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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

#51

Post by Davidzheng »

euske wrote: post #7

I always wondered how our brain is pre-wired to recognize 3D objects right after a birth, but this article is saying that eyes are giving fake image-like input to our brain so that it can perform "pre-training"? Does this imply that our brain is truly a blank slate if these initial seeds aren't given?

sorry but I don't think there is any sense in which the infant brain is a blank slate. Definitely not for vital functions (as seen by the "instinctual" abilities noted elsewhere in this thread, not in language/cognition, and IMO not even culturally/morally.

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

#52

Post by jvanderbot »

teruakohatu wrote: post #17
gojomo wrote: 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…

> Is it training initialization or is it a form of transfer learning?

I doubt it's randomly initialized. The brain has centers for motion which might be honed in at birth for these animals.

Let's not ignore genetics, which pre-populate weights and subnetworks in the form of motion-control centers in the brain. Once you consider the gene-brain interaction over the course of evolution as part of your training, the huge data required for modern ML starts to make more sense.

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

#53

Post by narag »

chrisseaton wrote: post #26
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…

> 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.

It's absolutely not restricted by the brain size.

The brain size needs a huge head, so in a sense it is.

All the factors are interwined. The growth of the brain seems to have been a very fast evolution, The pelvis had no time to adapt, so giving birth early was the final solution.

With that in mind, I don't find fair to shame the pelvis, or the brain. The weakest link is the legs, but it's not their fault either since they had no time to mature.

Give one of those cocky foals a head of proportional weight and allow them to use only two limbs and see who's stumbling now!

Edit: newborns can't even balance their heads on their necks, they're extremely fragile.

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

#55

Post by underwater »

throw_nbvc1234 wrote: post #46
emmelaich wrote: post #44

Earlier quoted context omitted.

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.

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.

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

#56

Post by dogorman »

stevenhuang wrote: post #42
dogorman wrote: post #36

Earlier quoted context omitted.

I've found that "fetuses aren't alive" is a common talking point espoused by people who aren't comfortable sitting in a moral gray area and want an simple excuse to resolve their cognitive dissonance. It's common enough that I can't help but wonder if that is the reason people are so resistant to the idea that fetuses might dream. It seems remarkably similar to "farm animals can't feel pain" . A transparent fib peopl…

I think you've confused the talking points. I've heard the saying that fetuses aren't conscious , but I've never heard anyone, however fringe, say fetuses aren't alive .

Maybe so, though this too seems like a strange belief, and touches on the reason I find surprise at such things odd: it's been known for years that fetuses at late stages have cycles of REM sleep and apparent wakefulness.

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

#57

Post by amock »

phire wrote: post #37
taneq wrote: 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…

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.

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

#58

Post by briefcomment »

taneq wrote: post #23
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…

> 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...

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

#59

Post by teruakohatu »

retrac wrote: post #31
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…

> That is crazy fast training speed. Is it? If we ignore compute requirements, how long would a good algorithm take to learn something like balancing a quadrupedal robot, based on real-time feedback to its outputs? It is a simpler problem, but drone flight software based on learning, can re-learn how to fly a quadcopter after something like losing a propeller and a sudden shift in weight distribution, in a few second…

> Is it? If we ignore compute requirements, how long would a good algorithm take to learn something like balancing a quadrupedal robot

Seems easy but why don't we have self driving cars by now?

Walking it not just a mechanical task. Your quadcopter is not learning to interpret raw electrical signals from an IMS and raw electrical signals from a CMOS sensor. The training is also probably done in a simulator, where if it breaks, it is reset and training continues.

A horse is learning to interpret inner ear signals and signals from the optical nerve AND the using those to build a spatial map of the environment. Only then it is actually trying to walk.

A 2 hour old baby horse can not only run on not-flat terrain but is spatially and environmentally aware. It has taken years for Boston Dynamics to develop a platform that is equivalent to a pack horse and even then probably can't respond independently to never-seen-before threats or challenges.

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

#60

Post by afavour »

teruakohatu wrote: post #17
gojomo wrote: 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…

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 reflex stops by two months. Makes me wonder if it's an evolutionary leftover from our days as monkeys or something like that. It's all so fascinating.

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