16 comments

  • padolsey 13 hours ago
    My understanding was that strokes caused brain cell death, and that there was no coming back from that, but my neurologists would speak of 'bruised' brain cells, and that after weeks or months or even years you can see recovered function. UCLA's work here is targeting this disconnection and the lost rhythm in the surviving, distant networks. However there is, as yet, NO concievable intervention that could recover function from cell death at that center of the infarct.
    • jmalicki 9 hours ago
      This talks about connections.

      My understanding is that while brain cell death (outside of the hippocampus, at least) cannot regenerate, the connections and networks can.

      But neurons regenerating connections between each other is, afaik, been pretty mainstream for awhile. The brain can't generate new cells, but it can rewire the connections between them, is what I understand. From reading the article, it seems to only claim rewiring connections, not regenerating cells.

      There are a ton of upcoming drugs that help stimulating rewiring, for instance:

      https://www.nia.nih.gov/news/new-drug-candidate-targeting-sy...

      https://pmc.ncbi.nlm.nih.gov/articles/PMC8190578/

      https://www.medicalnewstoday.com/articles/324410

      etc.

      • adastra22 8 hours ago
        There is lots of neural regeneration in the brain at the cellular level. The science on this is changing quickly.

        But even though there are new brain cells growing, that does not mean you can reform lost structure.

      • oneshtein 7 hours ago
        Lion’s mane mushroom and extracts are used by boxers to repair their brains. But it cannot be patented.
    • asdff 11 hours ago
      There are people who are missing huge percentages of their brain from injury or other issues and lead a seemingly normal life.

      https://www.cbc.ca/radio/asithappens/as-it-happens-thursday-...

      • throwup238 10 hours ago
        The original paper did not say that a huge percentage of their brain was missing [1], that was the journalist's flourish based on their own misunderstanding.

        Tissue can be compressed, stretched, reorganized, or displaced especially to compensate for a congenital condition - the patient's brain had a lifetime to adapt to hydrocephalus, which pushed on the other brain tissue. The gray cortical shell is clearly visible in those images and their volume on a scan is not representative of neuron count or synaptic capacity.

        There are far more dramatic cases of brain damage and neuroplasticity that reorganizes major functions, but there are a lot of caveats.

        [1] https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

    • deepsun 6 hours ago
      My understanding is that brain is composed of way more neurons than required, for resiliency. So if it gets a "bruise" in some part, when even a large portion of the cells are dead -- it can still function at 100%. Like a programmer without a finger. The problem is visible only when all the cells in some part are dead.

      That's why crows, with their low brain mass are pretty clever (and why all arguments equating brain size and smartness are wrong).

      Just my layman understanding.

      • sigmoid10 6 hours ago
        Crows (and certain other bird species) have a peculiar forebrain (different in structure but similar in function/evolution to the neocortex in mammals) with neuron counts rivalling primates. So the nr of neurons still matters, but likely not across the entire brain.
        • metalman 3 hours ago
          my understanding is that extream migrators actualy consume (use as energy) parts of there own brains durring there epic flights, and other species do something similar in the winter and regrow parts of there brains every spring.
          • sigmoid10 3 hours ago
            It is true that they can shrink some organs to reduce weight and store extra fat, but the brain is not one of them. Would be pretty bad, because brain cells can't regrow like e.g. a liver can.
    • rasmus1610 5 hours ago
      it is more like that the brain learns to use other regions or neurons to do the tasks of the dead brain cells. The brain cells that are dead due to ischemia are dead and will usually be collected by microglia and after some time there are defects in the brain where the ischemia was.
    • foota 12 hours ago
      One wonders if someday we might be able to resurrect the neural network from dead cells by somehow reviving the connections between neurons. I imagine that the connections stay, but become dormant when the neuron dies.
      • asdff 11 hours ago
        There is nothing to resurrect. They get digested by the microglia.
        • foota 9 hours ago
          Ah, I didn't know that existed. TIL
        • s5300 7 hours ago
          [dead]
      • steve_taylor 12 hours ago
        Perhaps, but I think that by the time we're that far advanced, strokes will be entirely preventable.
        • OneDeuxTriSeiGo 11 hours ago
          Strokes will never be preventable. You can mitigate them but a stroke isn't really a disease. It's a symptom.

