[HN Gopher] Mammals dream about the world they are about to expe...
       ___________________________________________________________________
        
       Mammals dream about the world they are about to experience before
       they are born
        
       Author : birriel
       Score  : 549 points
       Date   : 2021-07-26 23:28 UTC (23 hours ago)
        
 (HTM) web link (news.yale.edu)
 (TXT) w3m dump (news.yale.edu)
        
       | g3e0 wrote:
       | Reminds me of the theory that dreaming (and music) evolved to
       | "practice" hypothetical situations and emotions before they
       | happen -
       | https://whatismusic.info/blog/AUnifiedTheoryOfMusicAndDreami...
       | 
       | It's easy for me to believe that this could have initially
       | evolved to give babies slightly more preparation for the outside
       | world (and therefore a slightly higher chance of survival), and
       | that we just happen to retain the ability throughout adulthood.
        
       | dukeofdoom wrote:
       | Makes sense. Baby wildebeests has to learn to walk in minutes
       | after birth. Hungry Lions are literally waiting for their lunch
       | to be born.
        
       | l33tman wrote:
       | 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.
        
         | andai wrote:
         | The video of retinal activity [0] looks quite similar to what I
         | often see when I am falling asleep.
         | 
         | [0]: https://m.youtube.com/watch?v=qarq_UPAS1M
        
           | momirlan wrote:
           | You a ?
        
       | _pmf_ wrote:
       | "Science"
        
       | imbnwa wrote:
       | 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
        
         | noisy_boy wrote:
         | At a more "pop" level, Avatar fans with a told-you-it-is-
         | totally-possible expression.
        
       | malkia wrote:
       | That's nature's loading screen! Awesome discovery....
        
       | Geee wrote:
       | 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.
        
         | chromanoid wrote:
         | Epigenetics are one way.
         | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6127768/
        
         | UnFleshedOne wrote:
         | Parent organisms do influence the way their children develop,
         | at what extent is a different question (I understand it is
         | fractal spaghetti all the way down).
         | 
         | It seems planaria worms can do something like that [0].
         | 
         | [0] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5051648/
        
         | yellowapple wrote:
         | 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?
        
       | axiom92 wrote:
       | Similar:
       | https://www.cell.com/patterns/fulltext/S2666-3899(21)00064-7
       | 
       | Dreams help the brain in generalizing the world. From the
       | article:
       | 
       | "That is, dreams are a biological mechanism for increasing
       | generalizability via the creation of corrupted sensory inputs
       | from stochastic activity across the hierarchy of neural
       | structures."
        
       | shannifin wrote:
       | > 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 dreaming.
        
         | system2 wrote:
         | People do not read without click-bait anymore.
        
       | [deleted]
        
       | nabla9 wrote:
       | "Retinal waves prime visual motion detection by simulating future
       | optic flow", Science 23 Jul 2021: Vol. 373, Issue 6553, eabd0830
       | 
       | DOI: 10.1126/science.abd0830
       | 
       | https://science.sciencemag.org/content/373/6553/eabd0830
        
       | snack-boye wrote:
       | Imagine if this is the dream, as we get older and stuff seems to
       | make less sense is actually getting closer to birth.
        
         | momirlan wrote:
         | That's dementia
        
       | joshxyz wrote:
       | What if this life we're living is one of those dreams?
        
       | xyzzy21 wrote:
       | So mammals are NOT Tabula Rasa at all.
       | 
       | Some people today need to learn this.
        
       | lupire wrote:
       | Unit-testing the software before deployment.
        
         | darepublic wrote:
         | Yes and just like software it doesn't matter the test results
         | were still going live
        
           | vmception wrote:
           | To the host it can matter
        
             | guerrilla wrote:
             | I think you missed the point: they're going to be born and
             | have to deal with reality in any case. There would be no
             | possible consequence of a failed unit test.
        
               | vmception wrote:
               | Not if the host aborts
        
               | guerrilla wrote:
               | The woman has no idea if the baby is passing "unit tests"
               | or not, and so no abortion can depend on hypothetical
               | "unit tests." Quit with this made-up nonsense.
        
           | taneq wrote:
           | That's way less of a foregone conclusion than you seem to
           | think.
        
       | fungiblecog wrote:
       | I'm sure there is brain activity that prepares the baby for
       | birth, but calling it a "dream" is just clickbait
        
         | echelon wrote:
         | The headline is kind of beautiful, even if wrong. In a
         | /r/BrandNewSentence kind of way, but also subtle commentary
         | about cognition and our place in the consciousness landscape.
         | 
         | "Mammals dream about the world they are about to experience
         | before they are born"
         | 
         | Wow, those are some evocative feels in those words.
         | 
         | I immediately thought about Google's "DeepDream" and how
         | reversed back propagation gives us a projection of the network.
         | Growing brains similarly fire before they're trained on real
         | world perceptual inputs. Maybe these have shapes that evolved
         | to be world-like and give babies an advantage in the fitness
         | landscape.
         | 
         | My next thought: what if what we're collectively doing now --
         | all of our neural connectomes growing, dying, forming new
         | connections, evolving understandings. Society, basically -- is
         | the same shape of an AGI before birth? Maybe alien worlds tend
         | towards this path too. A bad analogy, sure, but maybe it's the
         | shape of the universe's consciousness being bootstrapped,
         | before it awakens. Not getting into metaphysical garbage --
         | just thinking about what's to come.
        
