
Why We Hear Voices in Random Noise - dnetesn
http://nautil.us/blog/why-we-hear-voices-in-random-noise
======
maho
A few years ago, I was struggling to find the weak, electronic signal of an
ion in a single-particle ion trap. I was certain the ion was still in the
trap, but I probably had the trapping voltage wrong and the ion was not in
resonance with the narrow-band (300 Hz) detector. I was trying to think where
to borrow a broad-band FFT detector this late at night to look for the ion,
when I realized I could just mix down the signal to the auditory range and use
headphones to let my ears do the "FFT". I would easily get a few kHz of
bandwidth this way!

But after only a few minutes of listening to the white noise of the (likely
empty) trap, I started to hear voices, among which was the voice of the
deceased PostDoc who had designed the experiment. I took the headphones off
and never used that method again.

I'm afraid it would be quite easy to drive oneself mad this way.

~~~
rawnlq
You might like the book Snow Crash. Spoilers: One of the plot points is that
looking at certain visual pattern (in the form of tv static/snow) can
permanently destroy someone's mind. The later parts of the book explore
auditory signals.

This premise is somewhat believable since there are already people affected by
epilepsy and can't tolerate flashing lights. And even regular folks are
susceptible to optical illusions with (short-term)lasting effects such as
[https://en.wikipedia.org/wiki/McCollough_effect](https://en.wikipedia.org/wiki/McCollough_effect),
[https://gfycat.com/CoordinatedSleepyAnole](https://gfycat.com/CoordinatedSleepyAnole),
etc.

I wonder if they are really some combination of sensory input that can like
you say "drive oneself mad" after exposure.

Side note: Optical illusions also affect artificial neural networks where they
misclassify noise with high confidence as real objects:
[http://karpathy.github.io/2015/03/30/breaking-
convnets/](http://karpathy.github.io/2015/03/30/breaking-convnets/)

~~~
DanBC
I love Snow Crash. And whenever someone recommends it for that bit I want to
also recommend the short story "Blit" by David Langford, from 1988:
[http://www.infinityplus.co.uk/stories/blit.htm](http://www.infinityplus.co.uk/stories/blit.htm)

~~~
mirimir
That. Is. Bloody. Frightening.

------
lb1lf
Also, there's a strong element (methinks) of us hearing what we expect or want
to hear. Extra easy to listen for a pattern if you know it in advance.

(Compulsory anecdote - when studying, I was member of a ham radio club which
dabbled with just about anything tangentially related to electronics. And,
being students, we did so while consuming lots of beer)

Anyway - we did get a thrill from scoring firsts - say, being the first
Norwegian hams to successfully log contact with another country on a given
frequency band / mode.

One evening one of our members was positive he heard an Australian beacon
transmitting in the 160M (just above broadcast AM) band - a band suffering
from epic amounts of atmospheric and man-made noise.

Still, he was adamant he could repeatedly copy the beacon's morse code
callsign - buried in the noise, sure - BUT IT WAS THERE!!!

Luckily, a couple of other members looked into it before he filed the claim;
that particular beacon had been offline for the better part of a year at the
time he heard it...)

------
Al-Khwarizmi
I had never seen this described before, but I have always experimented it with
noise such as from air conditioners or plane flights. Especially plane
flights, as the noise is so loud. However, I don't hear voices, but music
(maybe because I'm a music lover?) And I have learned to control it, so that I
can somewhat listen to the music I want (kind of: I can control the melody,
but timbre control is very limited, and sometimes I lose melody control too).
It keeps me entertained for a while on flights.

A pity the article doesn't really explain the reason. I have always assumed
(just as a wild, uninformed guess) that it's because the noise contains a wide
selection of frequencies, so if our brain is looking for one for some reason,
it can tune the others away and isolate it.

~~~
Nition
I think I know what you mean. It's quite easy for me as well to take a white
noise type of sound and "hear" a certain note that I might decide to imagine.
Then change it a little and "hear" that new note in the same sound.

Like you, I've always assumed it's just because the noise really contains a
whole lot of different frequencies. Interesting to talk about it because I've
never really thought much about it before.

It's a conscious thing for me. I don't really hear the notes in the noise
unless I think them on purpose.

