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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

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

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.
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.
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.
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.

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

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.

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.
“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
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

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)
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...

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.

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.
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.

This makes me wonder how much of paying attention is really prioritization rather than filtering everything else out. We probably process far more than we're consciously aware of.
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.

Yes, and you can also write two different sentences using two different pens in your hands.
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?
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
The same is true for music, otherwise canons and polyphony wouldn't work.
The DJ is explained.
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
If you can listen to someone play the piano with two hands, it’s a short hop to get to speech.