         | dogorman wrote:
         | 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."
        
           | antattack wrote:
           | Are you thinking about zygote rather than fetus perhaps?
        
           | taneq wrote:
           | I find it highly implausible that many people believe fetusus
           | are "not alive". You might be referring to the widely held
           | position that an early-term fetus isn't sufficiently
           | developed to be considered a full-fledged human, and that any
           | rights it might have don't outweigh those of the mother who
           | is carrying it?
        
             | dogorman wrote:
             | 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 people tell themselves to feel better about
             | their positions. Incidentally, I eat meat and I am pro-
             | choice.
        
               | stevenhuang wrote:
               | 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_.
        
               | dogorman wrote:
               | 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.
        
               | cma wrote:
               | 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.
        
               | dogorman wrote:
               | I suppose you'll also claim you've never met a
               | "vegetarian" who thinks "fish don't count."
        
           | mensetmanusman wrote:
           | They are all a stage of human life. I love the fact that they
           | start learning languages before exiting the womb... Life is
           | awesome!
        
         | xkeysc0re wrote:
         | The researchers call it "dream-like" and it is, in the sense
         | that, like a dream, the neurons are stimulated and activated as
         | though sensory input was occurring despite there being no
         | actual stimuli.
        
           | pvaldes wrote:
           | Foetus can have, and will have, direct experience of the
           | world before birth. In the last months of pregnancy they
           | definitely can hear what is happening outside. Will also
           | react to strong noises or gentle pressure.
           | 
           | Seeing differences at daylight or obscurity while in the womb
           | does not seem impossible. Anybody that has closed the fist
           | over a strong flashlight knows that the flesh is not totally
           | opaque.
           | 
           | Is this dreaming? Maybe, maybe not. Other explanations are
           | possible.
        
           | deburo wrote:
           | Huh, how weird. How are those stimulis generated? Through the
           | mother's eyes or brain activity?
        
             | [deleted]
        
             | jobigoud wrote:
             | "Dream-like" implies they are genetated directly in the
             | fetus brain without external stimuli.
        
             | throwamon wrote:
             | Nitpick: _stimuli_ is already the plural of _stimulus_.
        
       | imvetri wrote:
       | hmm. when the brain is floating in the stomach, it already had
       | built how the world would be.
       | 
       | Initial sense - Floating, so floated and floater exists.
       | something exist, let me figure it out. oh sometimes I sense
       | vibration, some are slow and repetitive, some are musical, oh
       | then learns about vibration and source of vibration. then
       | predicts what could be the source of vibration.
        
       | Amin699 wrote:
       | Mice, of course, differ from humans in their ability to quickly
       | navigate their environment soon after birth. However, human
       | babies are also able to immediately detect objects and identify
       | motion, such as a finger moving across their field of vision,
       | suggesting that their visual system was also primed before birth.
        
       | archibaldJ wrote:
       | Once upon a time, I woke up from a dream and was greeted by
       | friendly beings. They looked at me in wonder, and were surprised
       | I'm awake. The lights in the room were very cozy. Soon I went
       | back to sleep, and there I was, veritably back in this world
       | again. Now I do not know whether I had taken LSD and visited a
       | different world, or I had temporarily woken up from this dream,
       | and now making sense of the waking up as "a LSD experience".
        
         | __ryan__ wrote:
         | Alternatively, you were dreaming the whole time. I have _many_
         | dreams where I "woke up". I'm totally convinced it's real in
         | the dream-- even though I also have telekinesis and can fly.
        
           | dorkwood wrote:
           | I've had dreams where I'm lying in my bed, trying to fall
           | asleep. I wouldn't have known I was even dreaming if I didn't
           | stop to check.
           | 
           | For those wondering how to check if you're dreaming: pinch
           | your nose closed with your fingers. If you can inhale through
           | closed nostrils, you're dreaming.
        
       | euske wrote:
       | 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?
        
         | Davidzheng wrote:
         | 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.
        
         | fossuser wrote:
         | I don't think brains are pre-wired to recognize 3D objects.
         | 
         | There was an example case of a blind man with cataracts getting
         | it fixed at around 50 years old. People were curious if he
         | would be able to know if a sphere was round just by looking at
         | it without touching it.
         | 
         | IIRC - not only could he _not_ do that, but he couldn 't
         | visually interpret shadows (saw them as black splotches -
         | didn't recognize depth), and was confused why objects got
         | smaller as they were moving away.
         | 
         | I think the human visual system trains on a lot of visual input
         | data, but it typically happens at the baby stage where you
         | can't really interact.
        
           | echelon wrote:
           | Fascinating anecdote, and I'd love to see the report on this.
           | I wonder what else they learned from such an interesting case
           | study.
           | 
           | But I doubt it's 100% "no pre-wiring". What about gravity and
           | musculature? Surely brains must know or train on these in
           | some way before birth.
           | 
           | And what about fight or flight reflexes and presupposing
           | monsters in the shadows? My understanding is that these had a
           | primitive evolutionary basis and that we came hardwired to
           | respond to certain stimuli.
        
             | lostmsu wrote:
             | What about musculature? Human babies mostly just violently
             | shake all hands and legs right after birth.
        
