EEG shows brain can simultaneous encode two speech streams | Hacker News Reader

EEG shows brain can simultaneous encode two speech streams

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Related, but this reminds me of the story by Richard Feynman [1] when he practices counting up to 60 seconds in his head, and after many experiments around what he can do simultaneously conclude that he can simultaneously count and read but not speak. Later sharing this to John Tukey, he's told that Tukey can't read while counting but could speak while counting.

Turns out Tukey is visualizing looking at a tape, while he counts, while Feynman imagined himself talking to himself, so he couldn't speak while counting but Tukey couldn't read while counting

>By that experience Tukey and I discovered that what goes on in different people's heads. when they think they're doing the same thing - something as simple as counting - is different for different people. And we discovered that you can externally and objectively test how the brain works: you don't have to ask a person how he counts and rely on his ownobservations of him-self; instead, you observe what he can and can't do while he counts. The test is absolute. There's no way to beat it; no way to fake it.

>It's natural to explain an idea in terms of what you already have in your head. Concepts are piled on top of each other; this idea is taught in terms of that idea, and that idea is taught in terms of another idea, which comes from count- ing, which can be so different for different people!

>I often think about that, especially when I'm teaching some esoteric technique such as integrat- ing Bessel functions. When I see equations, I see the letters in colors-I don't know why. As I'm talking, I see vague pictures of Bessel func- tions from Jahnke and Emde's book, with light- tan j's, slightly violet-bluish n's, and dark brown x's flying around. And I wonder what the hell it must look like to the students.

[1] https://calteches.library.caltech.edu/3591/1/Feynman.pdf

I can also count while reading, I just tried it. But I can't write while counting.

I can have one interpretation and one generative task running at the same time.

I can count while reading and it's fairly easy

The sentence below will be written when I'm counting to 60

Let me try counting while writing, it's hard with tons of mistakes and typo (like switching count with write), it's also demonstrably slower with this whole sentence taking more that 60 count. Verbalizing the count is way harder and I need frequent stops to gather my thoughts

counting aloud or in mind

the former is harder but still doable

It really does feel like reading and counting can occupy separate lanes, while writing and counting are both trying to use the same internal narrator

A CPU designer might call them execution ports.

Well, FWIW, I can easily write and count. It's actually way easier than I thought and takes no effort. Perhaps due to automatic touch typing while talking and thinking about something else etc? I can actually type and think about something else, never really noticed that before.

Reading and counting is harder for me. I can do it, but it's tiring. Those feel like they share lanes to me.

With touch type it would work if I buffer the work ahead of time and then I can type out the buffer while I count.

Sort of like: I think what I will type then when I start typing I start counting.

I do not generate what I type while I count, but think of it before I do it.

This is a nice example of using interference as a window into representation

Interesting, I experimented a bit with this when my daughter was younger. I used to walk around the room with her in my arms singing to get her to sleep. To ensure she would be settled I would then count 300 steps before putting her in the cot. I discovered I could count and sing at the same time by visualising the number in my head, instead of using my inner monologue. But it requires more focus to maintain.

Thankfully these days she can get herself to sleep. But I miss it sometimes

If you miss it, maybe she does too. You can still do it even though she doesn’t need it

Maybe. But as a parent, sometimes you have to make sacrifices (or force them to make sacrifices) as otherwise they won't have space grow.

Ugh, yeah. It’s the worst. It’s the best.

It reminds a bit of musicians tracking rhythm. You can somehow feel a beat after a bit practice even when not directly paying attention to it and it's not too hard to associate it with an increasing counter (somehow). It sounds hard, but it is quite doable.

> You can somehow feel a beat

If you play in an orchestra, you might have the visual memory of the conductor and their time signature motions helping you along.

The somewhat jarring tick tock of a digital metronome can also be encoded into a sort of background track that plays more or less automatically in your head.

> If you play in an orchestra, you might have the visual memory of the conductor and their time signature motions helping you along.

Or on the other side of the spectrum, most DJs learn to "feel" beat counting and phrases, more or less by feeling. After a while, your head kind of goes "1,2,3,4" by itself, and the phrases of the songs "feels" like they're about to come, then they come.

yeah, doesn't the multitasking in this thread feel a little bit like what i imagine playing the drums is like? i've done some low-key drum-playing sorts of musical things in my life, and it was the disconnection point when you genuinely had 2-3 different things to focus on at once that i found my brain to be lacking. i observed the same with piano, but i had much more of a knack for piano, so it was only the rare song that genuinely required tracking three things at once... and those kinds of songs are hard enough for most mortals that people just pin them all as "dw those songs are super hard", when in reality it always felt like that specific skill was the thing that was lacking, and besides rote memorization i never found some way to lick it all the time. when i was really in flow, though, it would be completely effortless. it's bizarre.

Very true. Strangely, I also found this in competitive games. You get a very accurate sense of cooldowns without consciously tracking them. StarCraft with different build times, Apex Legends with character abilities, etc.

> I discovered I could count and sing at the same time by visualising the number in my head, instead of using my inner monologue. But it requires more focus to maintain.

Funny timing for this comment, just last week I was running slowly on the treadmill and was counting my steps due to curiosity about steps vs time, and decided to count using images. It definitely takes more effort but I think it's because I hadn't tried it before.

I would hold the tens digit image static and repaint the ones digit until it rolled to the next tens digit, which meant very limited effort was required to retain the tens digit image and most effort was transitioning the ones digit.

The ones digit would not just instantly flash in place, it took a small amount of time and some noticeable deliberate effort for the process to complete, and then it was just in maintenance mode until the next transition.

