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> They identified two different brain progenitor cells. One, which expresses a gene called Otx2, is destined to become the forebrain and midbrain. The other, which expresses a gene called Gbx2, is committed to forming the hindbrain. They showed that these two cell populations never overlap; they are mutually exclusive from the earliest stages of development.
Very cool. Never thought the brain could have two completely different ancestors
"Nervous systems are typically defined as networks of neurons that communicate across synapses. But Burkhardt’s lab found something unique in ctenophores: Beneath the animal’s outer surface is a nerve net (pink mesh in this 3D reconstruction) whose neurons are connected by continuous cytoplasm — but with no synapses between them. “I don’t think any other animal has a nervous system like that,” Burkhardt said. Because ctenophores are one of the earliest branches of the animal family tree, the finding indicates that evolution may have crafted nervous systems twice: in ctenophores, and separately in jellyfish and all other animals."
Like the thought:) But actually have read that the hypothesis that the hindbrain (or lower brain) had evolved directly from our lizard ancestors while the upper brain (which does more complex types of thought) evolved later turned out to be wrong. Like the study has shown, they evolved at the same time, and many animals had both. It's just in humans, the upper brain evolved much larger in proportion to the lower brain.
The press release does somewhat overhype up the actual finding though. The actual finding is that different parts of the brain arise from different neural ectoderm progenitors, which explains why it’s so hard to get a forebrain neuron to behave like a hindbrain neuron and vice versa in the lab. The paper then postulates that this difference in progenitors resembles being two different organs evolutionarily, but this is not really the most important part of the paper.
* Different brain regions have different functions: ancient knowledge.
* Different regions contain distinct cell types and molecular programs: also well established.
* Anterior and posterior brain structures may trace back to fundamentally separate progenitor lineages that were independently specified very early in evolution and development: that's the interesting new result.
The headline should have been: "Human forebrain and hindbrain arise from distinct embryonic progenitor lineages" - not that we have "two organs" in the brain.
Given the parallel example cited in the article of jellyfish having two spatially separate organs, & the subsequent speculation that our own ancestors could also have had spacially separate anterior & posterior masses, the title doesn't really seem unreasonable in its hyperbole.
While it might not be perfectly accurate it's hardly misleading.
I found the title confusing, at the very least because it can be argued that the two brain hemispheres are two organs already, as they operate independently when severed from each other.
This is not a good analogy, because both kidneys do the same thing and we don't need both of them to live.
Whereas the left and right brain hemispheres do different things that enable enable our species to be what it now is; which is more similar to what the article calls hind and fore/front brains, which again do different things that we wouldn't be using without. We would still be human if we had only one kidney the way we have only one bladder or one pancreas.
Kidneys are more like say lungs, gonads, breasts, or nostrils in that we have +1 extra; but the benefit created by multiplicity is ~doubling or capacity and resilience to local disease and random injury-- not a profound functionality. (Like is created by the second eye or second leg.) Of these, the second breast is radically more useful than the second kidney, and is probably a special case as it changes how we live so evolved.
The right and left hemispheres do different things… unless you had a hemispherectomy as an infant and then one half is able to mostly perform the duties of both.
I wonder if we would have been capable of endurance hunting without both lungs. I suspect that changing that would have very drastically changed human development.
> I want to trust science and dislike anti vaxxers but it’s difficult to argue against them when researchers act like the caricature they are mocked as.
Wait, you think the article was written by the researchers?
You know, it's also difficult to trust someone's criticisms when they misassign responsibility. Just like anti-vaxxers do.
> "Human forebrain and hindbrain arise from distinct embryonic progenitor lineages"
I'd have never clicked that headline nor understood why this finding is important.
If you think the original headline is not "truthful" enough, at least do something like "Researchers found the reason why hindbrain cells cannot be grown in a lab and found a way to overcome it"
> not that we have "two organs" in the brain.
Depends what the definition of "organ" actually is. What speaks for different organs here is that the cells both have a different pathway from stem cells and have different evolutionary histories. That is different from other brain regions that may have separate functions but still evolved together.
You stated that the current headline informs you why the result is important. Why is that? Surely, given that the information was communicated to you, you can share it with me?
We should not be wary of loud truths either. Unless we push the envelope we cannot trace back to the essence. Like, as an outsider in this discussion, I am now inclined not only to assess the finding, but also the definition of an organ. The title did good work. Its refutation too. Fencing every statement in unquestionable truth does not make the pursuit of truth stronger.
