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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

#71

Post by cma »

dogorman wrote: post #56
stevenhuang wrote: post #42

Earlier quoted context omitted.

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.

Isn't that part of rationale for roe v wade 3rd trimester rule already?

I've never heard someone say farm animals can't feel pain.

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

#73

Post by noisy_boy »

imbnwa wrote: post #16

Plato grinning ear-to-ear somewhere right now Freud also predicted this in that he postulated that hallucination was more primordial than actual sense-experience

At a more "pop" level, Avatar fans with a told-you-it-is-totally-possible expression.

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

#74

Post by beerandt »

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…

>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, which is constrained by pelvis size which is constrained by the need to walk upright.

You have this a bit backwards- yes brain size at birth is limited by pelvis size, but this means that humans are born prematurely compared to other mammals. The entire body is basically premature and underdeveloped, not just the head/brain. If anything the brain is relatively over-developed, as it's size is the constraining factor in gestation length.

If I remember correctly, 18-24 months is the estimated gestation time humans would have if not restricted by pelvis size (which ironically is itself a result of walking upright), and this fits better with the idea of being able to walk closer to birth.

There's a chapter in "Born to Run" that ties human physiology and endurance and evolution and brain development together in a way that's so elegant, it almost has to be true. It covers the steps that lead to the need for a bigger brain and walking upright as a means for persistence hunting. Highly recommended reading, especially that chapter.

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

#75

Post by the_af »

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…

Also the grasping reflex: if you place your finger in the palm of a newborn's hand, she will grasp it. It works almost without fail with any newborn baby. After a few months it completely disappears: grasping is no longer a reflex but a voluntary act, and as often as not she won't be inclined to do it.

I read that both failure to demonstrate these reflexes while newborn, as well as continued existence past a few months old, are signs that something might not be entirely right with the baby.

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

#76

Post by danielheath »

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.

I’ve seen a 2mo with the leg strength required. If you balanced them they would hold themselves up, no problem.

The balance comes much later than the strength.

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

#77

Post by Nition »

jacinda wrote: post #70
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…

> 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 wou…

> Instead, the mother delivers and the neonate’s growth rate slows relative to its fetal growth rate.

Worth noting how massive the growth rate is I think: Even after birth, the baby gains weight faster than it ever will again in its life. In absolute terms! In relative terms it's even more insane.

A 12-year-old boy going through puberty will go from 90lb to 100lb over a year, an increase of 10lb or ~10%.

The average baby boy will be born at 7.5lb and weigh 20lb at one year old, an increase of 12.5lb or ~270%. Nearly triple the size!

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

#79

Post by voldacar »

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…

"Neural networks" aren't very similar to brains, so I would doubt it

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

#80

Post by smegger001 »

teruakohatu wrote: post #59
retrac wrote: post #31

Earlier quoted context omitted.

> 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…

Because the average first time driver is primed with approximately 15 years of training data from observation of not just driving deriving a complex physics model, object detection and identification system, spacial reasoning, natural language comprehensions, theory of mind able to predict behavior of other drivers based on subtle cues, and teen drivers are still awful at it as a rule with much higher accident rate.

Trying to build a neural net or set of neural nets that can do all of those jobs is a daunting task and no one has the time to train the artificial neural network for 15 years. that's why we don't have safe self driving cares yet.

as for the horse, well 50 millions of years of evolution on constantly refined genetic algorithm is hard to beat and that was on top of the evolution of the eohippus as a starting point

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