I've noticed something similar. I can listen to audiobooks and follow/absorb what is going on without really paying attention, as long as I am not trying to read something. I can't follow an audiobook and read at the same time. This is probably because I subvocalize when I read. I have taken speed reading courses but I don't enjoy reading that way. I like feeling every word as I read.

I read by imagining a voice saying the words. Is that not how everyone reads?

I have two modes of reading - when I read a story to enjoy, I read it to myself with inner voice saying the words (like internal audiobook). When I read to gather information quickly, I try to just absorb as much keywords as possible by quickly glancing at text and trying to directly absorb the text, rereading where needed.

No, I can do both but absorb much better when I internal monologue it but can read much faster when I don't. Some people don't internal monologue it at all.

If you're in the market for another "wait I thought everyone did it X way?!" surprise look up aphantasia where some percentage of people can't mentally "picture" items and there's a whole spectrum of vividness. I've yet to find someone not surprised by this no matter where they are on the spectrum.

It is not.

Not at all. I can do it, but I have to actively produce it. Don't see much use for it except when reading quality fiction. It's dog slow IME. You are a fast reader?

You might wonder how I read and it's a bit like how you can watch an intersection and know what to do without verbalizing "there is a bike", "there is a car". You just get the situation and understand it. Sentences are like that as well.

Personally it's the same way you look at a thing and get a mental sense of "this is that thing" without having to scan every detail right away, you look at a chunk of a sentence or words and get the sense of its meaning, and you can vocalize that in your head if you want to

I have two reading modes: A narrative reading mode where a voice reads the text, and a speed reading mode where my eyes scan down the page and recognize the characters, words and phrases without any voice.

No, and this is one of the first things that tends to come up in any guides on how to read more quickly: reading without internally vocalizing, in order to not limit reading to the speed of vocalizing.

Some people can switch back and forth between both readily, and use them for different purposes. Some people read only in one or the other mode.

I also want to know , how people read . I read silently without talking. I also heard that some people read by speaking it loudly( which doesnot help a lot for me)

so can we conclude that the people reading loudly visualizing the words , and the people speak silently , internal-vocalizing the words .

I think there are at least two ways of reading - maybe more.

When I'm normally reading it seems I'm basically going through the motions of reading it aloud to myself, but then suppressing the final verbalization. Sometimes I find myself relaxing in front of the computer with the middle finger of my left hand resting on my lower lip/teeth (I know - sounds odd!), and I can feel some micro-movement in my lips as if they want to move according to what I'm reading.

My other form of reading is a poorly trained version of speed reading where I'm rapidly scanning the page trying to at least get the gist of it, which seems to be more of a purely visual process, recognizing word forms but not getting as far as trying to pronounce them internally (which seems to lead to better understanding, perhaps by slowing down/serializing the process to be more similar to hearing speech).

This happens to me sometimes when I'm tired and it ruins my enjoyment of the book. Normally I go straight from page to imagination without much conscious awareness of each word.

> I like feeling every word as I read.

I know what you mean. I don't typically sub-vocalize, but when I run across a particularly beautiful bit of prose I slow down in order to hear it in my head. If I'm on my own I might read it aloud.

i can't talk and listen at the same time to save my life, but as an intern at the Idaho State Historical Society a million years ago i did learn how to transcribe in roughly real time typing and listening. funny how those boundaries work-- feels like a "choose two of these three things" sort of... thing. i also don't find that i have the sort of internal narrative/voice in my head in the way that others do, so i would have to imagine that plays a role on some level. not that basically anyone with sufficient time can't learn to transcribe in near real-time-- it's not at all some sort of profound skill-- i was just struck by how quickly i could pick that up compared to other things.

> while Feynman imagined himself talking to himself

ironic )

This has everything to do with the fact we have two brains. The left and right brain (more specifically the left and right hemispheres of the Cerebral Cortex) hold different functions cognitively, control the motor movements of the opposite sides of the body, and communicate thru the Corpus Callosum. Your full consciousness, or thought, is almost like a 'stream' created at this meeting point of the two brains where the neural traffic is so dense (more like my own theory...). However, if you were to find a patient where this connection is severed, like an epileptic patient whos Corpus Callosum was surgically bisected to cure them of chronic seizures, you would then have someone with 2 separate brains that cant talk to one another. This is split brain theory. I wrote a paper on this in undergraduate and id have to pull up a ton of other details, but essentially go watch videos on Michael Gazzaniga and Dr. Roger Sperry's experiments with these people. They would experience the right brain reaching for one outfit to get dressed in the morning while the left brain "thought" the idea of another outfit, so they would be very confused. Its very revealing to the mapping of our brain and all the different human functions, and how we learn! Then you lead down the rabbit hole of Bicameral Mind... but anyways, i believe thats why everyone can count in their left brain, and then from there its up to each brain system to figure out how to map the second task to the right brain so they can enter the consciousness stream simultaneously. There is an internal mechanism everyone develops themselves and Feynman is showing you can test that. Its probably right around most humans cognitive limit to use the right brain to help either reading OR speaking as the left brain is the primary handler of all of these (math, reading, speech). I also think thats why Feynman saw colors with his math; his right brain was assigning a unique identifier (color) to his logical problem being worked out in his left brain (all the different symbols and letters). Fascinating.

The article's EEG images don't seem to suggest this is due to two brain hemispheres.

The original comment is talking about a related phenomena from Richard Feynman's own thought experiment. The article itself is talking about how the brain pays attention to 2 other people speaking at them; its not the same thing. Article focused on monitoring and listening, the comment is talking about one's own brain trying to complete 2 simultaneous tasks consciously.

