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Ask HN: Teach me something new

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Re: Ask HN: Teach me something new

#641

Post by andbberger »

kaba0 wrote: post #596
SemanticStrengh wrote: post #179

Earlier quoted context omitted.

> There have been cases studies of people with a fully ablated cerebellum, and they can still walk, just a bit unsteadily. ? I had heard the cerebellum is responsible for predicting the next token in a sentence (reminiscent of language models) but you're saying language is not impaired without a cerebellum?

The axons are just as important as the neurons. While neural networks are not good analogues of the real thing, one can imagine that no matter the neurons, without weights between them it would be utterly useless. The cerebrum is chock full of axons.

> The axons are just as important as the neurons.

what. an axon is a component of a neuron

are you referring to glia?

Re: Ask HN: Teach me something new

#642

Post by andbberger »

SemanticStrengh wrote: post #155
andbberger wrote: post #147

Earlier quoted context omitted.

this is a terrible list of 'brain facts'. they're not interesting or constructive to a larger understanding, and analogizing the cerebellum to a GPU is naive and misleading to the point of being insulting. working neuroscientist don't think about consciousness, we look at neurobiology, develop experimental techniques to allow imaging of ever larger numbers of neurons, try to understand how the brain computes. I don't…

What an absurd dismissal. > they're not interesting You have a failure of appreciation, yet those facts are potent and surprising. >constructive to a larger understanding Yes they are not, who cares? Teaching neuroscience is of course a non-goal of my comment, what an irrelevant thing to say.. >analogizing the cerebellum to a GPU is naive and misleading to the point of being insulting. Exactly, but if you had allocat…

> we lack real-time datasets and we lack accurate instruments to observe and retroengineer the while system.

wrong again. whole brain 2p imaging is routinely performed in c elegans ( and drosophila for that matter) for a number of years now. in fact whole brain ephys in c elegans is feasible, although it would be an experimental tour de force. c elegans does not have '~150-300 neurons', it has precisely 302, and the complexity therein cannot be underestimated. it wasn't a layman explanation for I am not a layman, and you are missing my point, which is that reductive facts about such staggeringly complex things are neither interesting or useful. it's the feynman magnet explanation, but grumpier

Re: Ask HN: Teach me something new

#643

Post by tsol »

mijoharas wrote: post #362
mikelevins wrote: post #28

I've described this on HN before; forgive me if you've already seen it. I have chronic migraine. It sounds worse than it is; I rarely suffer attacks anymore, and when I do, they're usually mostly harmless, as in the case I'll describe below. Contrary to popular belief, migraine is not a headache. It's something a little more like an epileptic seizure. Intense headaches are one common symptom, but there are a lot of o…

I'd recommend the book "the man who mistook his wife for a hat" by Oliver Sacks which I seem to remember digs into some phenomonon like these. There are very interesting differences between certain lesions in the left side of the brain, and in the right side. For instance there are some people that are blind, but do not believe that they are, and vice versa, which lines up with your experience.

This is a great look at just got complicated the brain is. What we experience and are conciously aware of, is only a fraction of the activity in one's brain. People that are convinced their limbs aren't their own, people that lose the comprehension of the concept of 'the left side'(ie of their body), people that are convinced they are stuck in the year 1990-- the brain works in a very specific way and damage to certain areas can derange the whole process and create unexpected effects. Often this is losing access to functionality that we think "just is"-- when in fact such functionality is the result of a complex integrated circuit in the brain.

Re: Ask HN: Teach me something new

#644

Post by leobg »

A tree that germinated before the Great Pyramid was built is still alive today: The Methuselah tree in Inyo County in eastern California. It is the oldest non-clonal organism that is still alive that we know.

Re: Ask HN: Teach me something new

#645

Post by Contexti »

euroderf wrote: post #511
DavidSJ wrote: post #291

Earlier quoted context omitted.

On this general topic, I recently learned that the words undulate and water have the same origin in Proto-Indo-European: wódr̥ (PIE) → udōr (Proto-Italic) → unda (Latin) → undulātus (Late Latin) → undulate (English) wódr̥ (PIE) → watōr (Proto-Germanic) → *watar (Proto-West Germanic) → wæter (Old English) → water (Middle English) → water (English) In fact, I'm now noticing that the t in the Proto-Germanic line corresp…

In IE languages, the words for water basically follow either "aqua" or "water". Finnish (it's Ugric, not IE) follows the latter, with "vesi" (combining form "vete-").

To be pedantic, Finnish is not Ugric. Hungarian is Ugric, Finnish is Finnic. They both are Finno-Ugric, a.k.a Uralic. Many non-linguist Finns mix up Finno-Ugric and Ugric.

