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Human brain compresses working memories into low-res ‘summaries’

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211–220 of 349 posts

Re: Human brain compresses working memories into low-res ‘summaries’

#211
post #190

Earlier quoted context omitted.

I know this is a joke but it seems unnecessary. Most people actually do use evidence and logic to arrive at their opinions. The problem is some people are presented with incorrect or fabricated evidence. Some people draw incorrect conclusions, or maybe some of the evidence is above their head so they ignore that when it's vital to proper understanding. Some people aren't particularly good at logical thinking, or neve…

> Most people actually do use evidence and logic That's not how humans function. They are social animals and copy the opinions and beliefs of those they want to be (stay) friends with. Being part of the group is what matters, evolutionary, not logics and being right. And to influence others, step 1 is to make them look at you as a friend. There's a book about that :-)

“Man is not a rational animal; he is a rationalizing animal.” -- Heinlein

Re: Human brain compresses working memories into low-res ‘summaries’

#212

Earlier quoted context omitted.

It offers a one-to-one correspondence between stimuli and classifications, what else could a definition be?

Definitions ideally don't require an oracle.

How then do you define Pythia?

Re: Human brain compresses working memories into low-res ‘summaries’

#213

Earlier quoted context omitted.

Bread is defined as anything I think bread is, and the same goes for any other word. To hold another position would be in some way dishonest.

That makes you a bread-oracle O, but doesn't define bread. Since there are some inputs x where O(x0) = False, some where O(x1) = True, and the laws of physics are continuous(yes, even in quantum mechanics), Buridan's Principle implies that you are incapable of deciding the breadness of arbitrary input in bounded time.

I don't think this is true? Suppose I define "bread" as "that which has a net positive charge" [1]. Can I not put the bread candidate in an electric field in flat spacetime and measure (the direction of) its acceleration in a bounded time? I suppose I might be depending on its mass being finite, but the observable universe supports that assumption.

[1] I don't think this is a very useful definition of bread.

Re: Human brain compresses working memories into low-res ‘summaries’

#215
> To take a closer look, they used a sophisticated model that allowed them to project the three-dimensional patterns of brain activity into a more-informative, two-dimensional representation of visual space. And, indeed, their analysis of the data revealed a line-like pattern,...

So are they reading their minds? Is that possible/ What does it look like?

Re: Human brain compresses working memories into low-res ‘summaries’

#216

I think this is why it's hard sometimes to argue in support of something you believe, even if you're right. At one point, all of the relevant facts and figures were loaded into your working memory, and with that information you arrived at a conclusion. Your brain, however, no longer needs those facts and figures; you've gotten what you needed from them, and they can be kicked out of working memory. What you store the…

Interesting thought. Perhaps that is also why people sometimes have a hard time changing their mind when confronted with new information: a certain number of bits of information have led you to your belief, and even if some of those change or turn out to be false, you can't access those bits anymore individually, but only the resulting belief.

Perhaps, the more those beliefs are reinforced, the less likely you are to access it's constituents. Sounds a lot like inductive bias, but somehow different from ML.

Re: Human brain compresses working memories into low-res ‘summaries’

#218

It all works this way (though a certain female family member would disagree, claiming to remember conversations word-for-word years later). But my memory works this way. A summary "party at so-and-so's house, weather was nice, overall vibe was ___". The rest is context. You know what the house/backyard is like, you know the general feel of that time of year, you know the crowd that usually comes, you can easily synth…

I think some memories are closer to lossless compressions than lossy which I wonder if it's more of a scale where memories can slide between the two modes with varying degrees of fidelity. Like there are memories that I know I shouldn't remember from childhood that I can remember clearly and others I barely remember what year it happened. So I have to wonder if some of this seeming lossless-ness is more fractal-like…

If you are taking a truncated SVD, the math says that it is the best representation of that data for a given truncation size, and will even give you a measure of how good that representation is. But picking how good you need often ends up being a kind of annoying and fuzzy heuristic thing. In addition, some data just gives you better singular values, and so fundamentally compresses better.

I guess the brain probably is dealing (in a hugely non-mathematical way -- it is just an analogy!) with a similar sort of thing. Somehow we pick some memories to keep in great detail -- either because they seem to be very valuable, or because they just seem to compress nicely.

It is a bit funny that one name for this sort of thing is a "singular experience."

Re: Human brain compresses working memories into low-res ‘summaries’

#220
post #190

Earlier quoted context omitted.

>At one point, all of the relevant facts and figures were loaded into your working memory, and with that information you arrived at a conclusion You are awfully optimistic about the rationality of humans, aren't you? :)

I know this is a joke but it seems unnecessary. Most people actually do use evidence and logic to arrive at their opinions. The problem is some people are presented with incorrect or fabricated evidence. Some people draw incorrect conclusions, or maybe some of the evidence is above their head so they ignore that when it's vital to proper understanding. Some people aren't particularly good at logical thinking, or neve…

"Most people actually do use evidence and logic to arrive at their opinions."

They do not. The brain is a machine of lies designed to keep you alive, rather than arrive at some pure truth. The vast majority of your brain power is subconscious. Your brain is extremely good at arriving what it needs to know, not at knowing or truthfulness in general.

It takes an incredible effort in critical thinking (which does not come natural) to unravel the layers of misdirection and crap your brain has produced in order to come to a kind of objective truth. It's such a headache inducing process that few will undertake it. Even more so when the outcome of critical thinking is typically uncomfortable.

Perhaps more unsettling is that even the very concept of you is a lie. Not your body, obviously. Your inner self, your identity if you will. You think you're some kind of well defined, consistent character. Carved in stone. One could perhaps summarize you in 10 bullet points and this idea of you is pretty stable over time. That's how you know it's you.

In reality, the brain has established this concept of you because it's in your best interest. Every little piece of input, thought or memory that directly contradicts it (which is constantly) is carefully dismissed whilst the confirmation of the false belief is amplified. Not because it is correct, because it is preferential.

I'm happy to leave you in this confused state on a random Tuesday. You can now think that this guy is full of shit, which proves my point of your brain filtering information that is not in your best interest. Or, you can agree. The outcome is the same. I'm right. Or, rather, my brain thinks it is. Which is what brains do. It's a defensive organ.

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