Fun fact, the Zizian AI murder cult is similarly obsessed with the idea of two hemispheres being separate brains. They also believe gender dysphoria is a trait present or absent within each hemisphere.

Their long term goal was to abolish sleep by making one hemisphere of their brains sleep at a time, leaving the other to be awake. Supposedly this would allow them to work more and have more sex. In reality, they all simply went insane, committed pointless murders, and ended up in prison.

As it happens, dolphins and whales do this so as to not drown, and they consequently have an underdeveloped hippocampus and take 3x as long as primates to learn the same things.

Long story short: don't mess with your sleep or you might start a murder cult.

> don't mess with your sleep or you might start a murder cult

Or: don't select members that are really into bicameral mind ideas

In my extremely limited experience, some crazies are into split brain thinking, and some crazies have symptoms of split brains

I can't remember the book now, I think one of Antonio Damasio's? He recounted an experiment with a patient that had a severed corpus callosum where they put a wall between the eyes and showed him two different pictures, asking him what he saw, and he wrote one answer and spoke another, without any indication either half of him was aware the other half was inconsistent.

It was terrifying 20 odd years ago to read this kind of thing, but it's amusing in light of all the obsession with productivity hacking in Silicon Valley that I could almost see someone with a YouTube channel doing this on purpose to try and be able to accomplish simultaneous tasks a normal person would be tripped up on by the need for a normal brain to produce a single consistent narrative.

it does feel like quite the coincidence that 2 seems like the magic number and we do, in fact, have two hemispheres. i doubt that the processing for any of these tasks falls strictly down the left vs right hemisphere, but i do kind of feel like our consciousness is kinda built on having a sort of internal tick-tock cycle, and we do certain kinds of thinking on tick and others on tock. but that is just armchair introspective dilettante neuroscience-- not to be confused with the actual thing.

I wonder how musical counts interact with this.

How do we know, or would Feynman know, that they can count while reading and not just that counting and reading are simple enough tasks broken down into discrete steps that our brains can context swap in an unnoticeably short unit of time?

Just trying to read your post while counting at a consistent pace I associate with roughly 1 second per number, it didn't feel like I was reading words but instead scanning them and understanding them after the fact from memory. Usually when i read I hear the words 'in my head' but not while counting at the same time.

Honestly my takeaway from this is that simple experiments like this are very important in identifying how brains work. I am admittedly a fanboy of Feynman, but I believe these kinds of questions are worth a dozen EEGs or fMRIs asserting how the brain works.

Interesting, I often sing a good night lullaby to my kid and have discovered it’s trivial to read while doing so. But I just tried talking while counting in my head and it felt like a brick wall was blocking me.

Singing and playing guitar was super painful for me. Got easier after the first song, so now it's just painful to the people hearing me.

I remember a story about people who stutter not stuttering while singing.

> I remember a story about people who stutter not stuttering while singing.

“Everybody's sayin' that the Scatman stutters

But doesn't ever stutter when he sings

But what you don't know, I'm gonna tell you right now

That the stutter and the scat is the same thing”

https://en.wikipedia.org/wiki/Scatman_John

Try counting by imagining fingers in your head and talking at the same time. (-;

i wish i could do syntax highlighting in my head

I liked your post and I enjoyed reading it, who doesn't enjoy reading about Feynman?

But let's get scientific about this, you say:

> The test is absolute. There's no way to beat it; no way to fake

Where's the proof of that?

I dont know why I cant work or read or focus while listening to music , is this the reason why.(or music takes all my attention)

If reading aloud a children story, you may notice you are able to maintain an independent unrelated train of thought. While doing so, I notice that occasionally extra mistakes can "leak" into the story telling - e.g. you read a single word incorrectly, maybe substituting a word from your other train of thought.

Interlinked.

or any other reading for that matter!

I definitely cannot do that. Crazy.

The ability may take time to develop. If you have a couple under-5 children handy, who'd love the ritual of having the same ultra-simplistic and repetitive books read to them every night, night after night after night, when your head is probably full of grownup stuff that you gotta get done...

I can do that, and i notice that i kinda stop thinking about the reading and put more "brain resources" into the independent train of thought. Then i realize i was reading all the time without putting any effort in it

Yeah it's like I suddenly realise I haven't been thinking about the reading and I'm near the bottom of the next page somehow.

When I was a kid, my dad (a physicist) would often read stories to me and my brother. He would sometimes fall asleep while reading, and we could tell when that was coming because suddenly our children's story would stop making sense and get filled with all these big physics terms.

Oh yeah, I have been sleep deprived so much that the things that I said made no sense. I still formulated sentences but they did not have any meaning. In fact, I noticed this myself and I was like "fuck, what I just said made no sense". This happened a few times. It is a pretty interesting experience.

I had the same experience after almost 4+ days going without sleep. A friend came to check up on me after I fell asleep, I woke up and started telling him a whole story that made no sense, but I said it with such importance that for a week he was asking me to explain to him what I meant...which I don't remember exactly, but it was important.

So, sleep deprivation leads to temporary schizophrenia? Who could have foreseen this?

Sleep scientists and drill instructors!

This sometimes happens to me when I get a migraine.

A sentence can be coherent in the formulaic sense, but complete nonsense as far as words. I immediately notice that it's incorrect, but I don't have the ability to fix it at that moment.

Yes! I immediately noticed that what I said was wrong (even though the word I said still felt somehow connected to the thought I was trying to communicate). I was really worried at first when it happened because at the first time I had no idea sleep deprivation would cause this, or that I would experience it.