But there’s rarely one correct answer. Conveying the same approximate message to multiple types of readers is extremely difficult in a handful of words. People with subject matter knowledge are annoyed by headlines written for laypeople that don’t know the jargon or have a mental model of the important concepts that jargon represents. They always seem to miss important distinctions, make poor analogies, or the like. Headline-length blurbs that successfully convey those things to the knowledgeable are often utterly opaque to laypeople causing them to ignore articles about topics they’d find interesting. The only option is trying to estimate the subject matter expertise of the audience, and despite many people in the tech world assuming their software knowledge gives them technical expertise in many non-software fields, the layperson headline is absolutely the best approach here.
This is not true. There is a complex relationship between truth and good communication. The relationship is non linear and convoluted and it depends often on the subject of what is being communicated.
There are many many cases where lies are easier to communicate than the truth.
Take tobacco for instance. For the longest time we did not know it was bad for you. It took decades of epidemiological research and statistical techniques to ascertain that it was bad.
The truth was buried in numbers and human knowledge about applied mathematics and statistics. Without centuries of human endeavor to create the concept of science unionized with the rigor of statistics the truth would have remained forever invisible.
The sheer complexity of the truth in this case makes is extremely hard to communicated we trust that smoking based off of the reputation of the researchers who established the fact. But the truth was never really directly communicated to most of us as it involves diving deep into the data.
The truth about tobacco was known for years but ignored because 1) industry lobbying and 2) the Nazis were the ones who figured it out, and pushed anti-smoking hard, so smoking became something "our side" did, 3) tobacco was still a huge US export.
It was easy to communicate, but we were motivated to not listen.
No the deaths were buried deep in the statistical data. It’s not apparent and we did not know either way.
Yes there were people who said it’s bad but their word was as good as bullshit because until we had the statistics there is literally no way to truly know.
No, the Germans had good statistical data linking smoking (as well as asbestos and other carcinogens) to cancer by the 1930s; this was known and ignored (or actively derided) by the allies. It's one of the classic and well known examples of ad hominem.
> There is a complex relationship between truth and *good* communication. [...] There are many many cases where lies are *easier to communicate* than the truth.
You're literally conflating good communication with easy communication.
> Armed with this knowledge, the researchers for the first time successfully coaxed human pluripotent stem cells (a kind of cell that can create any cell in the human body) to become functional hindbrain motor neurons in the laboratory.
...
> The research also has implications for investigating treatments for SMA, ALS and other conditions affecting the brain stem. Until now, studying these diseases has been nearly impossible because scientists cannot obtain brain stem tissue from living patients. The ability to grow these neurons in a dish opens new possibilities for understanding what goes wrong.
But no, nothing to see here, not worth our time for this overblown article apparently ...
I don't have a problem with the 'two organs making one' framing. The fact that they are 'symbiotic' now doesn't change that. In fact it helps me understand two key facts. One can't grow out of the other, and they work differently. Great
The Portuguese Man o’ War[0] is a symbiotic organism. If you want to get technical, I guess we are, as well. We’re really kind of fascinating meatbags.
We are absolutely symbiotic from our cells upward. A large percentage of your body mass is bacteria, including the symbiotic bacteria you feed in your gut with the food you think you’re eating only for yourself.
Main issue I have with the title is it immediately reminded me about McGilchrist's "The Divided Brain" and I thought they meant the two halves - but that is not the case.
This is meaningless semantic drama over a meaningful discovery. From a biological and medical perspective, the collective term "organ" is pretty useless, if there is a distinct progenitor lineage. For the sake of a simplified explanation for the public, describing this discovery as finding "two organs" is absolutely fair.
A similar example: The melanocytes in the skin originate from the neural crest, not the epidermis. As a significant consequence, melanocytes share cell attributes with neurons. One of these attributes is the ability to infiltrate other tissues. Because of that, malignant transformation of melanocytes has vastly different consequences, compared to epithelial cells. If you asked your doctor why squamous cell cancer and melanoma have such different prognoses, describing your skin as effectively "two organs" would be illustrative and easy to understand, without getting into developmental biology.
I think you're right. And I would even assume that, should the article be from Fox News (just an example), every other commenter that excuses the title would have yelled at journalism slop, clickbait and whatnot.
But that's stanford.edu, so we must tread lightly.
I've found it useful to think in terms of how such structures might have evolved. The beginning state is always something very simple: the first nerve. It must go from A to B. Perhaps from a food sensing area to a muscle. Sense food, stop moving, something like that. Organisms could evolve multiple copies of that structure: N nerves going from A(n) to B(n). At some point the next invention arises: some logic gate type thing that branches and/or combines nerves. So now sensing food can make movement stop and also digestion begin. Or food response can be attenuated during the day time. And so on. There's no reason why you'd have exactly one of these "nerve processor" nodes. There's also no reason why several different kinds of them and different instances might evolve. They're useful. Then at some point the next discovery is made: by combining several nerve processor nodes in close proximity, with their own inter-node connections, you can perform more complex processing. You've now got a proto-brain. But again there's nothing to say you have exactly one of these things, or that they're exact replicas of each other.