------
Quequau
I suffer from tinnitus predicated on hearing loss and I routinely experience
auditory pareidolia as part of what amounts to prior stimulus replay.

For example where I live there is a test of the civil emergency sirens every
Saturday at noon and every Saturday afternoon I perceive faint echos of the
test well in to the evening.

A more disturbing example is from watching sporting events on TV. I'm a big
fan of rugby so I watch a lot of matches. Late in the evening long after the
TV has been turned off I perceive faint crowd noise and speech which seems
very much to be the announcers (i.e. in their accent) coming from the room
where the TV is located. It's enough to drive me out of my comfort to go check
on things to make extra-double sure that everything has been turned off (even
though I know full well it's off).

It's hard to put into words how distressing these experiences can be. The
"fact" that "only crazy people hear voices" being a significant contributor.
It's also interesting that just knowing that enough people have had similar
experiences that there is a phrase "auditory pareidolia" has turned out to be
so comforting.

~~~
spangry
Sounds similar to 'Musical ear syndrome':
[https://en.wikipedia.org/wiki/Musical_ear_syndrome](https://en.wikipedia.org/wiki/Musical_ear_syndrome)

Unfortunately most of the proposed causes seem pretty speculative to me. Good
old "brain searching for a pattern" seems like the obvious one to reach for.
Fortunately it seems to be relatively common (although it is disconcerting).
I've been experiencing this recently and I swear I can hear AM band radio.

Interestingly, the 'white noise' backdrop for these 'phantom sounds' is
generated by one of 2 machines in my house: an air purifier and an aircon
unit. Even more interesting is that both have air-ionisers built in to them
for air purification purposes (negative ions from the purifier, unclear what's
in the A/C).

At the risk of sounding a little crazy, I wonder if there's possibly a
connection...

EDIT: If there was something to this, it would certainly give more meaning to
the phrase 'babbling brook' (i.e. breaking water negatively ionises the
surrounding area). I know that sounds up there with other hippy-science like
'crystal healing', but take a look at [1] & [2].

[1] [http://www.webmd.com/balance/features/negative-ions-
create-p...](http://www.webmd.com/balance/features/negative-ions-create-
positive-vibes#1) [2]
[https://en.wikipedia.org/wiki/Negative_air_ionization_therap...](https://en.wikipedia.org/wiki/Negative_air_ionization_therapy#Mechanism)

------
zaque1213
A few years ago I was in my room late at night. Everyone else was asleep in
the house. The AC unit in that part of the house was really loud. At one
point, the noise began to sound like ambient chords resonating in a cathedral.
It continued for almost 30 minutes. To this day, I can't explain it. My only
guess is that my mind was taking the white noise of the AC and mixing it up
somehow, allowing me to hear music. I wish I had a more scientific
explanation.

------
ahartman00
"the perception of patterns in randomness where none exist"

"Notably it was an election year, and associations between Islam and terrorism
were widespread, suggesting that such interpretations were not entirely
random"

"The “reality” our minds impose on random noise, influenced by our
idiosyncratic beliefs and predispositions, can also be harmful"

" all experiences of auditory pareidolia are a form of hallucination"

Ive had a hypothesis for a while that prejudice/isms work the same way. The
brain is just trying to make sense of vast amounts of noise. So many sounds,
coming from so many directions, so many colors forming so many different
shapes, which could be other living things, which could have various
agendas(helpful or otherwise), so many memories...

Our egos can't handle the idea that we dont know, so we assume. Its a defense
mechanism I think. After all, history repeats itself, so the most likely
outcome is the one we have seen. Of course, we havent seen very much at all,
and we might have misinterpreted what we did see.

And this leads to thinking we know all about people. We know all about people
we've never met, we know what people are thinking when they do something...
All because we are trying to make sense of the world using a microscopic
amount of information.

Basically I think prejudice, projection, psychological biases, etc are all
'hallucinations' when we try to make sense of a world we cannot possibly
completely understand.

edit can -> can't

------
DonaldFisk
Some people have tried to use this to communicate with the dead:
[http://www.bbc.co.uk/news/magazine-21922834](http://www.bbc.co.uk/news/magazine-21922834)

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

------
UhUhUhUh
Because meaning is our survival advantage.

