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Mammals dream about the world they are about to experience before they are born

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Re: Mammals dream about the world they are about to experience before they are born

#101

Post by freemint »

emmelaich wrote: post #44
chrisseaton wrote: post #26

Earlier quoted context omitted.

> Most human babies take 9-18 months to walk, and this is commonly attributed to the fact that human babies have immature brains Have you ever seen a new-born baby's legs? They aren't even remotely strong enough to walk, no matter what the brain tells them. It takes those months to develop leg muscles. New-borns don't have them. It's absolutely not restricted by the brain size.

Well, the legs may be less developed since they're not useful because ... the brain size is not big enough? Anyway, hard to conclude, just think your logic is missing a little.

Or maybe it's not the brain is to small, but that the brain is still growing and therefore subject to enough noise to make actions now impossible for the sake of the future.

Re: Mammals dream about the world they are about to experience before they are born

#102

Post by freemint »

CaptainNegative wrote: post #85
AnIdiotOnTheNet wrote: post #64

Earlier quoted context omitted.

Depends on the size of the network I would guess. A Boltzmann brain would apparently take about 10^10^50 years to form from quantum fluctuation in a vacuum. Our hypothetical neural network would be less complicated than that, assuming we're not aiming for general AI, so I think we can safely take that as an upper bound...

With a uniform initialization, presumably you'd never need much more than 2^(network bit complexity) number of samples to come across an ideally-initialized network with decent probability, so that's 2^10^24 for anything that fits in a yottabyte.

In the absence of dynamics and uniform random mutation, yes. But Both don't hold in the universe.

Re: Mammals dream about the world they are about to experience before they are born

#104

Post by system2 »

shannifin wrote: post #81

> A new Yale study suggests that, in a sense, mammals dream about the world they are about to experience before they are even born. "In a sense" ... A bit of a click-baity title for what amounts to suggesting that brain wiring is primed for sensing the world, which is not news. The study itself looks to be more about how the brain primes itself (visual systems specifically). It may or may not have anything to do with…

People do not read without click-bait anymore.

Re: Mammals dream about the world they are about to experience before they are born

#105

Post by tigershark »

afavour wrote: post #60
teruakohatu wrote: post #17

Earlier quoted context omitted.

> Are these innate patterns of activity priming mammalian brains in a similar way? A newborn foal can stand within 55 minutes of being born and can walk or run within 90 minutes. That is crazy fast training speed. Is it training initialization or is it a form of transfer learning? Most human babies take 9-18 months to walk, and this is commonly attributed to the fact that human babies have immature brains that cannot…

Perhaps only partially related to what you're saying but human babies are born with some innate reflexes: https://www.stanfordchildrens.org/en/topic/default?id=newbor... Perhaps the most relevant to this discussion is the "stepping" reflex. It isn't really stepping but if placed in a standing-like position babies will often raise one foot, put it down, then the other. The most interesting part to me is that this refl…

They can even swim safely underwater thanks to a reflex.

Re: Mammals dream about the world they are about to experience before they are born

#106

Post by yellowapple »

Geee wrote: post #88

Is it possible that there's some kind of neural transfer from the mother's brain during pregnancy? I've been wondering if there is or if it's all genetic. Evolutionary it would be very interesting if consciousness wasn't genetic, but transferred during pregnancy.

I'd be pretty curious about the mechanism for such transfer. The umbilical cord doesn't contain nerves AFAIK (and even if it did, the whole point of placental reproduction is to isolate the embryo/fetus from the mother, so probably no nervous connection there, either), so that'd preclude a direct connection between their nervous systems. Maybe hormones or some other chemical means?

Re: Mammals dream about the world they are about to experience before they are born

#107

Post by l33tman »

afavour wrote: post #60
teruakohatu wrote: post #17

Earlier quoted context omitted.

> Are these innate patterns of activity priming mammalian brains in a similar way? A newborn foal can stand within 55 minutes of being born and can walk or run within 90 minutes. That is crazy fast training speed. Is it training initialization or is it a form of transfer learning? Most human babies take 9-18 months to walk, and this is commonly attributed to the fact that human babies have immature brains that cannot…

Perhaps only partially related to what you're saying but human babies are born with some innate reflexes: https://www.stanfordchildrens.org/en/topic/default?id=newbor... Perhaps the most relevant to this discussion is the "stepping" reflex. It isn't really stepping but if placed in a standing-like position babies will often raise one foot, put it down, then the other. The most interesting part to me is that this refl…

These primal reflex arcs are suppressed by pyramidal circuits from the brain as they mature, essentially overriding them. This is one set of neurological tests of damage to the higher spinal cord/brain in adults; those reflexes can re-appear due to again limited inhibition.

Re: Mammals dream about the world they are about to experience before they are born

#108

Post by hypertele-Xii »

rudyfink wrote: post #35
sjg007 wrote: post #33

Do they do this in the dark and is it correlated with light input.. so is the eye/brain responding to stimulus even though the eyes aren't open yet?

I recall once hearing a talk that discussed, what I recall as, "test patterns" being run across the visual cortex prior to birth. Essentially, waves / patterns of stimulation would go across the optic structure that would be used to, again as I recall it, "calibrate" the visual system. I dug a bit and was able to find this paper https://pubmed.ncbi.nlm.nih.gov/15289028/ , which seems to track my memory. It has a numb…

Are these the same patterns one can see by applying pressure on the inner corners of the eyes? Massaging my tear ducts makes me see strange black/white/gray/color patterns that change over time.

Re: Mammals dream about the world they are about to experience before they are born

#109

Post by l33tman »

To put this into context, retinal waves (essentially self-propagating excitations along the retina) pre-birth have been known to exist and help neural organization for what must be 20-30 years. What's new in this paper is that they additionally confirmed that the direction of the propagating waves coincided with the mouse's typical optical flow pattern, essentially helping priming motion-detection neurons in addition to the well-known edge-detection neurons early.

I wouldn't compare this to dreaming really, it's a very different process where top-down connections hallucinate sensations. This is a completely bottom-up process, it's more or less like a test-bench connected to the optic nerve generating moving edges pre-birth.

Re: Mammals dream about the world they are about to experience before they are born

#110

Post by adamauckland »

underwater wrote: post #55
throw_nbvc1234 wrote: post #46

Earlier quoted context omitted.

Except that children can walk with assistance (and crawl) before they're strong enough to walk on their own.

Interestingly they can also effectively communicate well before they can vocalise words. A baby can sign reliably at 7-9 months but typically won't be able to speak until 12 months.

'Walking by one, talking by two'
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