I'm sorry, it just sounds like you're mad at medical researcher for trying to make their research more accessible?
What do you mean by oversell? And why do you think the general public would be more apt to understand "distinct embryonic progenitor lineages" than "two organs"?
What exactly is the problem here? You think medical researcher are using medial nomenclature wrong?
Agreed. Anybody who looks at a picture of the brain can see the cerebellum (part of the hindbrain) is obviously a different organ. I only clicked the link to find out if there was any new science buried under the hype of the title.
They also use this result to great hindbrain neurons in the lab for the first time, so it's a strikingly useful discovery.
I think it's also fair to say they are different organs based on the developmental physiology. Many other organs come from distinct embryonic cell lines.
When an organ is known to be generated from 2 distinct embryonic preforms, which become merged and integrated at a later stage of development, there is a likelihood that in some distant ancestor the integration into a single organ was much less advanced than now and possibly the two parts remained as relatively separated organs even during adulthood.
In this case it is not known for sure what happened, because the early evolution of the nervous system, from a sensory structure embedded in the skin to a complex internal system that mediates the communication between sensors and motor or secretory organs, is still poorly understood.
Yeah, this is a frequent failure of science communication. Misleading clickbait overselling a paper that made real progress in some capacity. I'd be more interested in hearing the truth of the matter and about the researchers passion for their study area. Spinning everything into some high stakes breakthrough that fundamentally changes our understanding of the world just makes me feel like my time was maliciously wasted and that I shouldn't click on news about science.
can confirm from experience that the headline and press release were likely 100% from Stanford’s comms department and the authors are likely panicking about the hyperbolic spin
When I studied neuroanatomy in the early 2000s it was already taught that the evolutionary history of the forebrain (from comparative anatomy) seems to have invaded the hindbrain and seems to control it like a puppet. It's nice to see this sort of confirmation but it doesn't strike me as an earth-shaking discovery except that it might give some insights for differential drug targeting.
This is one of the problems with modern academics, every paper has to be framed as some revolutionary idea or insight. We should celebrate “boring” research that serves nothing other than curiosity.
Academics themselves rarely frame their research in sensational terms. This happens in press releases and media coverage, which they have little control over. You can see this by comparing the title of the press release to the quotes by the actual researchers:
"We’ve shown for the first time that the front of the brain arises from a totally different progenitor cell than the back of the brain."
"I was surprised at our findings because the word ‘brain’ implies a contiguous organ that likely has a singular origin," Jokhai said. "But even 500 million years ago, there were these separate neural systems, which now almost operate as one, which is very cool."
I don't hear much overselling or hype in this, I hear an accurate description of the research and a bit of nerding out over it.
It's the same problem as when a journalist or nonfiction author writes a thoughtful, nuanced piece of work, and some editor slaps a catchy title and subtitle on.
A physical connection and collaborative function aren't enough to define a single organ anymore. It must also share a developmental and evolutionary origin.
The audience for a news headline is a layperson who may have no knowledge of or context to infer past factoids about brain regions or evolutionary biology.
There’s a balance between being informative to the audience and satisfying for pedants.
>The headline should have been: "Human forebrain and hindbrain arise from distinct embryonic progenitor lineages" - not that we have "two organs" in the brain.
It's cool, but the headline is really pretty misleading.
The new result seems to be that researchers have identified different progenitors for fore/midbrain vs. hindbrain and have found that they can be identified by some specific developmental gene markers. That's genuinely cool.
However, organs are not typically defined by a single tissue characterized by a progenitor that can be labeled with a single gene marker. I suppose it's fine if on a functional and anatomical level you want to split the fore/midbrain and hindbrain into two different "organs", but whether you think of the brain as 1 organ or 2, it really doesn't change much in terms of how you would think about these regions.
It isn't at all surprising that different regions of the brain have localized functions; some of the earliest evidence of this was how focal injuries (like strokes) have characteristic deficit patterns depending on brain region affected, and obviously there has been a lot of work since then further showing the organization, function and development of different brain regions.
The really exciting thing in this article is that this research led them to a new technique for growing brain stem cells in vitro, which has been very difficult until now. If that isn't being oversold, it's big news. That's going to make future research into diseases like ALS a lot easier.