               | jolmg wrote:
               | Gravity is probably also learned at the same time we
               | learn how to use our muscles from how we must compensate
               | for it when moving, also from seeing how things have a
               | tendency to approach the ground unless something gets in
               | the way, and from the sound things make when they hit the
               | floor.
               | 
               | I don't think there's much opportunity to experience
               | gravity before birth in order to train it, and I can't
               | think of anything the brain would need to know about
               | gravity beyond how we experience it with our senses.
               | 
               | > And what about fight or flight reflexes and
               | presupposing monsters in the shadows? My understanding is
               | that these had a primitive evolutionary basis and that we
               | came hardwired to respond to certain stimuli.
               | 
               | Maybe pre-wired behaviors can depend on non-pre-wired
               | stimuli, like a function that's conditioned on an
               | undefined function and evaluates to false on exception.
        
             | fossuser wrote:
             | Yeah - I just meant specifically 3D visual modeling. I
             | think some fears are known to be innate among apes - fear
             | of the dark, snakes, and falling. Also paying attention to
             | faces?
             | 
             | The cataracts thing was an article I saw on HN a few years
             | ago, but don't remember the title.
        
               | jolmg wrote:
               | > don't remember the title.
               | 
               | Found this:
               | 
               | https://news.ycombinator.com/item?id=17687533
               | 
               | which leads to:
               | 
               | https://www.newyorker.com/tech/elements/people-cured-
               | blindne...
               | 
               | which leads to:
               | 
               | https://www.newyorker.com/magazine/1993/05/10/to-see-and-
               | not...
               | 
               | > TO SEE AND NOT SEE By Oliver Sacks May 2, 1993
               | 
               | > A NEUROLOGIST'S NOTEBOOK about Virgil (pseud.), who
               | lost his eyesight as a child, and regained it at age 50.
               | Tells how he could not adjust to the sighted world, and
               | eventually had to be hospitalized.
               | 
               | Unfortunately, it needs a New Yorker account to view.
        
               | fossuser wrote:
               | Yep - that looks like the stuff I was remembering, nice
               | find.
        
       | gojomo wrote:
       | Abre los ojos.
        
         | Infernal wrote:
         | One of my favorite movies.
        
       | khr wrote:
       | This article didn't link to the research article directly. Here
       | it is for those interested:
       | 
       | https://science.sciencemag.org/content/373/6553/eabd0830/
        
       | gradschoolfail wrote:
       | TIL sheep dream about nonelectric androids
        
       | mindfulplay wrote:
       | 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.
        
         | smegger001 wrote:
         | complex emergent behaviors from simple rule systems is quiet
         | common.
         | 
         | conways game of life is derived from 4 simple rules yet shows
         | complex behavior including the ability to operate a universal
         | turring machine.
         | 
         | a few hundred megs of instructions seems quiet reasonably able
         | to generate a highly complex system
        
           | anthk wrote:
           | You can play Tetris on GNU sed. You can play Zork on a
           | PostScript interpreter by simulating the ZMachine on PS.
        
         | yreg wrote:
         | The dreaming doesn't simulate a complex world. As I understand
         | it, it might be something like a simple blob moving around in
         | 2D space.
        
         | l33tman wrote:
         | It's just expanding circular waves of activity on the retina.
         | Don't read too much into the articles clickbait headline :)
        
       | [deleted]
        
       | yellow_lead wrote:
       | The full title is pretty funny.
       | 
       | > Eyes wide shut: How newborn mammals dream the world they're
       | entering
       | 
       | Reference to the Kubrick film I assume.
        
       | gojomo wrote:
       | 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 inference
       | without compromising accuracy. However, contemporary experience
       | is that the sparse architectures produced by pruning are
       | difficult to train from the start, which would similarly improve
       | training performance._
       | 
       |  _We find that a standard pruning technique naturally uncovers
       | subnetworks whose initializations made them capable of training
       | effectively. Based on these results, we articulate the "lottery
       | ticket hypothesis:" dense, randomly-initialized, feed-forward
       | networks contain subnetworks ("winning tickets") that - when
       | trained in isolation - reach test accuracy comparable to the
       | original network in a similar number of iterations. The winning
       | tickets we find have won the initialization lottery: their
       | connections have initial weights that make training particularly
       | effective._
       | 
       |  _We present an algorithm to identify winning tickets and a
       | series of experiments that support the lottery ticket hypothesis
       | and the importance of these fortuitous initializations. We
       | consistently find winning tickets that are less than 10-20% of
       | the size of several fully-connected and convolutional feed-
       | forward architectures for MNIST and CIFAR10. Above this size, the
       | winning tickets that we find learn faster than the original
       | network and reach higher test accuracy._
       | 
       | Are these innate patterns of activity priming mammalian brains in
       | a similar way?
        
         | voldacar wrote:
         | "Neural networks" aren't very similar to brains, so I would
         | doubt it
        
         | kbenson wrote:
         | So, that sounds like a good reason to iterate over a bunch of
         | random initializations and train them up to find those awesome
         | resulting networks that are smaller but have the same accuracy
         | (if I'm understanding that correctly and it's actually possible
         | to isolate or take advantage of those subnetworks for a final
         | smaller size).
         | 
         | Or... has anyone tries training a network for determining the
         | initialization state of another network? And now I'm wondering
         | if those good starting initialization values only work well for
         | a specific task or if they seem to span all or a subset of
         | tasks, and maybe there's some inherent quality in how the
         | values relate that we can tease out...
        
