
Our Brain Uses a Not-So-Instant Replay to Make Decisions - prostoalex
https://www.scientificamerican.com/article/our-brain-uses-a-not-so-instant-replay-to-make-decisions/
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rjf72
Often when I read papers on neuroscience, I find it difficult to dismiss an
analogy. It feels much like we're trying to analyze how different models of
computers work by giving them all some input and then trying to discern
meaning from the circuitry that then activates in response. The problem with
this is imagine I give you even the precise specs of a fairly basic computing
system. You're going to be able to create a lot of correlations, yet you'd
probably make effectively 0 meaningful progress towards 'cracking' the system,
or really gaining any meaningful degree of insight beyond repeating
correlations. E.g. it may be that if you press the 'f' key, a certain area of
your circuit board sees a heat spike but that doesn't really tell you much of
anything. And, at worst, can give you false leads as you start to draw
correlations such as 'ahh!!! it heats up when I press f, g, and h, but not i,
j, k!!' When the actual reason, as is easy to imagine, might be entirely
spurious.

And in this case the analogy is many orders of magnitude worse. The brain is,
by far, the most complex computing system we know of. And instead of precise
specs, you have nothing but previous correlations to try to even have a clue
as to what you're studying. And even of the specs we can measure, it's not
looking hot. The Openworm [1] group for instance has been trying to model a
worm brain. The roundworm brain is about as simple as you can get: 302
neurons, 7,000 synapses. The human brain's at 86 billion neurons, 100 trillion
synapses. Yet even that worm project seems to have hit some unforeseen hurdles
since it appears to have stalled out since making headlines some half a decade
ago.

Of course neuroscience is far from my specialty, and it's entirely possible
I'm missing some critical nuance. I'd love to know why this analogy is
inappropriate if anybody could share.

[1] - [http://openworm.org/](http://openworm.org/)

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divan
> It feels much like we're trying to analyze how different models of computers
> work...

There is a paper on exactly this case - "Could a Neuroscientist Understand a
Microprocessor?". Great read.
[https://journals.plos.org/ploscompbiol/article?id=10.1371/jo...](https://journals.plos.org/ploscompbiol/article?id=10.1371/journal.pcbi.1005268)

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hacker_9
Wow that was an eye opener to the state of the field, thanks for posting!

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woliveirajr
So not only the physical repetition of an activity makes it perfect, and not
only replaying it mentally with eyes closed, but also dreaming of it...

It's the common sense being proven right, thus reinforcing how to improve it.

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SubiculumCode
I wish i wasnt on a nokia feature phone or id go into depth on the
misunderstandings u state about memory, the hippocampus, and the utility of
repetition as a mnemonic. Perhaps another memory researcher can in my place,
as it has taken me a while to type this already on this old style phn keyboard

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SubiculumCode
Example. Repetition least advanced mnemonic. Better: integration concepts and
rich imagery. Neuro replay not likely analogy 4 repetition mneumonic.
hippocampus fast learn, cortex slow learning, hip replay trains cortex to
remember and cortex integrates with other learned

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whatshisface
Your comments are almost impossible to understand. It might be nice if you
found a computer to type them on.