          An ischemic stroke (i.e. stroke due to a clot) caused by vascular or cardiac issues can be mitigated. A cryptogenic stroke however is idiopathic and therefore has no understood cause. These types of strokes make up 30-40% of all strokes. Unless we figure out their cause, there's no way to really prevent them.

          But then there's also hemorrhagic strokes which are an entirely separate category that has causes and mitigations more or less diametrically opposed to those for ischemic strokes.

          And of course those are just your broad painted categories and they are generally looked at as the start of a medical emergency but strokes happen all the time as a consequence of other medical emergencies.

          Even if you could perfectly prevent strokes in generally healthy populations, those same people may still end up suffering from a stroke during a surgery or during/after a major accident or injury. No amount of preventative medication can prevent someone suffering a stroke caused by a brain bleed after a car accident. Likewise for someone with a crush injury, internal bleeding, or broken bones that end up throwing a clot which makes it into the brain.

          So any advancement in halting and reversing damage from a stroke will be a massive boon for emergency medicine until the end of time. Unless of course we somehow find a way to cure/render humans immune to blunt force trauma or lacerations.

          • adastra22 8 hours ago
            Sure you can. Just not with any technology on the horizon. But there is conceivable technology (e.g. medical nanotechnology) that could prevent strokes or stop them as they are happening.
            • lobotomiser 2 hours ago
              Like what?
              • gettingoverit 1 hour ago
                Like detecting constriction or loss of integrity of blood vessels, and doing the corresponding intervention.

                The saddest thing here is not that it requires some future nanotechnology, but is achievable at the present scientific level, yet too expensive to develop, and wouldn't see FDA permission in a decade or two anyway.

        • s5300 7 hours ago
          [dead]
  • MattCruikshank 16 hours ago
    If you've read Ted Chiang's "Understand," you'll understand why this headline made my eyes pop out. For those who haven't, it's in the "Stories of Your Life and Others" collection, which includes the short story that the film Arrival was based on.
    • jadbox 15 hours ago
      I'm a big fan of Ted Chiang's "Understand" short story, but I think your way over hyping the study there: more neuron growth does not even generally translate to higher intelligence and can often introduce a variety of degenerative effects because pathways are not being grown a an organized systematic way through natural process of experience adaptation.
    • TheGRS 15 hours ago
      I just read this a few months ago and it was my first thought as well! Like Flowers for Algernon taken to its extremes.
    • locallost 7 hours ago
      Thanks for the hint. I'd always thought the movie was inspired by Vonnegut's Slaughterhouse 5. The premise was the same, and even the aliens looked somewhat similar. Vonnegut jokingly described them as an upside down toilet brush.
    • naxios_official 16 hours ago
      [flagged]
  • kleton 15 hours ago
  • xbmcuser 8 hours ago
    So my question does it work with Alzheimer's.?
  • hank2000 11 hours ago
    My understanding was that psychedelics have proven to be effective at opening up a “critical period” where a brain can rewire itself like when in childhood. Wonder if this is related.

    https://academic.oup.com/brain/article/148/6/1862/8052899?gu...

  • benoau 19 hours ago
    > “The goal is to have a medicine that stroke patients can take that produces the effects of rehabilitation,” said Dr. S. Thomas Carmichael, the study’s lead author and professor and chair of UCLA Neurology. “Rehabilitation after stroke is limited in its actual effects because most patients cannot sustain the rehab intensity needed for stroke recovery.