         | teruakohatu wrote:
         | > 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 mature due to birth canal constraints, which
         | is constrained by pelvis size which is constrained by the need
         | to walk upright.
         | 
         | I have wondered about how true this is. Maybe our brains are
         | just so much more powerful, or capable of much deeper
         | understanding, that we require a much lower initial learning
         | rate.
         | 
         | The lottery ticket could explain why some children learn to
         | walk at 6 months, while others are closer to 24 months, with no
         | different in intelligence or motor skills in later life.
         | 
         | Edit: As some people below have correctly pointed out, human
         | babies could not walk within an hour for physiological reasons,
         | but nor do they exhibit the basic motor skills, spatial
         | reasoning or image processing required for walking. Many human
         | babies even struggle to feed for the first 24-48 hours or
         | longer.
         | 
         | Meanwhile baboon babies can hold onto their mother from birth
         | while the mother climbs trees.
        
           | jvanderbot wrote:
           | > 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.
        
           | otabdeveloper4 wrote:
           | > I have wondered about how true this is.
           | 
           | It isn't. Human babies prioritize differently. We learn to
           | understand language and to communicate before we learn to
           | walk.
           | 
           | (In fact, for many babies learning to walk is a conscious
           | process. We learn to learn before we learn to walk.)
        
           | soheil wrote:
           | > 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?
           | 
           | Probably neither. How does the human baby "learn" to breath
           | almost immediately after birth? I suspect the answer here is
           | also the same.
        
           | jacinda wrote:
           | > 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 2.0-2.5x basal metabolic rate (BMR).
           | 
           | > By 9 mo, metabolic demands of the fetus threaten to push
           | maternal energy requirements beyond 2.1x 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.
        
             | watwut wrote:
             | > constraining factor is not pelvis size
             | 
             | I kind of doubt that, because if baby is after term, the
             | risk is supposed to be childbirth itself being too
             | dangerous. And they induce birth if the baby is too big
             | too.
             | 
             | Large baby is considered a risk on itself.
        
               | eru wrote:
               | Yes. And for even larger babies, c-sections are common.
        
             | MoreenDichele wrote:
             | That's obvious bullshit because then any woman giving birth
             | to twins would die. Use your fucking brain please.
        
             | l33t2328 wrote:
             | > consume so much energy that we give birth just before a
             | women's metabolic limits would otherwise be overrun
             | 
             | Since babies traditionally breast feed and thus survive
             | solely on the mother's energy after birth, this explanation
             | doesn't seem to hold water.
        
               | minitoar wrote:
               | The truncated gestation is sort of taking that into
               | account, at least according to this paper
               | https://www.pnas.org/content/109/38/15212
        
               | slickrick216 wrote:
               | Breast feeding is quite hard on women and many women
               | struggle to sustain the child on the breast alone.
               | There's a history of communal feeding which adds new
               | energy into the equation and also mixed feeding once the
               | child is old enough. I would say it's probably a
               | continuation at the peak metabolic rate described in the
               | parent post.
        
               | eidelweissflow wrote:
               | Most women I know who struggled with breastfeeding were
               | due to inability to have the baby correctly latched. Once
               | the baby is latched, women shouldn't have a problem with
               | supply. Mother spends at most 500 calories extra when
               | breastfeeding which most of the time comes from the
               | weight that's gained during pregnancy. I myself was able
               | to exclusively breastfeed for 6 months after which we
               | started introducing solids.
        
             | Nition wrote:
             | > 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!
        
               | agent008t wrote:
               | Putting on 6kg in a year is not that fast, people do
               | sometimes gain weight faster than that in adulthood.
        
               | [deleted]
        
               | Nition wrote:
               | I'm going by average weight gain from normal growth. But
               | let's look at height instead then.
               | 
               | Average height at age 12: 59". At age 13: 62". 3" of
               | growth.
               | 
               | At birth: 19". At one year: 29". 11" of growth.
               | 
               | Try matching _that_ just by eating more.
               | 
               | (obviously, yes, it's easier for a small thing to grow
               | than a large thing. But it's still crazy fast. Imagine
               | being 50% taller in a year)
        
               | agent008t wrote:
               | You talked about weight gain, in absolute terms. A novice
               | powerlifter can easily put on both more absolute weight
               | and absolute strength in a year than a newborn.
        
               | shard wrote:
               | The image of a baby trying to outlift the weights that a
               | novice weightlifter is lifting is now ingrained in my
               | mind.
        
               | FartyMcFarter wrote:
               | That's not growth, just fat accumulation which is a much
               | simpler process.
        
               | agent008t wrote:
               | And a child puts on 100% bone and muscle?
        
               | FartyMcFarter wrote:
               | No, but I'm not sure what point you're trying to make?
        
               | agent008t wrote:
               | I was just pointing out that a baby does not gain weight
               | faster than it ever will again in its life, in absolute
               | terms. That's all. Not sure why I got the downvotes and
               | no-true-scotsman arguments in return.
        
               | tk75x wrote:
               | Plus fat and some water, yes. And furthermore, to go from
               | a 10 pound baby to a 100 pound adult, I will make the
               | claim that a baby has to gain 900% body mass.
        
