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

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61–70 of 193 posts

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

#61

I'm sure there is brain activity that prepares the baby for birth, but calling it a "dream" is just clickbait

I guess the suggestion that fetuses might dream probably seems outlandish if, for some reason, you were already committed to the idea that fetuses are "not alive."

They are all a stage of human life. I love the fact that they start learning languages before exiting the womb… Life is awesome!

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

#62
post #57
post #37

Earlier quoted context omitted.

Babies can't even roll-over until 4-6 months

Newborns have some ability to roll over that is lost and then regained, so it's not that they are physically incapable of rolling over.

I think the problem is they lose a lot of weight early on (can roll over) and then begin to fatten up quickly. The calorie intake relative to body size is immense and for a few months a baby just doesn’t have the muscle strength to support its newfound fat composition (loss of ability to roll) in addition to their heads growing rapidly early on and not having the neck muscles developed yet.

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

#64
post #12

Something about this reminds me of the 'Winning Ticket Hypothesis' in artifical neural networks: that some 'random' initializations prime a network far better for later faster learning. From https://arxiv.org/abs/1803.03635 - the abstract: Neural network pruning techniques can reduce the parameter counts of trained networks by over 90%, decreasing storage requirements and improving computational performance of infere…

How hard would it be to find random networks that don't need to be trained at all?

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...

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

#66
Really fascinating. Does this mean the world "view" is encoded into the DNA somehow and that then gets transformed into neural activity? How could a few billion pairs of acids encode such a world?

What's even more fascinating is that emotions, behaviors, imagination and dreams must all be encoded and not learnt with just a billion-odd pairs / bits.

Meanwhile, it takes a few megabytes for us humans to encode a decent Hello World program in a modern programming environment.

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

#67
> Crair said. “It’s like dreaming about what you are going to see before you even open your eyes.”

Given that we don’t know what dreaming is, that analogy adds unnecessary confusion to interpreting the phenomenon described in TFA.

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

#68
post #23

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 that cannot mature due to birth canal constraints I strongly doubt that human babies are physiologically capable of walking before 6-9 months regardless of their level of brain development. The entire baby is born many months "early" compared with other mammals due to the limitations of the…

This person's baby walked at 8 months [1] [1] https://www.scarymommy.com/complete-shock-early-walking-baby...

Hence me giving a range of 6-9 months. My niece was walking not long after 9 months, it's rare but not unheard of. A newborn baby simply wouldn't have the physical strength or rigidity, though.

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

#69

I'm sure there is brain activity that prepares the baby for birth, but calling it a "dream" is just clickbait

I guess the suggestion that fetuses might dream probably seems outlandish if, for some reason, you were already committed to the idea that fetuses are "not alive."

Are you thinking about zygote rather than fetus perhaps?

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

#70
post #12

Something about this reminds me of the 'Winning Ticket Hypothesis' in artifical neural networks: that some 'random' initializations prime a network far better for later faster learning. From https://arxiv.org/abs/1803.03635 - the abstract: Neural network pruning techniques can reduce the parameter counts of trained networks by over 90%, decreasing storage requirements and improving computational performance of infere…

> 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…

> this is commonly attributed to the fact that human babies have immature brains that cannot mature due to birth canal constraints, which is constrained by pelvis size which is constrained by the need to walk upright

Interestingly, the EGG hypothesis postulates that the constraining factor is not pelvis size, but rather that neonates consume so much energy that we give birth just before a women's metabolic limits would otherwise be overrun (leading to both maternal and infant death). Based on this, the increased energy demands of our larger brains mean that we have to sacrifice neonatal motor skills or drastically improve the metabolic efficiency of adult women.

https://www.pnas.org/content/109/38/15212

> In humans, maximum sustained metabolic rate is thought to be 2.0–2.5× basal metabolic rate (BMR).

> By 9 mo, metabolic demands of the fetus threaten to push maternal energy requirements beyond 2.1× BMR. Extending gestation by even one month would likely require metabolic investment beyond the mother’s capacity. Instead, the mother delivers and the neonate’s growth rate slows relative to its fetal growth rate, keeping both the offspring’s and the mother’s energy requirements in check.

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