Why We Hear Voices in Random Noise(nautil.us)
nautil.us
Why We Hear Voices in Random Noise
http://nautil.us/blog/why-we-hear-voices-in-random-noise
47 comments
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://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/
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://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/
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
That. Is. Bloody. Frightening.
Sounds like noise can cause "hash collision" and pick up whatever there is in the brain map
As a child, I always had an irrational fear of channels on the TV with no signal - you'd get a blast of white noise accompanied with a grainy white noise image feed. Due to the internal amp configurations of the TV, the noise would always be much louder than normal channels, so it was always a shock when you landed on a dodgy channel. Then you would start to see faces and hear voices.
The film Paranormal Activity didn't sit so well with me...
The film Paranormal Activity didn't sit so well with me...
Are you sure that ion wasn't in fact a sophon?
(spoiler alert for Three Body Problem)
In the book, a sophon was a proton that was unfolded from 11 dimensions to 2, had a supercomputer etched on it, and then got refolded back. Its primary job was messing with particle physicists and making them go crazy.
(spoiler alert for Three Body Problem)
In the book, a sophon was a proton that was unfolded from 11 dimensions to 2, had a supercomputer etched on it, and then got refolded back. Its primary job was messing with particle physicists and making them go crazy.
As long as you didn't cross the streams while getting it into the trap, you should be fine.
It is quite crazy. I have experienced this before and once I was on LSD. That was not a nice experience, I heard screaming babies. Easy enough to stop (put on music!) but really creepy. I thought I was going mad for a minute or two.
LSD and cannabis make it really easy to hear things out of ambient or static noises. It's pretty bizarre. But if you're aware of it as it's happening, you can actually control it to an extent and even make yourself hear whatever you want.
Yes, I've also experienced auditory hallucinations with LSD. Also synesthesia. And subsequently, with marijuana as well.
Although the voices are most likely not real, like recognizing objects in clouds, how do you know there really wasn't something there? (Puts pinky next to mouth) ;)
OPs troubleshooting technique was solid; any time you mix high gain with something non-linear with radio transmitters nearby, you can assume weird audio range waveforms on the O-scope are just the local sports-talk AM radio broadcast station showing up in what boils down to an overgrown crystal radio.
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...)
(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...)
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.
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.
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.
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.
I've had very similar experiences sailing. Sleeping in a bunk, you get accustomed to the swooshing sound of the water running against the hull and the drone of an engine. After a few weeks, I was certain I could hear the radio on and knew the tune being played. I asked the crew members who brought the radio and they thought I was crazy. There was no radio. It was uncanny, i thought I heard the song word for word, almost note for note, but it was all in my head.
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.
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.
Sounds similar to '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... [2] https://en.wikipedia.org/wiki/Negative_air_ionization_therap...
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... [2] https://en.wikipedia.org/wiki/Negative_air_ionization_therap...
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.
"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
"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
Some people have tried to use this to communicate with the dead: http://www.bbc.co.uk/news/magazine-21922834
https://en.wikipedia.org/wiki/Electronic_voice_phenomenon
https://en.wikipedia.org/wiki/Electronic_voice_phenomenon
Because meaning is our survival advantage.
How does hallucinating provide survival advantage?
“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
― Peter Watts, Echopraxia
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.
I love that quote, and his work :)
A listener on night shift guard duty from a more ancient or more naturalistic culture would perceive it as spirits trying to send him a message (probably just his subconscious working something out, but whatever it doesn't matter) so he's listening really close to the spirits muttering and then "snap", oh foul words, that was a real sound from a real hungry lion, sound the alarm.
Meanwhile people who hear nothing in the wind get bored, fall asleep, and become snack for hungry lion.
This is ignoring the second order effects of most of the voices are probably your subconscious working something out of your system that needed working out, so you'll be a more well adjusted caveman if your PTSD is worked out because of something you heard the spirits tell you on the wind, than if its all bottled up.
Meanwhile people who hear nothing in the wind get bored, fall asleep, and become snack for hungry lion.
This is ignoring the second order effects of most of the voices are probably your subconscious working something out of your system that needed working out, so you'll be a more well adjusted caveman if your PTSD is worked out because of something you heard the spirits tell you on the wind, than if its all bottled up.
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?
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, along with lots of other generators on the same site.
Many years ago i was during a night shift in an old wooden building, it was windy, and suddenly the noise of the wind going through the cracks turned into some kind of chant, i was alone in the building, in a hill , far from other buildings. It sounded like people chanting old songs. I stood fascinated knowing that was in my mind , enjoying it during several minutes till somehow the sound again turned in to wind noises again.
I can't say what is the best source of noise to experience this, but I have heard what sounded like my brother's voice on aeroplanes several times.
Same - and I'd suggest that the somewhat common usage of white noise as a concentration aid would indicate that hearing voices in white noise is fairly rare.
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.
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.
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.
Religious experiences work the same way. For the sake of politeness we'll assume I'm referring to dead historical religions.
Yeah, this is the impetus for things like sympathetic magic and other misapplications of correlation (or causation).
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.
You might call it "paranoidolia."
#showerthoughts: Isn't everything our senses can use as input technically noise with a probability factor attached to it as far as our brains are concerned, though? As to whether there is 1) intent behind/within the noise, making it a signal, and whether 2) we can identify, parse and interpret the meaning of said signal. Isn't even the most explicit message even in our first language/s (be it auditorial, visual, a smell, touch... taste?) noise until our brain decides it is not?
I'm just not that surprised to hear that the brain is constantly trying to interpret the inputs it gets, what else is there? Is it then that some simply have a lower threshold as to what their brains determine to be signal?
(I really don't know these things, I'm just curious)
I'm just not that surprised to hear that the brain is constantly trying to interpret the inputs it gets, what else is there? Is it then that some simply have a lower threshold as to what their brains determine to be signal?
(I really don't know these things, I'm just curious)
Yes, from a sheer mechanical perspective, but there's a reason the brain is predisposed to detect certain forms of signals within the noise of our sensory inputs. If you're wired to be more inclined to detect things like movements-as-threat then if you're in a high threat environment it is actually beneficial. Unfortunately that same wiring in a low threat environment presents as paranoia and will probably be detrimental to survival.
Now there is a difference between "detect movement," which the brain is wired to do no matter what and the next step of correlating it to "threat!", which could be the result of either biological, environmental, or both.
Now there is a difference between "detect movement," which the brain is wired to do no matter what and the next step of correlating it to "threat!", which could be the result of either biological, environmental, or both.
I've heard it's the voices of the dead. I'm going with that.
[deleted]
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
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...
> “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...
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...
[1] https://www.google.com/webhp?sourceid=chrome-instant&ion=1&e...
[2] https://news.ycombinator.com/item?id=13503186
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...
> “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...
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...
[1] https://www.google.com/webhp?sourceid=chrome-instant&ion=1&e...
[2] https://news.ycombinator.com/item?id=13503186
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.