It really fascinates me how dumb HN community is considering they know nothing about brain on the level of actual experts yet readily comment it as “non important” based on vibes.
If this is not your area of expertise why comment with stunning confidence on something you have no idea about?
And actually, the fact that brain is actually two "developmental" systems combined into one seems like big news to me. We might not know it's other uses, but probably for cognitive science and even AI research this might be super useful. In AI, maybe two models should be developed and trained in conjunction that talk to each other, each with different functions and roles, because brains work better this way.
And from what I read, evolution did this a somewhat often. The parts of the ear evolved from different "Gill slits" from when we were fish (meaning the ear isn't evolved from one group of cells in the embryo, but from multiple groups of cells that evolved into one organ system, the ear).
Title: "Two parallel neural ectoderm progenitors contribute to the developing brain".
"Hence, we postulate the brain is a composite organ emanating from two lineage-restricted progenitors; these dual progenitors may be evolutionarily conserved across 550 million years from hemichordates to mammals."
> The new research finding shows that the human brain consists of two ancient nervous systems cleverly packaged together — a more primitive part that regulates our hearts’ beating, our breathing and other functions, and another that makes us distinctly human, capable of poetry, mathematics and wondering about our own origins.
I'm not sure the actual article in Nature Neuroscience [1] actually says that. I remember "Your Brain Is Not an Onion With a Tiny Reptile Inside" [2] from a few years ago, but I'm not sure where the dissonance comes from: my own misunderstanding, the press release using a popular but flawed model to communicate with laymen, or these two articles being in direct contradiction with each other?
Interesting, but for me at least, this new research did not seem to promote the dispelled hypothesis about the reptile brain. Because the reptile brain hypothesis says a primitive reptile-brain evolved first (lower brain), then a separate part of the brain (upper brain) evolved later that was responsible for complex thought.
Actually, the upper and lower brains evolved together and most animals have both, including reptiles.
Didn't read it thoroughly, but your [2] reference seems to be saying this too.
What is the difference between saying that the brain is two organs, as in the title, or a "composite organ" as in the actual paper? What makes an organ a single autonomous organ?
The digestive tract could also be seen as a single organ since they are connected. I think the deciding criteria should be the one applied in this study, i.e., how an organ develops.
The cerebellum isn't just for motor skills. It's more of a place where very commonly used patterns get a bunch of dedicated wetware so the computation is superfast and precise. In an (undoubtedly very limited) analogy a bunch of FPGAs to complement the general processing. It does make a lot of sense to use this functionality for motor skills, though.
It's spent on 'fast, effortless' recall. Maybe, long-term memory, or memories associated with activities like balance, singing, and anything that requires precise steady control. A keeper of balance and rhythm, if you want to think of it that way, and anything that is too much of a burden to creativity: a mind is a bunch of ideas (thoughts) collected into a moment in the mind, all the ones needed for controlling things like balance and rhythm are best handled in an autonomously looped fashion.
The article mentions the forebrain controls creativity, reasoning, higher-level thinking. And the hindbrain controls muscles of the throat, tongue, etc: so speech, singing.
But when someone sings or speaks, they obviously engage the frontbrain's creative functions in order to know 'what results are considered good to me'. We judge our output, and adjust accordingly through practice and lessons.
Everything becomes an autonomous loop: which is the study of Cybernetics, and (coincidentally?) the birthplace of AI.
All the comments I see are about is it two organs, or a composite organ.
Surely the interesting thing is the ability to grow hindbrain cells in vitreo. That's what's potentially going to lead to the cure of lots of things, not whether 1=2.
There is some truth (but not accuracy) to it, but not for this reason.
This article is about brainstem (aka hindbrain) vs the rest (midbrain + forebrain).
Evolutionally older animal lineages like fish, reptiles, birds all have midbrain + forebrain as well as the brainstem, so reptilian brain != brainstem.
Where there is some truth to our older "reptilian" brain is that the part of the forebrain called the pallium, that exists even in fish (& reptiles), has much expanded/evolved in mammals giving us our cortex and hippocampus, so you could kinda say that we have a reptilian brain + cortex. Note though that mammals didn't evolve from reptiles - they evolved in parallel from a common ancestor, so maybe better to say we have a fish brain + cortex (& hippocampus).
While the cortex is what gives mammals their intelligence, in birds the pallium evolved in a different way to give them theirs.
am no expert in brain development, still have read about evolution. I like aspects of the way you mentioned this, but seems that putting cortex separately from fish brain isn't quite right. As you mentioned, the cortex is simply a part of the fish brain that evolved much (much, much) larger than a fish's. Maybe:
Fish Brain = brain stem + small cortex (+ other parts of brain)
|
(evolved into)
|
V
Human Brain = brain stem + gigantic cortex (+ other parts of brain)
Sorry, know this is splitting hairs, but just thought it an interesting distinction to make.