I had no idea migraine causes this as well, interesting.

That is an amazing sleep indicator: once the rabbit starts discussing thermodynamics, dad has left the building

Somewhat related, but when I was sleep deprived and falling asleep during a general relativity lecture in college, I caught myself reasoning through the series of equations written by the professor on the board, and agreeing as to their validity with the explanation in my mind being that my parents are in a foreign country. My brain was convinced it had logically checked the progression and that it made sense, but it was based on this irrelevant fact. The experience always makes me wonder what falsehoods we individually or collectively use to convince ourselves of things being true.

The ability of the brain to do that gives me 15 min of quiet time to think about problems each evening. But you cannot follow the story in that mode, and the whole facade will collapse on a single innocent question...

> "Dad, why did he steal the biycle?!?!"

> ".... what?"

In school, our teachers made us take turns reading the textbook. When it was my turn, I focused entirely on how my voice sounded, trying to match my cadence and tone to the punctuation. The moment I finished the paragraph, I would have to quickly re-read it in silence just to understand what it actually said.

I think I still can't read a non-trivial text aloud while trying to make sense of it at the same time. I need the two streams just for one text.

The reading task can stay largely automatic until both streams try to use the same speech-production machinery at once

Well, perhaps sadly, I maintain trains of thought unrelated to my environment all the time. It's because the default state of the world is so incredibly.. bland I really, really cannot take it without something going on.

I learned at a young age the best way for me to be a good out-loud reader was to think about something else while I'm reading aloud. If I concentrate on the words and the reading aloud I screw up but if I think about other things, even HOW I'm doing while reading or thinking about what I'm reading and going to say NEXT, then I can read aloud flawlessly.

I can have an internal monologue about something completely unrelated to the story while reading it out aloud, but I won't be able to follow the story. I don't think I make mistakes, but I probably fail to put the correct intonation on sentences which require higher order thinking to infer the emotions of the characters in the story.

I am reading dozens of books to my children (mostly of Enid Blyton) and I am able to simultaneously think about something else (work stuff, household, HN subjects etc). It lasts a few minutes during which I don't follow what I am reading and I come back and need to start again. Definitely the phonological loop (eyes...mouth) functions independently from the memory-processing-executive cognitive pathway.

As a pilot and a radio officer, I have always been able to process and service 2 audio streams simultaneously. So not surprised with this finding.

Perhaps a dumb question but are they center panned (or mono, i.e. talking over each other) or is it split left ear/right ear when they come through the headset?

Airplane radios are generally broadcasting and receiving mono. There are modern headsets that can also play stereo, but only for onboard music or intercom purposes, if the plane supports it. But in planes with 2 radios you can usually configure their I/O individually. So you can listen (and also talk, although that makes sense less often) on two frequencies at the same time.

Yes of course, the transmitted audio would be mono. I meant one radio in one ear and another radio in the other ear, or if you mix them and they both play in both ears. But it sounds like they're mixed (talking over each other in a single audio stream).

Yes. I have never seen any system (planes or elsewhere) that splits multiple voice communication inputs so you hear different streams in different ears. How would that be different (let alone better) than having both streams in both ears? It's not like your brain can process each ear separately.

But of course your brain can process each ear separately. You have a holistic conscious experience, but that is like a hallucination constructed by your brain for your own benefit. The raw signals are indeed "in stereo"

There are generally 4 ways you can deal with presenting two independent mono sources to one person using headphones:

1. Mix them together into one mono channel and send that to both ears.

2. One in each ear.

3. Make separate mixes for each ear. For each ear's mix make one of the sources louder than the other, picking a different source to make louder for each ear.

4. Like #3, but also add delay in each ear's mix to the source that is weaker in that ear.

#2 is generally better than #1. Personally I'd find it annoying because it is very unnatural, but it makes it a lot easier for the brain to separate the sources, makes it easier to focus on one and ignore the other if you need to do that, and prevents the auditory masking you can get when two sources are in same place in your perceived audio space.

#3 fixes the masking problem with #1 but #2 still because it is still easier to focus when you need to. Also, in each ear the weaker signal is unnatural and the brain expends some effort to filter it out, which is fatiguing over long periods.

#4 is by far the best. It solves the long term fatigue problem from #3 because our auditory system is built to expect a weaker version of anything one ear hears first to arrive shortly later at the other ear, and automatically filters it out instead of having to do it at a higher level. The delay shifts the perceived source of each voice to somewhere outside the head instead of somewhere inside, which is more natural, which is much less fatiguing than the "one voice" per ear approach (the brain almost always does more work when something seems unnatural).

Many military planes use #4, as do some Airbus models.

Different voice inputs in different ears wouldn't help since our brain processes auditory input on left/right side of brain based on the type of input, not which ear it came from. Speech is processed on the left side, and non-speech (music etc) on the right side.

> It's not like your brain can process each ear separately.

If you've ever seen a dance music DJ (Tomorrowland is streaming on Youtube right now!) - that's exactly what many of them do.

To DJ a continuous mix as is the norm for this style - generally you'll have headphones on, but only covering one ear. You'll listen to "currently playing" though your right ear, through the venue sound system (well, it's monitors). You'll also be listening to "up next", on the other record/cd/mp3 deck, through the headphones to your other ear. And you'll work the pitch slider, trim controls etc and hopefully produce a good mix!

