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The overfitted brain: Dreams evolved to assist generalization

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Re: The overfitted brain: Dreams evolved to assist generalization

#71

Post by tgv »

azeirah wrote: post #23
babelfish wrote: post #21

> Sleep loss, specifically dream loss, leads to an overfitted brain that can still memorize and learn but fails to generalize appropriately Curious where this claim came from. Obviously a lack of sleep will degrade your day-to-day performance, but I almost never have dreams.

From what I recall, everybody dreams an approximately equal amount of time every night, the only major difference is how much of it is forgotten when you wake up. I wish I recalled (..or saved) the paper, but waking up releases a chemical in the brain that makes you actively and quickly forget what you just dreamed about.

Without very, very strong evidence, that's BS, or more politely put: a retroactive fit of the concept to the operationalization, in this case probably the REM observation which vaguely correlates with dreaming.

Re: The overfitted brain: Dreams evolved to assist generalization

#73

Post by toxik »

boardwaalk wrote: post #26
toxik wrote: post #25

Earlier quoted context omitted.

And if the brain is overfitted, how can it generate out-of-distribution samples? Seems like wildly cyclical reasoning.

How can computers calculate more accurately than the human brain but also have PRNGs or even true hardware RNGs?

But that’s the thing, it’s NOT random. It’s just unlikely scenarios. Dreams still follows the general model of the world.

Re: The overfitted brain: Dreams evolved to assist generalization

#74

Post by jtsiskin »

elliekelly wrote: post #56
maxrev17 wrote: post #12

Read something recently theorizing dreams are to prevent the visual processing part of the brain from being repurposed when we sleep...

Can you explain what that means? Being repurposed for what and why would that be something we’ve evolved to avoid?

Bitcoin mining

Re: The overfitted brain: Dreams evolved to assist generalization

#76

Post by benp84 »

elliekelly wrote: post #56
maxrev17 wrote: post #12

Read something recently theorizing dreams are to prevent the visual processing part of the brain from being repurposed when we sleep...

Can you explain what that means? Being repurposed for what and why would that be something we’ve evolved to avoid?

It's like how the visual neurons of blind people get repurposed for other senses. Turns out this happens so quickly we can start to lose visual function in just the 8 hours our eyes are closed while we sleep.

Can't remember source but heard this theory on a podcast.

Re: The overfitted brain: Dreams evolved to assist generalization

#77

Post by t-writescode »

canjobear wrote: post #53
t-writescode wrote: post #18

I find it fascinating how a strong atheistic perspective and premise still tries to ascribe meaning to things. “Evolved to assist” and also most of the comments here that aren’t discussion of noticing animals dreaming.

There's nothing contradictory about using teleological language to describe evolution. Evolution is an algorithm that maximizes fitness in a changing environment over time. It does things "in order to" maximize fitness in the same way that you or a robot might do things "in order to" maximize utility.

Evolution is an algorithm that carries on traits that happened to be carried along when someone successfully mated. It speaks nothing of ‘fitness’ in any useful sense beyond ‘was successful at mating’.

It _tends_ to yield things that correlate well with survivability to time of mating; but to imply anything of intent to it is inaccurate and ascribing purpose where there is none in this model.

Re: The overfitted brain: Dreams evolved to assist generalization

#78

Post by kayamon »

wiml wrote: post #57
canjobear wrote: post #54

These theories are fun, but has it been shown that dreaming is an essential part of the function of sleep? If you could suppress dreaming but maintain sleep, would organisms still get the same benefit? Maybe what is required is simply a period of inactivity, and dreams are the effect of white noise cascading through the brain during that period.

From what I remember, all of the phases of sleep are essential — if you suppress any of them, the person becomes unwell (possibly even dies). That includes the REM phase in which we sleep. I don't know if you can arrange to have healthy REM with zero dreaming, though.

I used to dream a lot; in the past year since I started taking THC as medication I haven't had any. I put this down to the THC basically letting you dream while you're awake, which seems to be more effective than doing it while asleep. As far as I can tell the purpose of dreams seems to be a way for the brain to visualize its own structure and repair itself (i.e. retraining your pattern matching on other inputs, not just visual).

Re: The overfitted brain: Dreams evolved to assist generalization

#79

Post by canjobear »

t-writescode wrote: post #77
canjobear wrote: post #53

Earlier quoted context omitted.

There's nothing contradictory about using teleological language to describe evolution. Evolution is an algorithm that maximizes fitness in a changing environment over time. It does things "in order to" maximize fitness in the same way that you or a robot might do things "in order to" maximize utility.

Evolution is an algorithm that carries on traits that happened to be carried along when someone successfully mated. It speaks nothing of ‘fitness’ in any useful sense beyond ‘was successful at mating’. It _tends_ to yield things that correlate well with survivability to time of mating; but to imply anything of intent to it is inaccurate and ascribing purpose where there is none in this model.

> It speaks nothing of ‘fitness’ in any useful sense beyond ‘was successful at mating’.

That's the definition of fitness.

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

Re: The overfitted brain: Dreams evolved to assist generalization

#80

Post by t-writescode »

canjobear wrote: post #79
t-writescode wrote: post #77

Earlier quoted context omitted.

Evolution is an algorithm that carries on traits that happened to be carried along when someone successfully mated. It speaks nothing of ‘fitness’ in any useful sense beyond ‘was successful at mating’. It _tends_ to yield things that correlate well with survivability to time of mating; but to imply anything of intent to it is inaccurate and ascribing purpose where there is none in this model.

> It speaks nothing of ‘fitness’ in any useful sense beyond ‘was successful at mating’. That's the definition of fitness. https://en.wikipedia.org/wiki/Price_equation

And yet this still speaks nothing to the 'purpose' implied by so many. Even the article says it's a statistical reality and nothing more.
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