The Proto-Uralic *weti "water" looks like it could come from IE *u̯ódr̥, *udén- "water", but that etymology is problematic because of irregular sound substitutions[0]:

- why would Uralic have *e when it's not present in the IE original?

- why would Uralic drop *r or *n at the end?

[0] Simon, Z. (2020). Urindogermanische Lehnwörter in den uralischen und finno-ugrischen Grundsprachen. Indogermanische Forschungen, 125(1), 239–266. https://doi.org/10.1515/if-2020-011

Re: Ask HN: Teach me something new

#646

Post by tsol »

wazoox wrote: post #554
mikelevins wrote: post #28

I've described this on HN before; forgive me if you've already seen it. I have chronic migraine. It sounds worse than it is; I rarely suffer attacks anymore, and when I do, they're usually mostly harmless, as in the case I'll describe below. Contrary to popular belief, migraine is not a headache. It's something a little more like an epileptic seizure. Intense headaches are one common symptom, but there are a lot of o…

I used to suffer from these auras from 2005 to 2015. I never had one before, and they completely disappeared since then. I don't think they were ever followed by any headache, either. A funny but related story: I was visiting Paray-le-Monial where there's a diorama about the visions of Saint Margaret-Mary ( https://en.wikipedia.org/wiki/Margaret_Mary_Alacoque ), who is at the origin of the current cult of the "Sacred…

It's amazing how her beliefs allowed her to turn migraines into sainthood. The ability to give meaning to unavoidable pain is a precious thing

Re: Ask HN: Teach me something new

#647

Post by leobg »

illwrks wrote: post #26

Almost everything around you has been designed by another person, or teams of people.

Almost everything around you has been shaped by the human hand.

I had this thought while walking down the street in a foreign country. And I remember it having quite a profound effect on me. What a marvelous thing it is, our hand!

(It even applies to many things we would call „nature“, such as woods or meadows.)

Re: Ask HN: Teach me something new

#648

Post by tsol »

ticklemyelmo wrote: post #481
idrios wrote: post #119

In drug development, a lot of the engineering goes into making sure the pharmaceutical compound -- having been developed -- actually reaches the target area of the body. If the compound is a relatively large particle that needs to get into the blood stream, a nasal spray might result in the compound being deposited at the bottom of a person's lungs without ever getting absorbed. If stomach acids break the chemical do…

When I was researching my kid's ADHD medicine I was fascinated to learn about its osmotic release delivery system ( https://en.wikipedia.org/wiki/Osmotic-controlled_release_ora... ). What looks like a simple pill is actually a tiny machine that delivers the medicine at a precisely controlled rate over a period of hours.

Time release medications in general are fascinating. There's another ADHD medicine, Vyvanse, that has a really interesting mechanism. The (dextro)amphetamine molecule is chemically binded to l-lysine-- a common amino acid. This makes it inactive, so one can't just snort it. It must be ingested, where in the digestive tract it meets protelytic enzymes that break down the bonds of amino acids. So it detaches the l-lysine molecules and then amphetamine molecules-- but only at a set rate. See, because there's only a finite amount of proteolytic enzymes in the gut this breakdown occurs at a predictable rate. It's so simple yet so complex at the same time, really is a brilliant time release mechanism

Re: Ask HN: Teach me something new

#649

Post by freemint »

ZeroGravitas wrote: post #411
tromp wrote: post #356

Earlier quoted context omitted.

The word "Yankee" originates in calling early Dutch colonists Jan-Kees, Jan and Kees being common Dutch male names.

Jan is the equivalent name as John, Ian, Ivan, Ewan, Euan, Yan, Jean, Juan, Giovanni, Hans, Shaun, Sean, Jock, many others. Amazing how many terms for 'foreigner from ' or 'random man' all resolve to variants of the same common name.

If you are wondering about Hans.

Johann -> Johannes -> Hannes -> Hans

Re: Ask HN: Teach me something new

#650

Post by is_true »

someweirdperson wrote: post #352
silisili wrote: post #63

I'm going to go a bit random...get a styptic pencil! Nobody I've met even knows what they are. I came across them years ago in the shaving section, and was blown away by their utility. They are solid pieces of some saltlike material that are super effective at stopping bleeding. We don't even have bandaids in our house anymore, the pencils are way more useful.

This is not medical advice, but... Cyanoacrylate (also known as "Super glue"). I've been using it to cover some small clean cuts. I think today there's even variants approved for such use.

I'm from Argentina and I've been "glued" a couple of times by paramedics using a glue based on cyanocrylate
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