               | Naracion wrote:
               | How are you defining growth? Are you defining it by
               | volume? Ie assuming the body mass density remains the
               | same, how much does the weight increase (which means the
               | body is volumetrically growing)?
               | 
               | If not--I am very lightweight right now, and I'm trying
               | to put on body mass by eating more and exercising. While
               | my volume will increase, my main growth is in density. My
               | growth is not in fat, but actual muscle mass. Is this
               | growth? If so, I have gone from 125lb to 140lb in ~2
               | months, which in absolute terms is obviously more than
               | the baby (my goal is 160lb by the end of the year).
               | 
               | A few years ago, I went from ~130lb to 165 lb in three
               | months--blame the free food at FAANG cafes during an
               | internship. But this might be closer to what you were
               | saying earlier--putting on fat.
               | 
               | Edit. I guess in the original statement saying that a
               | person will never gain weight at this rate again there
               | should be the explicit assumption that we're talking
               | about natural growth, not growth due to external factors
               | (ie more eating--intentional or not). In that case, that
               | statement would be true.
        
               | agent008t wrote:
               | I wouldn't say that growth through eating is unnatural
               | though.
        
               | Naracion wrote:
               | I guess what I might have implied by "natural" is growth
               | from growing older as opposed to growth from nutrition.
               | 
               | But in that sense, of course a baby will have more growth
               | than an adult--isn't it reverse exponential?
        
               | ljf wrote:
               | But putting on 100% or even 200% of weight in a year is
               | not normal or even possible for most adults without
               | crippling their health. All babies do this.
        
               | pedrosorio wrote:
               | I believe the GP was contesting the "In absolute terms!"
               | part of the comment.
        
               | techrat wrote:
               | Diminishing returns as the numbers of scale increase.
               | 
               | The growth might seem impressive when you do percentages
               | of a very small number, but it's still a very small
               | number overall.
        
               | Nition wrote:
               | It's not though, that's my point. Even in absolute terms,
               | weight gain from growth in the first year is _still_ more
               | than any other time in the average person 's life.
        
             | eru wrote:
             | > 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.
             | 
             | This seems weird. Fully breastfed babies require even more
             | calories from the mother. (They are bigger than unborn
             | babies, and they lose more heat.)
        
               | mandelken wrote:
               | Perhaps it's more than just calories or energy intake,
               | but as well doing the breathing, immuno responses,
               | digesting, filtering blood etc. for both mother and baby?
        
               | eru wrote:
               | Maybe. But now we are just speculating.
        
               | TheGeminon wrote:
               | > 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.
               | 
               | Growth rate slows after birth, so that would account for
               | some of that. Mother's also would not need to carry
               | around the weight of the baby, and would be more able to
               | provide for the child.
        
               | a0-prw wrote:
               | Women in Africa (in traditional societies), carried their
               | babies on their backs while they worked the fields,
               | carried water, etc.
        
           | akomtu wrote:
           | I guess it's firmware of some kind. Newborns already know how
           | to breathe, how to control the heart rate and tons of other
           | low level things. Legs movement is a small feature in
           | comparison.
        
             | pbhjpbhj wrote:
             | Newborns don't even know the legs belong to them.
        
           | rowanG077 wrote:
           | Interesting. Could this also partly explain child geniuses?
           | In general they are worlds ahead early in life. But they
           | aren't significantly better then the non child genius peers
           | later in life.
        
           | taneq wrote:
           | > 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 human pelvis.
        
             | phire wrote:
             | Babies can't even roll-over until 4-6 months
        
               | amock wrote:
               | 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.
        
               | nemo44x wrote:
               | 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.
        
             | briefcomment wrote:
             | This person's baby walked at 8 months [1]
             | 
             | [1] https://www.scarymommy.com/complete-shock-early-
             | walking-baby...
        
               | taneq wrote:
               | 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.
        
               | pbhjpbhj wrote:
               | Earliest I've seen was 9/10 months, that kid looked so
               | strange to me, they could barely hold their head up as
               | they tottered around like a drunk. I wonder if the
               | parents promoted early walking?
        
               | octopoc wrote:
               | People do that successfully, the problem is that if
               | babies skip the crawling phase then it may cause learning
               | disabilities among other things. Which is fascinating in
               | the context of this conversation. The order in which
               | things are learned can be very critical!
        
               | pbhjpbhj wrote:
               | Yes, successful crawlers might walk later, kids that
               | learn to bum-shuffle (propel forwards whilst sitting on
               | their bottoms) might not crawl much.
               | 
               | Our eldest wasn't interested in crawling really and went
               | _almost_ straight to walking but not until about 14
               | months IIRC (it was  > 10 years back).
               | 
               | We did baby sign (a sort of simplified BSL; would
               | recommend) and some people suggested it would retard
               | speech - same child modified a sign before 12 months and
               | so could tell us he needed a poo/wee and we'd sit him on
               | the potty to do it all before he was able to talk - saved
               | me changing a lot of stinky nappies! Longitudinally, our
               | kids used baby sign and did/are doing well at school and
               | have all been ahead with language skills (but that's not
               | accounting for confounding variables).
               | 
               | It's curious to see infant developmental stages becoming
               | more and more to be compared to AI/robot development.
        
             | pankajdoharey wrote:
             | Intel is an Old baby who walks with crutches. Intel
             | delivered the 10nm Processor just 2 months back after a
             | decade of failure. Their 7nm is still broken and so is
             | there 5 and 3nm in research. And they hope to catch up to
             | the competition by 2025 is a funny joke. Intel isnt a
             | reliable delivery partner which is why Apple moved away to
             | its own processors.
        