~~~
PepeGomez
How does hallucinating provide survival advantage?

~~~
taneq
“Fifty thousand years ago there were these three guys spread out across the
plain and they each heard something rustling in the grass. The first one
thought it was a tiger, and he ran like hell, and it was a tiger but the guy
got away. The second one thought the rustling was a tiger and he ran like
hell, but it was only the wind and his friends all laughed at him for being
such a chickenshit. But the third guy thought it was only the wind, so he
shrugged it off and the tiger had him for dinner. And the same thing happened
a million times across ten thousand generations - and after a while everyone
was seeing tigers in the grass even when there were`t any tigers, because even
chickenshits have more kids than corpses do. And from those humble beginnings
we learn to see faces in the clouds and portents in the stars, to see agency
in randomness, because natural selection favours the paranoid. Even here in
the 21st century we can make people more honest just by scribbling a pair of
eyes on the wall with a Sharpie. Even now we are wired to believe that unseen
things are watching us.”

― Peter Watts, Echopraxia

~~~
cardiffspaceman
I think this also explains the survival advantage of apparently hearing your
phone ring while you're in the shower. Those who heed the faint beckoning get
the benefit.

------
hanoz
How common is this? I see faces in the clouds as much as (I've always assumed)
the next man, but I don't believe I've ever experienced hearing voices in the
noise. What's the best sort of 'random noise' to try and experience this?

~~~
bartread
I don't experience it either, although I do sometimes see patterns in the snow
on an untuned CRT TV. Anyway, if you want to experiment there's a white noise
generator at
[https://mynoise.net/NoiseMachines/whiteNoiseGenerator.php](https://mynoise.net/NoiseMachines/whiteNoiseGenerator.php),
along with lots of other generators on the same site.

------
dcow
Unless I didn't read carefully enough, it's not really an answer to why we
hear things. It simply confirms that some people do hear things and reminds us
what such phenomena is called. Interesting nonetheless.

~~~
fallous
Actually it does in that it explains the brain is wired as well as trained to
detect certain patterns, and even in the absence of a true signal it will try
and detect the signals it expects and produce spurious results.

~~~
phs318u
I tried to explain just this to a friend who is a chronic conspiracy theorist.
My suggestion to him was that his brain was detecting signal even where there
was none, and seeing patterns in random events - which everyone is prone to do
from time to time - though in his case the sensitivity is dialled way, way up.