Not everyone does it like this, some have the headphones permanently on and mix in stereo both tracks at both ears. Or split ears, headphones only - that is an option on the usual Pioneer mixers. But it's surely the most common mental image of a club DJ to have them holding their hand to their headphones on one ear only, I'm sure!

> I have never seen any system (planes or elsewhere) that splits multiple voice communication inputs so you hear different streams in different ears.

PS Engineering PMA450B is one, but most GA aircraft I’ve flown work like this.

> How would that be different

It would be different based on the fact you’d hear one conversation in your left ear, and another in your right ear.

> (let alone better)

Beauty is in the ear of the beholder.

> It's not like your brain can process each ear separately.

Different brains function differently.

Thanks, this was the info I was originally after :)

They are mono, but I was trying to say that with practice, you can process 2 independent audio streams simultaneously irrespective of whether they are mono or stereo. For example, I am able to keep track of 2 people talking at the same time. I obviously can't respond to both but can maintain independent contexts.

I wonder if piano players find that easier too, compared to lay people.

I think it was wondered whether you were having the independent streams panned hard to the left and right ears and if that had something to do with hemispheres of the brain and the processing efficiency.

That’s a super interesting question. I don’t think I isolate one stream to each ear since I can process them through headphones as well. Also routinely when I am working as a radio officer, I have conversations with live humans in the room while listening and responding to audio over RF through the headphone.

To be honest, I can’t articulate how I do it. I just somehow manage to do it.

I do it too, but I "buffer" one person's speech while I process the other's, and vice versa. Do you process both at once?

I wonder if reading techniques (i.e. human TTS) are also a bit like this. You have to "read ahead" and maintain a mental buffer, in order to parse the sentences so that you can put emphasis in the correct places, timing etc. So the eyes and mind are ahead of the speech.

That tracks. As a teacher I sometimes find myself conversing with multiple kids simultaniously as well. If it's nothing too deep that requires full focus, it works. (Though I do find it tiring and avoid it.)

I've always been impressed by the controllers in centers and TRACONs. They can have multiple frequencies they're monitoring in each ear, and no matter how polite we try to be we (pilots) have no way of knowing if we're stepping on a call on another frequency. They just have to deal with it. Not to mention communication amongst themselves to some extent as they hand people off, though I haven't been in a tower for a very long time, that may be automated/digital now.

And it's not like pilot/controller conversations are about weekend BBQ plans. It's as information dense as possible without sounding like a METAR report.

The drive through window staffers at restaurants do this, and it’s crazy. They will tell me my order and total, accept payment, and send me to the next window, all while listening to the next person tell them their order.

Many mindfulness practices seem to direct attention at two place at once, to quiet the inner voice. Perhaps this relates to more than just speech, but to attention itself. George Gurdjieff's "The Fourth Way" deals with self remembering, and his pupil, P. D. Ouspensky, has a very vivid description in [1] of how focusing on two things at once leads to a changed state of consciousness, that seems like meditation, and comes from the saturation of the two streams of attention.

[1] https://en.wikipedia.org/wiki/In_Search_of_the_Miraculous

I believe this is why fugues are such a pleasure to listen to!

One of the first ways I learned to meditate/access different states of mind was a technique described as "overload trance" (IIRC). The premise was, listen to a piece of music, focusing on one musical component, then while keeping that focus, add another element, and another, etc.

It works best with pieces with a lot of ostinato (repetition/vamp) and Bach's Little Fugue in G minor was and is one of my favorites. Really fun to play too, though i get tripped up as soon as the feet get involved. Also, Utopia by Astral Projection (that whole album Trust in Trance 3 is great for this).

Bonus points to mentally visualizing something in time with the music (I like orbs whirling around like atomic orbitals). You can really tie up much of your mental processing this way and I find it much easier than traditional zen meditation, trying to bring focus back to eg. breathing.

Little fugue: https://youtu.be/ddbxFi3-UO4

Trust in trance 3 playlist: https://youtube.com/playlist?list=OLAK5uy_mHhgZDphEanJgP6zSz...

If you couldn't process multiple streams ( audio/visual/other senses ) how would you ever be able to monitor the background for danger and context switch?

There is a difference between conscious experience and what's going on in the background.

This is about multiple speech streams.

More specific from the mere ability to process multiple sensory streams in general.

Sure. Still don't see why the result is at all surprising.

If you couldn't process multiple streams ( I see nothing special about speech - note parsing speech is potentially different from thinking over the top - ie the difference between hearing and listening ) simultaneously it's hard to see how you'd last 5 minutes.

There’s a big difference between processing multiple streams, and processing multiple streams simultaneously.

You can achieve the former, without the latter, by doing time slicing. Spending a small amount of time processing stream A, then dropping that and processing stream B for a moment, then swapping back. Just like how a single core CPU can process multiple threads.

Proving the brain is continuously processing and encoding multiple streams simultaneously is an interesting finding that helps us better understand how our brains handle multitasking. That’s absolutely something worth studying and understanding, even if the headline discovery “feels” obvious. It the precise mechanism that’s interesting, not the effect the mechanism produces.

When I meditated a lot, I was able to sit in a cafe and listen to 3 conversations without switching and be able to understand them and remember them all. It happened to me few times. Also, once, sleeping in a tent, a voice from a dream interfered with sound of raindrops and became distorted and I woke up scared only to quickly get what just happened.

Not sure why you are downvoted. Well it probably doesnt require meditation because split attention is somewhat common here. My mother can follow multiple discussions like have a phone conversation and understand what I tell her. In general I can't.

So a bit harder for me. I can focus on work and follow some podcasts but not speak and at the same time listen to a full parallel convo.