           | beerandt wrote:
           | >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.
        
           | raverbashing wrote:
           | > 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?
           | 
           | Or maybe having 4 legs (as a foal) gives more natural balance
           | than a human or maybe even a cat or dog.
           | 
           | In the same way technically you only need one leg to walk
           | (hop) around but that's much more difficult than having two.
        
             | KronisLV wrote:
             | That's a fair point!
             | 
             | However, another commenter brought up the fact that human
             | muscles are somewhat underdeveloped after birth. It might
             | make sense that having 4 legs is easier both in regards to
             | balance, as well as because the load per leg decreases to
             | make standing on them easier.
             | 
             | That is probably not the only reason, but probably a
             | contributing factor.
        
           | chrisseaton wrote:
           | > 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.
        
             | GreeningRun wrote:
             | If I follow your reasoning on the leg muscles, how to deal
             | with the grasping reflex? That's all the weight on just
             | some arm muscles...
        
             | narag wrote:
             | _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.
        
             | outworlder wrote:
             | True. But the movements on all limbs are quite
             | uncoordinated at first. It's also not restricted to muscle
             | strength.
        
             | emmelaich wrote:
             | 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.
        
               | throw_nbvc1234 wrote:
               | Except that children can walk with assistance (and crawl)
               | before they're strong enough to walk on their own.
        
               | underwater wrote:
               | 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.
        
               | adamauckland wrote:
               | 'Walking by one, talking by two'
        
               | [deleted]
        
               | chrisseaton wrote:
               | But if you hold a child up before their legs are strong
               | enough they will walk.
        
               | freemint wrote:
               | 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.
        
             | danielheath wrote:
             | 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.
        
               | gambiting wrote:
               | I have a 10 week old baby right now, he can absolutely
               | stand on his legs if you hold him steady - but yeah, he
               | has absolutely zero clue what to do from there :P Also
               | he's got a kick that you really need to watch out for,
               | strong little dude.
        
               | jacobolus wrote:
               | The balance can also be trained relatively quickly, but
               | newborns typically get very little practice.
               | 
               | If you start occasionally holding your baby up by the
               | thighs when they are 4-5 months old (their back/abdomen
               | muscles at that point are typically plenty strong), after
               | about a month they will have the balance to hold their
               | torso upright when sitting on an adult's shoulders, for
               | at least a while. By age 8-9 months they will be very
               | stable and good at balancing for long stretches of time.
               | (I recommend any new parent try this, not only for the
               | baby's sake but because carrying a baby on shoulders is
               | dramatically less tiring for an adult than carrying a
               | baby in arms, and less hassle than a stroller or baby
               | carrier.)
               | 
               | People generally hold their babies from the top (e.g.
               | with hands in armpits), in a way that they are passively
               | stable. If you want to train someone's balance, you want
               | to force them to actively stabilize themselves from a
               | default-unstable position at least a bit every day.
               | Babies have very short torsos and small heads compared to
               | older kids, with the effect that their torsos have a much
               | smaller moment of inertia about the waist: it takes
               | several times more muscle strength for a 3-year-old to
               | lift their torso up.
        
               | mortehu wrote:
               | Based on my experience with our first child, these might
               | be placebo exercises, and the babies might have met those
               | goals on their own. Assuming you haven't done a
               | randomized trial.
        
               | jacobolus wrote:
               | Based on which experience? My experience with now 2 young
               | kids and their playground buddies is that whichever
               | skills they regularly practice improve very dramatically
               | compared to skills they don't practice. The differences
               | are not at all subtle.
               | 
               | If you get a few 3-year-olds and e.g. get one to practice
               | kicking a ball for 10 minutes per day, another to
               | practice riding a 2-wheeled scooter, another to practice
               | hanging from monkey bars, and another to practice
               | swimming, after a few months there will be a wide gulf
               | between their abilities at those skills.
        
               | davchana wrote:
               | > If you start occasionally holding your baby up by the
               | thighs when they are 4-5 months...
               | 
               | Do you mean baby sits on my shoulder with his legs around
               | my neck, I am holding on to his thighs, and he can hold
               | on to my head with arms? We both face forward in same
               | direction.
        
               | jacobolus wrote:
               | No, I mean you hold your baby by the thighs, facing you,
               | and let him balance his torso upright by flexing his
               | abdominal/back muscles. At first, the baby will not have
               | the coordination to stay upright very well, but actively
               | stabilizing himself will train that balance. Because you
               | are holding the thighs, the baby only has to stabilize
               | one joint (the waist).
               | 
               | Then after a month or two of practice (a few minutes per
               | day, nothing too serious here) you put your baby on your
               | shoulders, holding his ankles, and he will be able to
               | hold his torso up with his abdominal muscles for at least
               | a few minutes at a time. Practice this for a few more
               | weeks and you will be able to walk around town with the
               | baby on your shoulders.
        
               | davchana wrote:
               | Oh I get that. Kind of what my parents did that always
               | pick up baby from waist(if he is sitting down) & holding
               | him only at thighs/waist. I see some people pick up by
               | from their underarms.
        
           | gojomo wrote:
           | Maybe given the length & complexity of a full human life, a
           | bunch of brain factors actually work to _slow specialization
           | down_ to prevent early overfitting.
        