~~~
fallous
Yeah, this is the impetus for things like sympathetic magic and other
misapplications of correlation (or causation).

~~~
fallous
I'm inclined, via intuition rather than data, to think that things like
paranoia, conspiracy thinking, etc are akin to auto-immune responses like
asthma where the absence of real threats causes the system to become hyper-
sensitive and attack itself or things that aren't truly threatening.

------
swayvil
I've heard it's the voices of the dead. I'm going with that.

------
jayajay
Hearing voices in sound (1 temporal + 1 pressure) reminds me of a random
article I read a few days ago about finding patterns in images (2 spatial). I
mention the dimensionality to just reflect that these are perhaps two
instances of the same phenomenon:

[http://community.wolfram.com/groups/-/m/t/995095](http://community.wolfram.com/groups/-/m/t/995095)

Also, here's a more casual/fun post I happened to read earlier today,
coincidentally:

[http://www.dailymail.co.uk/femail/article-3280816/What-
photo...](http://www.dailymail.co.uk/femail/article-3280816/What-photos-s-
faces-suffer-facial-pareidolia.html)

> “I thought I was going crazy. When my air conditioner is on, I wake up and
> hear light conversations. I would go to the window to see if anyone was
> outside, or I would turn the air conditioner off [and] it would stop.
> Sometimes it sounds like a radio.”

I have been sleeping with a fan on for six years, to provide background noise
so that any outdoor audial perturbations would not disturb me as much. When I
have housemates, or I am visiting family, I will often be disturbed so much
sometimes, that I will get up and silent my fan because I am very sure that a
conversation or break-in is happening downstairs. Every time, I realize it was
my imagination, followed by wondering if I am developing schizophrenia or if I
am just a hypochondriac, and then I go back to sleep.

> “I would hear faint voices—whispering, conversing, singing, or chanting! It
> sounded like a crowded room, full of people at a party in a distant room
> somewhere in the building. After a while I came to enjoy the sound, as they
> seemed to be enjoying themselves at the ‘party,’ and it helped lull me to
> sleep at night.”

> If you hear a symphony in Manhattan traffic, thank your auditory pareidolia
> for relieving your stress

Sounds like the better part of a great LSD trip. Good to know I am not alone
in experiencing pareidolia, I thought I was going crazy, too. I can't help but
think the background fan is not perfectly consistent background noise. Jitter
in the wires due to external forces would lead to variable rotation speed in
the motor, which would lead to ups/downs in amplitude and pitch. Our ears are
sensitive enough to capture these distortions, and our brains are powerful
enough to amplify or attenuate our perception of these distortions. Even if
our ears can't capture these perturbations, I would think that the mere
innocent thought or knowledge (or, more ominously, paranoia or suspicion) of
these distortions is enough to create such a perception by the brain.

Initial Reaction: If you form a vector of time-convolution of the output of
the fan with respect to all of your internalized sounds (fragments, phonemes,
words, etc.), over all of their possible phases (accents, volume, pitch,
etc.), you could see which sounds the fan is most likely to resemble based on
how big the corresponding matrix element is compared to the others. Even if
the overlap is .01% with a certain sound, if the next leading overlap is 1,000
times smaller, I bet our brains would pick up on that relative difference. I
know it does with visual field (e.g. optical illusions), and there is reason
to believe that the brain has a grand unified learning algorithm for all
data[0][1] (data is normalized as electromagnetic input anyways)

After reading this, that view is challenged:

[http://www.haskins.yale.edu/featured/sws/swssentences/senten...](http://www.haskins.yale.edu/featured/sws/swssentences/sentences.html#)

Researchers at Haskins lab have gotten rid of the Fourier components in
regular speech, in which case the inner products mentioned above would be
zero, and the synthetic sound _should_ be orthogonal to your internalized
sounds. Nevertheless, I listened to some of this SWS, and could understand it
with 90% accuracy. So, this is very strange. But does it make sense? If you
apply a high frequency shift (e.g. gerbils effect) to some function, you can
still understand the speech, even though it's effectively orthogonal to the
original function. Reading more into the OP paper:

> “spill-over from parts of my auditory system that recognize the air
> conditioner, or the shower or the sound of the kettle, into areas of my
> nervous system that are responsible for processing speech and language.” He
> went on, “And that spillover doesn’t require similarity. It just requires
> some kind of shared activity.”

I am starting to like this theory, and reminds me of an earlier conversation
on HN about corpus callosotomy not getting rid of spillover from other parts
of the brain [2]. But that "spillover" resulted in useful information
transfer, whereas the quote here would suggest it is much more random. Also,
it would suggest that the frequency might not be as important as dA_i(t)/dt,
for all i, where A_i(t) is the amplitude for the ith frequency, like in
Haskins lab.

> But much of our perception of the world also results from the interaction
> between what we might expect to happen in a given situation, given our
> beliefs, and the processing of incoming sensory information

This explains why I imagined the sounds as my family or friends talking or
someone breaking-in.

> minds impose on random noise, influenced by our idiosyncratic beliefs and
> predispositions, can also be harmful

Yes, it is important to take action to ensure you are not going crazy. E.g.
get up, turn off the fan, and listen: did the conversation/robbery stop? If it
did, try it again tomorrow. After several times, one should realize that it is
unlikely that the robberies and conversation are happening, and that it is
more likely due to brain perception mechanics.

[0] [http://newsroom.ucla.edu/releases/ucla-study-shows-brain-
s-a...](http://newsroom.ucla.edu/releases/ucla-study-shows-brain-s-
adaptability-112639)

[1] [https://www.google.com/webhp?sourceid=chrome-
instant&ion=1&e...](https://www.google.com/webhp?sourceid=chrome-
instant&ion=1&espv=2&ie=UTF-8#q=rewire+optical+nerve+mice+rats+audial+vision)

[2]
[https://news.ycombinator.com/item?id=13503186](https://news.ycombinator.com/item?id=13503186)