I do believe brain to brain communication exists from experience too. People will be quick to call it schizophrenia and indeed it can be maddening because it evidently reuses your neurotransmitters for information propagation. That includes dopamine and can lead to the same issues some diagnosed people have, but actually a couple at the same time.

Without visual hallucinations but the brain gets a bit taken still, since it has to share processing. So it can induce adhd like symptoms, loss of phantasia, nucleus acumbens becoming nucleus incumbered :D, impaired motivation, etc.. But it is transient and you can argue it within yourself with some amount of relief. If you notice and start a loop of wondering where it comes from you are toast though.

Anyway, probably saying too much. You have to experience it. Probably someone playing with AI and neurochemistry. Still can't figure out the actual transport system. It does not make much sense from a wavelength point of view. Even if merely HF acoustic waves (since they can be more directed) not quite sure. Should ask whoever big galaxy brain created the havana effect... \sarcasm

At the same time people already know publicly how to decode brain signals and turn them into movements and Computer Interface actions. So the brain is not a complete blackbox. Some people might be further along...

Anyway... we will know eventually what is this all about..

likely related to how trained and some untrained dogs sense what you are up to consciously or not (yet).

brains smell/decode info that we don't have an actual odor (but receptors) for.

it's also why (some) pets and animals react to their human's mood/attitude and short-, mid-, long-term stress (and other) hormone levels.

some people get their energy drained by persons that they are not even aware of being in proximity (e.g. dad got home after work while child is wearing headphones). it can become a matter of good or bad resilience, too, and some brains can develop defence mechanisms by mere exposure while others can't, which is likely (definitely) entangled in/with hormone metabolisms.

I say this as someone recognizing myself: learn the real, detailed, mechanistic, intelligible science. The world does not work like sci-fi, despite how many people make claims that amount to as much (with 0 actual evident evidence). That is not to say that all there is is what’s readily apparent. But when you forgo that assumption, you have to be careful because it easily slips into ur own understanding of what “there is” becoming overly skewed towards things that are not apparent (read: the brain feeding into its own maladaptive patterns of connection, making up things and then falling into confirmation bias). Physical reality is the base, at least when regarding things practically.

Oh for sure, doing any otherwise would lead someone to psychosis very easily. Coming from a family of MDs and being educated in multiple scientific fields myself, I still don't have an answer. But one thing for certain, you have to disregard everything, including religious beliefs and go by the scientific method.

There are tell-tale signs that people will tell you to ignore like fasciculations (muscle twitching) noticeable with the naked eye which are a signs that neuro transmission is peaking more than normal (that would be glutamate-linked).

The problem is that people don't have an answer even after doing Root Cause Analysis. Leaves you like someone trying to explain how the sun looks to someone who is blind.

Occam's razor.

> Spending a small amount of time processing stream A, then dropping that and processing stream B for a moment, then swapping back. Just like how a single core CPU can process multiple threads.

The brain isn't a computer with a single CPU - just because computers are built that way doesn't mean the brain is.

Ie it's only surprising if you start with an erroneous computer based model of how the brain works.

The paper is interesting in that it looks at a core interesting issue - which is how conscious attention is managed given we know that behind the scenes it's 'everything all at once'.

There is also a different quality of processing. Textunderstanding and danger deciphering of signals.

Sure.

Have you ever listened to music while simultaneously writing a comment on hacker news - and managed the split cognitive load effortlessly?

No, have you ever assumed that everyone surrounding you is exactly the same because mirror-neurons? Because i never did that- i just know..

When I used to go to parties in college, I was known within my friend group for participating in multiple conversations at once, flitting from one group to another. One of my friends later told me he thought it was impressive, but in fact I just couldn't help but hear all of the conversations at once, and if multiple groups were talking about interesting things, I would find myself torn between them, and end up bouncing back and forth.

I had assumed this was already well known.

My issue is that I can't stop processing other speech streams. It seems other people can tune out conversations around them when talking to a person but I have to hear every word

Famously, the Apollo Mission control team learned to handle multiple conversations stream simultaneously. The side effect was that going to cocktail parties was a nightmare, because they couldn’t turn it off.

that's fascinating. Do you have any link to this tidbit?

Dinners with my extended family are like this (everybody talking at the same time, most people participating in two simultaneous conversations). After moving away for college, my sister would not talk during dinners when visiting because she found it took her weeks to get back out of the habit again.

Airport controllers (and similar positions for trains and metros) probably also suffer from this then

“Bilocation” was one of the legendary superpowers of Pythagoras (he was miraculously able to lecture in two cities at the same time).

Whenever I’m in multiple conversations at once in a social setting, I think of Pythagoras

This is maybe only tangentially relevant to the linked study, but I've noticed I can read aloud from a book on autopilot while thinking about other things or even thinking back on past conversations. I could not do this a few years ago, but now it happens on its own. I wonder how that relates to attention and speech streams

I experienced this too, when I started reading out loud more. At first, it was just that my eyes would scan ahead a bit from what I was saying, to help me get the right emphasis by knowing where the sentence was going. It felt like I had "handed off" saying the words out loud to a "subroutine", so my attention could be on what I was reading. Then that "readahead" extended to a whole sentence. And at that point it was like I was so far ahead of what I was saying that I had time to think about it a bit. And then at some point it was like the "reading the words" part got handed off to a "subroutine" too, so my attention could mostly stay on whatever I was thinking

This is something that has been studied and is apparently more common when reading out loud. I have this as well. I can read to my kids and at the same time plan the upcoming day. Pretty neat!

