
constructing mental experiences from sensory input.

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vamin
I'll propose a theory: very loud, low frequency sounds actually create small
vibrations in your eyes, and most brains have learned to pipe this sensory
input to the auditory cortex. So, the shake in the GIF triggers a "sound"
through your eyes.

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pb060
It could also be the tensor tympani muscle tightening in response to a visual
event that would normally be accompanied by an extremely loud noise.

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Flenser
That's also my theory. I can do it at-will by tensing my jaw muscles and I
hear a "thudding" vibration sound. (Although I wouldn't have known what the
name of the muscle is until your post.)

~~~
pb060
I can't do it at will but few times I was waken up by the "sound" of it
vibrating, quite a scary experience!

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Flenser
I suspect it's due to people tensing their lower jaw in anticipation of a loud
sound. I can do this at-will, and I hear something that I would describe in
similar terms. I also triggered/heard it the first time I watched the
animation (and I don't think I did it deliberately, although I was expecting
it to happen).

My theory is that it's due to the jaw muscles vibrating when they tense, so an
entirely physical sound conducted through the jaw/skull; rather than a
neurological sound. I expect if you stuck a sensitive enough microphone in my
ear, it would be audible.

~~~
koliber
It may not even be tensing of your jaw.

[https://en.wikipedia.org/wiki/Acoustic_reflex](https://en.wikipedia.org/wiki/Acoustic_reflex)

Maybe this GIF is causing this reflex to fire. In the absence of the loud
anticipated sound, your brain may be interpreting the flexing itself as a
sound.

~~~
Flenser
Yes. I expect that's it. I think the jaw tensing may be a side-effect of how I
get that to happen.

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jakeogh
I dont see a gif in this mess of JS. Anyone have a direct link?

~~~
earenndil
[https://i.imgur.com/ga7w2z3.gif](https://i.imgur.com/ga7w2z3.gif)

~~~
jakeogh
(extracted from that!)
[https://i.imgur.com/ga7w2z3.gifv](https://i.imgur.com/ga7w2z3.gifv)

ah. thanks! very cool. I also 'hear' a 'boom/crunch/heavy thing dropped" sound
when it lands, almost for sure due to the camera shake confirming to my brain
the (absurd given the distance and mass!) expectation that the ground moved.
[https://en.wikipedia.org/wiki/Synesthesia](https://en.wikipedia.org/wiki/Synesthesia)

How is it a firefox request for
[https://i.imgur.com/ga7w2z3.gif](https://i.imgur.com/ga7w2z3.gif) ends up
returning html, from which I extracted that gifv link, but a python request
directly for
[https://i.imgur.com/ga7w2z3.gif](https://i.imgur.com/ga7w2z3.gif) ends up
with the correct resource (sha1: f1f24ca2629ed88ee430eba90429fef2a4abc560)?

imgur....

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karlb
I suspect the phenomenon is explained by the Predictive Processing model
(which is explained well here: [http://slatestarcodex.com/2017/09/05/book-
review-surfing-unc...](http://slatestarcodex.com/2017/09/05/book-review-
surfing-uncertainty/))

~~~
sogen
Thanks, Rick Astley's meme also helps to explain things such as hearing
Professor Farnsworth (Futurama) when looking at his memes

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Santosh83
Can't 'hear' anything. I guess human beings are more varied than we seem at
first sight.

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westmeal
I do hear a thud but it's definitely not loud.

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dimpadumpa
Only oddity in BBC's phenomenon is they forced TV license, that they forcing
people to pay who do not tv ?? \- Can anybody explain that ??

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AimHere
Uh, the TV licence covers people who watch live TV broadcasts in the UK
(including watching the internet simulcast of said broadcasts and using the
BBC's iPlayer catchup service).

If your household isn't doing any of that, you don't need a TV license. The
license is basically a tax on watching TV that funds the BBC. What more
explanation do you need?