    Sounds truly amazing, I have known two people who had severe strokes - one's PT was contingent on triaging resources to whoever was likely to recover more, another simply hated PT and speech therapy and often refused to participate or do the exercises. Even if it didn't help recovery a medicine like this would have reduced the stress of everyone involved.

  • nose 13 hours ago
    Could this treatment also help with other neurodegenerative diseases?
  • trhway 14 hours ago
    > This type of neuron helps generate a brain rhythm, termed a gamma oscillation, which links neurons together so that they form coordinated networks to produce a behavior, such as movement. Stroke causes the brain to lose gamma oscillations. Successful physical rehabilitation in both laboratory mice and humans brought gamma oscillations back into the brain and, in the mouse model, repaired the lost connections of parvalbumin neurons.

    >Carmichael and the team then identified two candidate drugs that might produce gamma oscillations after stroke. These drugs specifically work to excite parvalbumin neurons.

    Asking while being total layperson here - can we generate those gamma oscillations by an [may be implanted] electronic device?

    Edit: and google search to help, judging by the dates seems to be a pretty fresh field :

    https://journals.plos.org/plosbiology/article?id=10.1371/jou...

    "... by pairing robotic rehabilitation with a clinical-like noninvasive 40 Hz transcranial Alternating Current Stimulation, we achieved similar motor improvements mediated by the effective restoring of movement-related gamma band power, improvement of PV-IN maladaptive network dynamics, and increased PV-IN connections in premotor cortex. "

    It also sounds like getting an exoskeleton for such patients can be helpful not only to perform immediate tasks, it also can be a part of the restoring process.

  • 0xWTF 16 hours ago
    ... in male mice.

    I think savvy universities want PIs who are savvy enough to realize that the point of these is to boost measurable visibility like citation count and h-index, so the headline of a news release boosting the article doesn't matter. They can always blame a copy editor for the headlines. It could read "world peace solved with moon juice." The provost would only care if it generated negative feedback. So it's the PR department's job to juice it as much as possible without getting blowback.

    • somewhatgoated 16 hours ago
      Isn’t that where all drugs start out? But yea the headline doesnt tell the full story
      • cwillu 12 hours ago
        “…in mice” isn't a criticism of the science, it's a criticism of the popularization.
      • adastra22 8 hours ago
        There are many drugs that don’t work on mice.
  • nubg 16 hours ago
    How do they test this on mice? Do they trigger brain seizures in them?
    • Traubenfuchs 15 hours ago
      Many different techniques for different types of stroke:

      We can block certain arteries mechanically by inserting a tool, inject photosensitive agent then cause a targeted clot with a laser, inject clotting agent, choke, inject blood vessel dissolving agent and re-inject its own blood.

      I understand why we research this but I just could not do it.

  • martinbfine 11 hours ago
    Neuralink.
  • ninjahawk1 7 hours ago
    [flagged]
  • seabass-salmon 17 hours ago
    [dead]
    • caycep 16 hours ago
      It really depends on how much the company wants to invest. If it really worked, then it would be relatively straightforward for them to put together a Phase II. Not cheap, but relatively straightforward. Or at least it would have been when we had a functioning FDA

      Also, the other definition in question is what the UCLA PR person means by "repairing brain damage". As far as I can tell from the paper - the "drug" part was using some neurotransmitter blockers on brain cells on a Petri dish to see if they could change gene expression or oscillatory firing patterns matching recordings in mice undergoing "physical therapy". They did not actually test to see if the stuff grew new brain cells or dendritic connections.

  • dirtbagskier 17 hours ago
    [dead]
  • KnuthIsGod 16 hours ago
    [flagged]
    • bawolff 16 hours ago
      People go on about this too much. Its the first step, it shows promise.

      Does that mean it will neccesarily work? No, of course not. But its still exciting to see progress being made.

      • bena 15 hours ago
        But it's not progress. Not really.

