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Comment by rhombocombus | Hacker News Reader

There is a big difference between multitasking and parallel processing. As a former neuroscientist I get rankled when I read gross conflations like this, it doesn't help anyone understand how the brain actually works, nor does it effectively underscore the attentional drawbacks of trying to multitask.

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The brain is more like SIMD than multicore processing, but I think a better analogy is a FPGA; it can do heterogenous instructions, but switching from one task to another is a crushingly expensive stop-the-world affair.

Possibly people assume that they are conscious of all the tasks that their brain does?

Can they walk and chew gum?

You are conscious of most things your brain does. Background tasks like walking and chewing gum tend to be very rote and decision light. Try and write while listening to someone speak, fold a paper airplane while navigating a new city, or program while watching a film.

Writing, listening, watching a film and navigating a new place all require attention as they're novel activities. But I could easily make a shit paper aeroplane while navigating, and I've coded through pure muscle memory plenty of times. Almost any activity can be internalised.

> I've coded through pure muscle memory plenty of times

How many lines of code though? :D

Couldn't tell you, wasn't paying attention ;)

I'd call it more similar to a computer system with multiple specialized processors working in parallel and limited buffers between them. Parallel system, really, not multithreaded.

All mostly stuck on a single bus and constantly blocking.

Fellow former neuroscientist here! The proliferation of pseudo-neuro explanations and analogies is infuriating. I envy people like theoretical physicists who work in a field where laypeople don't feel like they have an intuitive understanding of their subject area.

Maybe you haven't noticed how "quantum" is being thrown around these days, check https://en.wikipedia.org/wiki/Quantum_healing and https://en.wikipedia.org/wiki/Quantum_mysticism

I for one am a specialist on quantum mechanics since I read Steven Hawking. It's all bonkers, I can tell you that, but because of the uncertainty principle, I'm not really sure. That's OK because there is some parallel world in the multiverse in which it isn't. And please don't ask me to explain, I've read enough to know that by Hoffstadter's Incompleteness theorems I cannot prove it.

I know that dog created the universe with a pair of parentheses and after that it was pretty much backwards and uphill.

ok maybe not: https://xkcd.com/224/

I remember Richard Feynman (a theoretical physicist) explaining how you could deduce things about the human mind by observing behavior and self-reported internal states.

I really wish there were more books for laypeople by neuroscientists. I don't care much for theoretical physics personally, but a lot of people want to understand their own brains.

> lot of people want to understand their own brains.

You are what you think. I have no idea how or why... but I know this is so.

>You are what you think. I have no idea how or why... but I know this is so.

Given the evidence that conscious thought, self-awareness and "free will" are post-hoc effects, emerging after decisions are made by the brain at a subconscious level, it's more likely that that you are what thinks you.

I gather there is some debate in the field as to whether this is a true effect or a consequence of bad measurements. I do find it fascinating and await better evidence before making my mind up either way.

I do, however, appreciate your splendid and witty statement and shall reward you with an upvote :-)

> Given the evidence that conscious thought, self-awareness and "free will" are post-hoc effects, emerging after decisions

But I thought I was a racer from age 6... and now I are one.

Former physicist here! Hearing people talk about vibrations, entanglement, dimensions, quantum and other specific terminology in a more or less woowoo/spiritual context is just as infuriating.

Fiction writer here. If I had a penny for each time one of my readers asked, "So did they go to another dimension?"...

I think a better analogy is the way GPU calculations are done, as the calculations are done in parallel but the process is ultimately sequential: move data from CPU RAM to GPU RAM, calculate in parallel on GPU, move results data back to CPU RAM, operate on the results data on the CPU serially.

True, but from a big-picture view he might be doing a better job explaining the concepts to laypeople. And in that it might help them improve how they work / live :)

Sure, the layperson knows what multi-threading is.

The lay hacker.

But isn't the brain massively multitasking? It controls and keeps track of an awful lot of stuff. The "can't do multiple things [well] at once" really just applies to conscious efforts.

It is, but that's not what the article is about.

Maybe he meant the conscious mind we experience abstractly and is somehow hosted in / by the brain.

In which case, sure, it makes sense that each thought blocks the main thread and that's why thought-loops are particularly annoying.

In terms of I/O though, I certainly try to optimize the main thread with concurrent patterns when the input queue gets hit with high traffic. Even if I'm recurrently mulling over something for days, hoping for a break-through or insight or whatever, it's not like I'm incapacitated and can't perform / prioritize other thoughtful tasks on the event loop.

The keyword in the previous person's comment is attention. It's attention that is incapable of multi-tasking. It really just bounces from one thing to the other and attention is sort of what drives consciousness and directs it where to go. But the rest of the brain is doing a ton, such as memory encoding to both working and long-term memory. It's also doing things like language, motor, emotional processing, etc. as well as all the things more peripheral to consciousness like senses, time, vitals, etc.

If we look at the brain like a computer that interacts with the world as well as interacted with, I like to imagine that the brain is very complex and running many parallel processes. Like a computer, it has many parts of the interface to the world. Eyes are the screen, ears are the speakers, muscles are the mouse and keyboard, etc. I like to think of attention as the cursor; sort of a single process that directs what the user is interacting with.

I'm positive that is much too simple of an analogy because it still leaves the question: why can't consciousness control multiple attention cursors simultaneously? In many ways, it does in which consciousness can pass things off to automatic processing, like triggering muscle memory and other previously strengthened pathways. But, I think the why there's not multiple attention processes running is still a big question yet to be answered. I think neuroscience still has a lot to be understood before we'll be able to answer it sufficiently.

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