           | jovdg wrote:
           | > Edit: As some people below have correctly pointed out,
           | human babies could not walk within an hour for physiological
           | reasons, but nor do they exhibit the basic motor skills,
           | spatial reasoning or image processing required for walking.
           | Many human babies even struggle to feed for the first 24-48
           | hours or longer.
           | 
           | https://www.stanfordchildrens.org/en/topic/default?id=newbor.
           | ..
           | 
           | > Stepping reflex > > This reflex is also called the walking
           | or dance reflex because a baby appears to take steps or dance
           | when held upright with his or her feet touching a solid
           | surface. This reflex lasts about 2 months.
           | 
           | Maybe not enough to qualify as "exhibit the basic motor
           | skills"
        
           | retrac wrote:
           | > 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 seconds.
           | 
           | A robot could be built that learns how to adapt to something
           | like a limb being lost or added or half its weight shifted to
           | the other end. It could probably learn an approximate optimal
           | to move under those conditions in just seconds, as well.
           | Though, I suspect that foal might actually be nearly as
           | adaptable. Adult horses, or humans... not so much. We have
           | many overlapping models of how to move, probably. I would
           | take only seconds to adapt to half my weight being added on
           | my shoulders, in the same ballpark as our best robotic
           | systems. But if my left leg grew four inches it would take me
           | a lot longer than the robot to learn and internalize the best
           | way to move again. I could barely keep up with that when it
           | was just a few inches a year when I was a kid.
        
             | teruakohatu wrote:
             | > 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.
        
               | smegger001 wrote:
               | 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
        
               | retrac wrote:
               | We do have self-driving cars we just don't have any we
               | think are good enough, well-tested, and adaptable to
               | mixed-use driving and our various regulatory and safety
               | and cultural needs. You can't get regulatory approval for
               | a car that learns to drive by guided trial and error in
               | the wild -- which is the most direct way of training such
               | a thing. Feedback on what you shouldn't drive over also
               | isn't as immediate and unambiguous, compared to whether
               | gravity will topple it over.
        
             | lelanthran wrote:
             | > 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 seconds.
             | 
             | Firstly, the drone software is not re-learning anything;
             | when a baby walks unaided for the first time and you place
             | a rattle in their hands, do you really refer to that as
             | "re-learning walking"?
             | 
             | Secondly, forget about computational requirements and just
             | look at how many iterations have to be run to reach
             | success; mammals (and humans specifically) can "learn" to
             | recognise an entire class of something just from one or two
             | images of that something. Learning something else doesn't
             | "forget" the old thing. A NN trained to recognise faces in
             | images can't, to me knowledge, be trained to _also_ balance
             | a bi-pedal robot, or ride a bicycle.
             | 
             | IOW, what I see currently is that NNs are very one-
             | dimensional - the net that becomes optimised for one task
             | becomes unoptimised for that task if you subsequently add
             | new tasks.
        
           | 3pt14159 wrote:
           | > that we require a much lower initial learning rate.
           | 
           | The way I understand it is that is not so much required as
           | not selected for. We could certainly be able to walk at one
           | day old if evolutionary pressure made it necessary, but it
           | prioritized other aspects in our cognitive development to
           | survive so we don't. It's not as if we say "oh, horses can
           | walk early and therefore are incapable of rational thought"
           | we evaluate them on their own merits.
        
           | hanoz wrote:
           | _> Most human babies take 9-18 months to walk, and this is
           | commonly attributed to the fact that human babies have
           | immature brains..._
           | 
           | Isn't it just a matter of priorities? Many birds spend a
           | similar proportion of their life unable to fly, but they're
           | safe in a nest. If you're a foal on the savanna, you need to
           | get up.
        
             | a0-prw wrote:
             | Yes, I agree. Horses are exclusively prey animals in a
             | natural setting. A newborn human would have had it's armed
             | "pack" to protect it from predators.
        
           | afavour wrote:
           | 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.
        
             | tigershark wrote:
             | They can even swim safely underwater thanks to a reflex.
        
             | the_af wrote:
             | 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.
        
               | patentatt wrote:
               | And it's usually an incredibly strong grip! Seems like it
               | could definitely be used to grab onto a monkey mother's
               | back, never thought about that!
        
             | l33tman wrote:
             | 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.
        
         | teawrecks wrote:
         | In the context of real life we draw a distinction between thus
         | neonatal dreamlike state and post birth "reality". But in the
         | context of a neural net, I don't think such a distinction is
         | necessary. They both sound like they're training the network.
         | Still interesting to consider the parallels though.
        
         | emtel wrote:
         | It's not just mammals. I've always been astounded that spiders
         | know how to spin webs. Their mothers don't teach them how!
        
           | gota wrote:
           | Or this, which is mind-blowing:
           | 
           | https://www.smithsonianmag.com/smart-news/dragonfly-
           | undertak...
           | 
           | Insects that have large migration patterns - all of the
           | individuals die before coming back to the initial spot; only
           | their descendants continue the cycle. How?!
        
             | chromanoid wrote:
             | Maybe epigenetics? I mean blank slate theory is off the
             | table anyway...
             | 
             | In addition think about how bees can tell harvest locations
             | to each other by dancing:
             | https://en.wikipedia.org/wiki/Waggle_dance This dance is
             | probably also something those bees know before being born.
        