        Mice are used only partly because they share a considerable amount of DNA with us. But they're mostly used because they're cheap. Both in financial and ethical costs.

        They live for about two years, and breed in about three months. They are disposable. Over 100 million are killed each year in various labs across the country.

        And for all of this, only about 5% of medicine that show positive animal results make it to market in some fashion. So basically, the best thing we can say about a mouse-tested drug is that "this most likely won't make things worse". But that's like a low bar.

        • whatshisface 13 hours ago
          I think there's some kind of fallacy where you can look at five drugs, all of which came from a pool of 100 promising candidates, then look at the next 100 candidates and say for each one individually that it is not worth celebrating. I call it the, "rounding to zero" fallacy.

          In reality, if you have 100 5% chances of a cure for a previously incurable illness, you can celebrate each chance a lot.

          • bawolff 10 hours ago
            > In reality, if you have 100 5% chances of a cure for a previously incurable illness, you can celebrate each chance a lot.

            These numbers are obviously entirely made up, but its worth noting that 100 5% chances of a cure, means you have at least 1 cure with (1-(.95)^100) = 99.4% probability.

            If you are curing an incurable disease with 99.4% probability, celebrating a lot would be an understatement.

            • whatshisface 6 hours ago
              In this example, they're all different diseases.
        • bawolff 12 hours ago
          > And for all of this, only about 5% of medicine that show positive animal results make it to market in some fashion. A mildly positive result is a neccesary but not sufficient condition to make a marketable drug.

          I'm surprised its that high tbh. And i suspect it would be a similar low number if we tested on humans instead of animals.

          And yes, being able to test early stage ideas cheaply is critical to innovating. We use mice in biology for the same reason we use computer simulations in other fields.

          Anyways, if we took your numbers of 5% chance at face value, that means there is a 1 in 20 chance of this press release turning into a real drug that saves real people's lives. Personally i dont think the chance is actually that high, but if it was that would only further my point that this is a milestone worth celebrating.

        • anarticle 11 hours ago
          Hi, sorry, this is so disingenuous of a statement I cannot pass by it without commenting. My bona fides are 10y of lab work, specifically in bioenergetics. I can tell you that 5% is a dramatic UNDERESTIMATION on the value of animal models for medicine at large.

          This is ignoring at least these benefits: surgery, development, genetic studies, grafts, anesthesia, and many MANY more. Some non-drug related, some drug adjacent, and they definitely have downstream benefits to humans.

          Here's a survey paper with myriad examples: https://pmc.ncbi.nlm.nih.gov/articles/PMC9247923/

          I really don't like when bioscience articles land here in HN because they are always commented on with:"in mice", as if to say nothing we see from mouse work works. Well, not everything is software and this kind of work takes years, if not decades. It is real science unfortunately which means that most of it doesn't work! Science, and bioscience specifically, are not efficient systems. In general, the things you do are hard and probably won't work. That doesn't mean you give up.

          Animal models are not great, but they are the best progression we can do right now from cell models. And as for being disposable, there are controls on how animals are used in labs in the US: every institution that has animal experimentation has an IACUC (institutional animal care and use committee) that every research proposal must go through, and they do not a rubber stamp your proposal. They want to know why you can't use cell models, and why you can't do it with less or even no animals.

          It would be nice if people were a bit more even handed when these types of articles come by. I think HN can do better.

          An adage from the lab: "If what we did always worked it would be business, not science."

    • 650REDHAIR 16 hours ago
      You’re right.

      Let’s just skip straight to human trials.