Sometimes I read a book out loud and think about something completely different.

I wonder if reading aloud might be like walking. I can be walking and speaking to a person at the same time.

Not reading out loud, but I've caught myself a few times on reading and not processing that, because I was thinking about something else. Like I still did the reading, but straight to /dev/null of my brain

I think everyone does this. It reminds me of a possible related phenomenon. The act of remembering what you do takes a few extra brain cells, to enable the “recording function “. If you are on complete autopilot, doing a routine task, you will often forget to turn on the recording function. Like the other day I tried to remember whther I had run the dryer and realized it had been completely optimized out of my memory.

I get that while driving home. I've driven half an hour and then realise I've been thinking about something else the entire time and cannot recall anything about the journey.

Welcome to a glimpse into the pathetic life [if one can even call it a life…] of a sad and wretched creature — the poor humans born with a deficiency of attention and an abundance of activity. This is a universal experience for the lost souls who stumble through life, burdened with a despicable and perverted simulacrum of a normal human’s brain, condemned with a condition more commonly known as…

The Dangerously Corrupted and Criminally Insane Mind of the ADHD Afflicted!

There is an interesting point about this from animation.

Imagine you are seeing a pendulum clock and it makes a "tick" on one extreme and "tock" on the other.

When they first started doing animation + sound they noticed that if you play the "tock" sound at the exact same time the pendulum hit the extreme, people would think it was delayed.

Research showed that humans required a small amount of time to "context switch" from one stimulus to another. I think it's about 1/16th of a second.

Some interesting other observations about time perception here: https://en.wikipedia.org/wiki/Time_perception

But the tick/tock on a real clock happens before the end of the swing anyway

sound is also slow

Anecdotally, I have 3 young kids who sometimes all talk to me at once. It's impossible to process, but with 2, I've noticed it IS kinda possible process.

ask any dj who doesnt use modern sync tools and they will tell u, u can follow 2 entire songs out of sync of eachother fine, it takes practice but your brain can get used to these kinda tasks. (ofc very unscientific here :D)

I’ve actually found that I’m able to process two speech streams and one music stream independently from those. At least for me, music seems to have a dedicated sub-processor of sorts.

Stuff like this is what makes me not worry about AI overtaking humanity. The human brain + mind is so sophisticated, we have no idea what untapped potential still remains.

And anecdotally, this headline feels like it's confirming something already well-known. I once did a presentation for a software team visiting the US from South Korea and their translator was real-time translating my words into Korean for them. The translator had an earpiece in and so did the clients. Once I adjusted to it, it became very natural to present and interact this way (but it was certainly weird at first).

I do a form of this all the time and I've always wondered "how." I can copy Morse Code--hearing the code and writing it down--while carrying on a conversation with someone else. I'm only "encoding" it, in that I have to read it to know what I just copied. The process of hearing a letter or word in Morse and moving my hand to write it has become so automatic that I can do it while having a live conversation with someone in the room.

It would be interesting to know what's going on in my head with an EEG or FMRI...

Then it is known that if you play to someone with small delay what he says he will be lost on both - so he can't think about and listen to what he is saying if it's not one stream.

Supported by the empirical evidence of cube farms, post COVID in the early “return to office” days, when office etiquette was completely forgotten and people were listening to all their meetings on speaker, but we were still having all our meetings at our desks.

I would constantly hear people around the cube farm stumbling through sentences because they could hear themselves through a neighbors computer with a slight delay.

Findings like these surprise me. I had a NDE a few years ago and my observation was such that everything slowed down tremendously and I was able to process every instant like it was slow motion. This wasn't like a "metaphysical" thing. I could recall the entire trip in the ambulance, every moment seemed like it was minutes.

We have so many "hacks" that the brain encodes to do the least work possible that I don't know if we could ever truly know what the brain would be capable of.

I read the paper's abstract. They're not actually claiming what commenters here think they are. They're saying that there's some sort of pipeline processing for the task of "listening to speech" and when the subject switches focus from listening to one speaker to another, that pipeline has to drain. And the new stream pipeline has to get loaded up. Not actually surprising when you think about how it would have to work. The same thing likely happens with vision.

I wonder if parallel processing is related to musical training or ability.

I've always been jealous of people who can play the drums and sing or play piano with both hands and a foot while singing.

I can do the music part just fine. But listening to two conversations at the same time just means I understand neither of them.

Anecdotal:

A long time ago, in my 20's, I found out it's easy for me to think in two streams as long as they operated in different languages. I could talk to my colleagues in Hebrew and answer emails in English at the same time.

Surprisingly, writing and speaking in the same language is not as easy for me. Possible, but requires some mental effort to keep the buffers separated.

Listening to two talkers at a time is certainly doable...

As is talking whilst listening to another conversation - eg. Giving a lecture whilst eves dropping on the people talking at the back of the lecture theatre.

However, having a two way conversation with one person whilst listening to another is really hard.

Not sure why.

Listening and responding are likely pretty different mental activities

I'm a native English speaking pinball freak living as an expat in a German-speaking country, and I find myself often listening to English speakers on the train, while also carrying on a conversation in German .. and I have observed that the same part of my mind that can handle multi ball-pinball events, where during a pinball session multiple balls are in play, 'feels' active.

Its a kind of context juggling mechanism in both cases, and it feels like the same mental muscle being exercised in both cases.

I wonder if there is a worthwhile experiment to be conducted wherein an EEG'ed pinball player gets to play pinball with easy multi ball targets, while also listening to German and English speakers, and then passing a test at the end of it .. because I sure have been preparing for that kind of scenario lately ..