         | stared wrote:
         | I think it is less relevant to Winning Ticket Hypothesis (in my
         | opinion, the most important paper on deep learning theory in
         | the last 5 years), but about architectures that work to some
         | extend with random weights.
         | 
         | See "Weight Agnostic Neural Networks"
         | (https://weightagnostic.github.io/):
         | 
         | > Inspired by precocial species in biology, we set out to
         | search for neural net architectures that can already (sort of)
         | perform various tasks even when they use random weight values.
        
         | dexen wrote:
         | Reminds me the old anecdote,                 In the days when
         | Sussman was a novice Minsky once came to him as he sat
         | hacking at the PDP-6.  "What are you doing?", asked Minsky.  "I
         | am       training a randomly wired neural net to play Tic-Tac-
         | Toe."  "Why is the       net wired randomly?", asked Minsky.
         | "I do not want it to have any       preconceptions of how to
         | play." Minsky shut his eyes.  "Why do you       close your
         | eyes?", Sussman asked his teacher.  "So the room will be
         | empty."  At that moment, Sussman was enlightened.
        
         | gota wrote:
         | I guess I can see some parallel the way you describe it, but it
         | is not that tight of an analogy IMO. Correct me if I'm wrong
         | but the Lottery Ticket Hypothesis mainly means that, for many
         | of our tasks, we start with needlessly huge networks, and thus
         | a good portion of the learning process is just the network
         | learning to "cope with the noise" from the extraneous
         | connections
         | 
         | Hence why the lottery ticket network (being a smaller version
         | of the same _initial_ network) can achieve similar accuracy
         | (but not  'better') in much shorter time - because you took
         | away all the confounding stuff. That kind of 'counterfactual'
         | doesn't really translate to a biological domain, right?
         | 
         | Also - the baby brain is not really a 'pruned', smaller version
         | of the adult brain, right? Neither is the fetus brain compared
         | to the baby brain (which is more to the point of the article).
         | So the analogy breaks down there too
         | 
         | I guess what the article describes is a bit like "pre-training"
         | a full network with 'synthetic' experiences that quickly tune
         | it for later. In that sense, I think its like these "dreams"
         | are a 'distilled dataset' [1]. The question then is: how is
         | this dataset being passed on from mother/father to child?
         | 
         | [1] https://arxiv.org/abs/1811.10959
         | 
         | Abstract:
         | 
         | > _Model distillation aims to distill the knowledge of a
         | complex model into a simpler one. In this paper, we consider an
         | alternative formulation called dataset distillation: we keep
         | the model fixed and instead attempt to distill the knowledge
         | from a large training dataset into a small one. The idea is to
         | synthesize a small number of data points that do not need to
         | come from the correct data distribution, but will, when given
         | to the learning algorithm as training data, approximate the
         | model trained on the original data. For example, we show that
         | it is possible to compress 60,000 MNIST training images into
         | just 10 synthetic distilled images (one per class) and achieve
         | close to original performance with only a few gradient descent
         | steps, given a fixed network initialization. We evaluate our
         | method in various initialization settings and with different
         | learning objectives. Experiments on multiple datasets show the
         | advantage of our approach compared to alternative methods._
        
           | UnFleshedOne wrote:
           | > Also - the baby brain is not really a 'pruned', smaller
           | version of the adult brain, right
           | 
           | I think it is the other way around -- adult brain is a
           | physically pruned version of baby brain. We start with lots
           | of connections from everywhere to wherever and then lose a
           | lot of them as we learn, while strengthening useful ones.
        
         | optimalsolver wrote:
         | How hard would it be to find random networks that don't need to
         | be trained at all?
        
           | AnIdiotOnTheNet wrote:
           | 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...
        
             | CaptainNegative wrote:
             | 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.
        
               | freemint wrote:
               | In the absence of dynamics and uniform random mutation,
               | yes. But Both don't hold in the universe.
        
           | belgian_guy wrote:
           | Surprisingly, it's quite doable in practice. See e.g.
           | https://arxiv.org/abs/1911.13299.
        
       | sjg007 wrote:
       | 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?
        
         | rudyfink wrote:
         | 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 number of forward and backward
         | citations if you are interested. Perhaps someone with far more
         | than my vague recollection of a talk will step in though!
        
           | hypertele-Xii wrote:
           | 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.
        
       | jherm7 wrote:
       | Poor giraffes dreaming they can walk right when they're born only
       | to come tumbling down. Ah, gravity, thou art a heartless bitch.
        
       | KhoomeiK wrote:
       | Reminds me of recent Reinforcement Learning work on learning from
       | internal world model "dreams".
       | 
       | https://worldmodels.github.io/
        
       | z3t4 wrote:
       | Likely the fetus get spatial sense at some stage before birth...
        
       | Tycho wrote:
       | Maybe telepathy/ESP is real, it's just that we lose it soon after
       | birth, or in early childhood, like eidetic memory. Or perhaps
       | some people retain it longer - or some animals, hence all the
       | mythical beasts.
        
         | chromanoid wrote:
         | Yeah, this is much more probable than a mechanism to replay
         | genetically/biochemically encoded activation patterns that help
         | survival after birth.
        
           | Tycho wrote:
           | Why the sarcasm?
        
             | chromanoid wrote:
             | Because it is an obviously improbable reasoning. Ever heard
             | of Occam's razor?
        
       | throwawaybchr wrote:
       | These kinds of claims are near impossible to prove with certainty
       | so it all seems very self gratifying
        
       | wombatmobile wrote:
       | > 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.
        
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