    • functionmouse 16 hours ago
      very happy for those mice
  • mlmonkey 17 hours ago
    Are there any supplements that can work for neurogenesis? I've heard Lions Mane extract can do this, but I'm not sure. Anybody know of anything?
    • toasty228 16 hours ago
      If you don't sleep 8+ hours a day every single day, exercise regularly, live in a place with clean air, eat clean food, don't drink alcohol, etc. you're losing your time, no amount of supplement will make up for our modern way of life, you're going to optimise the 0.1% while missing the 99.9% that matters
      • SilentM68 16 hours ago
        That is true, but keep in mind that routine is very difficult to do for someone that makes their living running the rat race, with stress, no time, responsibilities, worry, untreated health problems, etc. If you have the money, job security, then you'll have peace of mind. That will then allow one to live that kind of optimized lifestyle.
        • rexpop 16 hours ago
          This is why we cannot abide scabs.
          • SilentM68 12 hours ago
            I see your point :)
            • rexpop 12 hours ago
              Self-respect is an act of charity.
    • throwforfeds 17 hours ago
      There's (minimal) research on psilocybin doing just that. One of the tragedies of prohibition is that we just weren't able to study these psychedelic compounds easily for 50+ years.
      • thinkcontext 3 hours ago
        Not to take away from your point about psilocybin but the mushroom brought up, lions mane, is not hallucinogenic.
        • throwforfeds 17 minutes ago
          For sure, and lions mane is one of the three things Paul Stamets has been talking about for years to take in combination with niacin and psilocybin (microdose) to support neurogenesis. Low doses of psilocybin have only very mild perceptual changes, much less than smoking weed or drinking alcohol (for me).
      • grvdrm 14 hours ago
        Have any sources? I’d love to read what you are thinking about.

        I haven’t used psilocybin in a clinical setting but have gone through an alternative psychedelic-assisted therapy process. Very interesting results and many positives.

    • dirtbagskier 17 hours ago
      Cardiovascular exercise and strength training. Both are thought to contribute to neurogenesis, even in healthy people
    • NDlurker 16 hours ago
    • RobotToaster 13 hours ago
    • aeonik 16 hours ago
      Alpha-GPC and Uridine Monophosphate appear to have some effect, though minor. Also not exactly neurogenesis, but adjacent stuff. Evidence is complicated, there seems to be a signal but it's a weak effect.
    • caycep 16 hours ago
      Of note, cautionary tale is too much neurogenesis is brain cancer...
      • dymk 16 hours ago
        No, brain cancer is brain cancer.
        • caycep 14 hours ago
          which is poorly differentiated cells undergoing unchecked neurogenesis...
          • dymk 8 hours ago
            That’s like saying a fire on an oil rig is the same as combustion in a car engine
            • adastra22 8 hours ago
              It’s not as bad an analogy as you make it sound. It is more like “fire is what makes our factories run, and oil fuels fire. So let’s douse our factories in gasoline to speed things up.”
    • SilentM68 12 hours ago
      I've read online that "Bacopa Monnieri" is a particularly strong and researched herbal supplement for cognitive maintenance, enhancement and neuroprotection, with the potential of supporting neurogenesis.

      I've not tried that stuff since money is hard to come by these days. There have been a few human studies.

      You can find more info here:

      https://pubmed.ncbi.nlm.nih.gov/?term=bacopa+monnieri+cognit...

      and here:

      https://www.nccih.nih.gov/health/bacopa-monnieri

    • sysreq_ 16 hours ago
      Nicotine is the only psychoactive substance proven to increase intellectual function. Rote neurogenisis does not - much in the same way height isn’t a proxy for IQ. Stimulants like Adderall, Caffiene, etc are Dunning-Kruger by proxy.
      • oharapj 10 hours ago
        You mean placebo? Not sure that Dunning-Kruger is applicable here
        • sysreq_ 9 hours ago
          Maybe a better term is “stimulant-induced metacognitive miscalibration”. An induced a state of overconfidence similar to Dunning-Kruger - even thought the underlying mechanism is different.

          You perceive the idea as great not because you suddenly understand it better or know more. You think the idea is great because of the dopamine flooding your brain. And much like Dunning-Kruger, even thought you might think you did better, real world results don’t match your expectations.

      • contingencies 12 hours ago
        [flagged]