You're using one of the streams for yourself. :P

Yes, and you can also write two different sentences using two different pens in your hands.

When my son was about 4 or 5 he used to draw pictures with pens in both hands simultaneously which I was always amazed he could do!

When I was an infant I'd waddle through my mothers garden to my favourite fruit tree... a chilly bush. I'd pick the red chillies and eat them with gusto. My mouth would turn red but that didn't bother me. These were very hot chillies that my parents couldn't eat even when they were green.

Sadly, I lost that super power at some point. I love a spicy curry, but I don't think I'd make it through a Hot Ones episode as a guest.

Does your son still have his ability?

And you can subvocalize (that is, think them in your mind) two different voices at once if you deliberately try to, and it's a skill that gets easier with practice. Though, no matter how much I practiced it, I was never able to get to where it would take place automatically without my forcing it.

My wife's brain could probably do that. I'm not so sure about mine.

Echoes of the bicameral mind[1]?

[1] https://en.wikipedia.org/wiki/Bicameral_mentality

you guys telling me you still listening to only 1 podcast at the time?

Left ear: Mozart, right ear: The Bible in Chinese

The simultaneous neural representation is very interesting result here

This seems potentially useful for attention-steered hearing aids. A system that waits for complete disengagement from the old speaker may react too slowly

I knew a few ham radio guys who could copy Morse code at greater than 20 WPM and simultaneously carry on a conversation.

"humans have only one language processor" -- this is what I remember from Patrick Henry Winstons lecture

Async-programming style single-core concurrency would still look like parallelism to an outside observer :)

The same is true for music, otherwise canons and polyphony wouldn't work.

That's not a good argument. First, music is not speech. It doesn't require linguistic processing. Second, you can hear chords instead of individual voices, so polyphony can be perceived as shifting harmony, and it usually is.

It's incorrect to reduce polyphony to just shifting harmonies. Harmony is of course the constraint but the whole point is about intertwined voices - various melodies that your brain can process simultaneously. Music is not speech, but it's not that far from the language as it seems in terms of processing. When you hear 2 melodic lines at the same time, you're brain needs to encode them separately, in a similar manner to parallel speech streams.

The argument is not about "is polyphony shifting harmony" but about "does the brain encode two or more separate signals for polyphonic music." There's nothing that prevents the brain from encoding the whole thing in one stream, and taking that apart at a later stage. E.g., it might code music like "G3 over F, F3 over F, Em, A3 over Em, B3 over Em, C#4 over A7, etc."

It's not that it has to be like this, just that a mere theoretical argument cannot exclude it. And even then, musical perception has basically no relation to language processing.

I'm not so sure it's just perception involved. You're going along a street and can hear a violin playing. A melody develops, you establish a sense of tonality, can predict next sounds maybe. And then you also make out a recorder. Another piece, totally unrelated harmonically. Another stream to process, I would assume a brain can handle it (at least a musical one should).

I agree that language processing is different, but some similarities do exist.

The DJ is explained.

Many dj mixers offer the option to split the main mix to one ear and the cue’d track to the other, i have never been able to mix like that, only with cue on headphones and main mix out in the room/monitors. Weird

Everyone can be different and that's ok.

I know dj's who can rarely hear the song that's currently playing, and only hear all the other songs that can play with it.

Experiencing music is the gift :)

Humans are born with two ears anyways, right?

Come on guys, the contribution of the research is that it made measurements of how the processing of multiple inputs is represented in EEGs, not whether or not we can handle multiple inputs. Stop acting snarky, it just shows you didn't read beyond the headline.

Of course, because we have two ears.

yep, my wife does this routinely

parents tend to yell at the same time and it needs simultaneous processing

Also explains why we like music with two simultaneous distinct sections (bass + the rest). One without the other doesn't feel as complete

This is a completely different phenomenon. Your ear/brain are tuned to rhythmic beats in the lower frequencies (footsteps). We're better at pattern recognition with the lower frequencies.

Also, our brains will encode the differences in registers to evoke emotion differently, which is often used by horror films to make a scene scarier[0]. Evolutionarily this is probably to detect screams or babies crying, a rustling bush, etc.

Speech encoding, at least per this article, has little to do with that. We don't have music encoding so much as we have pattern recognition, instinctual emotional respond to sound, etc.

Another great video about how music is perceived in animals is [1], just while we're on the topic.

[0] https://www.atlasobscura.com/articles/how-the-hidden-sounds-...

[1] https://youtu.be/0ZYhyewNQMo?is=0mWSRAzObOD2p32E

Your example is needlessly bleak, but in general: yes, we're a social species and being able to process multiple speech streams seems obviously pretty important in many social contexts involving more than two people.

Seems doubtful to me that there will be any hardware in our species specific to processing language. It's going to be the same basic hardware as Chimps. Whatever is going on that's related to us being a social species is all software.

Uh, there definitely is "hardware specific to processing language" for our species, they even have their own wiki pages[0][1].

And in general our brains differ significantly from that of a chimpansee. Human brains push neuron density to to absolute limit within the animal kingdom and have unique evolutionary adaptations that allow for it. As a result our species also has mental health disorders unique to us that seem to be cause by the neurons being pushed past that limit.

[0] https://en.wikipedia.org/wiki/Wernicke%27s_area

[1] https://en.wikipedia.org/wiki/Broca%27s_area

If you can listen to someone play the piano with two hands, it’s a short hop to get to speech.

Not really (except perhaps if it's Stockhausen they're playing). A piece of music played with two hands is still one coherent information stream.

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