That's not quite right - a fish does not have a cortex.
The pallium of a fish and mammal are structured differently. A fish's (& bird's) pallium has a clustered (aka "nuclear") organization, while a mammal's has a mostly layered organization which is what is referred to as the cortex.
There is also more to a brain than just brainstem + pallium. In a vertebrate it's brainstem (aka hindbrain) + midbrain + forebrain, with the pallium being part of the forebrain.
I don’t think the medical community has believed as the article claims for nearly a century.
Most animal brains have three very different organs in the brain: the cerebrum, cerebellum, and the limbic system (which itself is further divided into numerous differentiated types of tissues)
that's funny when I was in junior school, 15 years ago, I said in the classroom during science class, that we have 2 brains. everyone including my teacher were laughed at me.
There's a very interesting split-brain experiment [1] and Joe Scott's video about it [2]
TL;DW: Doctors treated corpus callosotomy by severing the bundle of nerve fibers that connect hemispheres of the brain. The surgery effectively stopped seizures from spreading. Left hemisphere handles language, speech, and logical interpretation, right hemisphere handles visual, spatial, and literal tasks.
Because human eyes send visual information to opposite sides of the brain, researchers could show images only to the non-speaking right brain. The right brain could see and physically react to the image (like picking up a matching object with the left hand), but the patient couldn't verbally explain what they were seeing because the left brain was literally in the dark. Instead of saying "I don't know," the speaking left brain would instantly and confidently invent a logical—but completely fake—justification for the action.
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[0] https://www.biorxiv.org/content/10.1101/2025.07.02.662771v2
PDF is free to download.
Very cool. Never thought the brain could have two completely different ancestors
"Nervous systems are typically defined as networks of neurons that communicate across synapses. But Burkhardt’s lab found something unique in ctenophores: Beneath the animal’s outer surface is a nerve net (pink mesh in this 3D reconstruction) whose neurons are connected by continuous cytoplasm — but with no synapses between them. “I don’t think any other animal has a nervous system like that,” Burkhardt said. Because ctenophores are one of the earliest branches of the animal family tree, the finding indicates that evolution may have crafted nervous systems twice: in ctenophores, and separately in jellyfish and all other animals."
We fail to imagine how much time takes to „craft a nervous system”.
Super scary how small are we in big scheme of things.
at one point I learned that it would only take a few hundred thousand years to evolve an eye, and time felt much deeper.
https://thebrainscientist.com/2018/04/11/you-dont-have-a-liz...
But yeah, evolution is fascinating.
All parts of the body are built like this. Otherwise we would be blobs.
Before becoming two parts they probably were part of the same parent protobrain tissue.
If you told me the hindbrain was ectoderm-derived but the forebrain was endoderm-derived, I might raise an eyebrow or two.
Please name one other organ that arises from two separate progenitor cell types. If this is common, I have never heard of it.
Article says they weren't.
Science movies forward yet again with a few backward steps.
https://www.nature.com/articles/s41593-026-02433-7
The press release does somewhat overhype up the actual finding though. The actual finding is that different parts of the brain arise from different neural ectoderm progenitors, which explains why it’s so hard to get a forebrain neuron to behave like a hindbrain neuron and vice versa in the lab. The paper then postulates that this difference in progenitors resembles being two different organs evolutionarily, but this is not really the most important part of the paper.
watson and crick's paper was not peer reviewed, neither were darwin's papers.
not sure what you think happens in peer review but it's probably overrated.
One problem is that there's no good incentive to spend significant time doing good peer review.
Darwin wrote his book Origin of Species the following year.
The reality is:
The headline should have been: "Human forebrain and hindbrain arise from distinct embryonic progenitor lineages" - not that we have "two organs" in the brain.While it might not be perfectly accurate it's hardly misleading.
Whereas the left and right brain hemispheres do different things that enable enable our species to be what it now is; which is more similar to what the article calls hind and fore/front brains, which again do different things that we wouldn't be using without. We would still be human if we had only one kidney the way we have only one bladder or one pancreas.
Kidneys are more like say lungs, gonads, breasts, or nostrils in that we have +1 extra; but the benefit created by multiplicity is ~doubling or capacity and resilience to local disease and random injury-- not a profound functionality. (Like is created by the second eye or second leg.) Of these, the second breast is radically more useful than the second kidney, and is probably a special case as it changes how we live so evolved.
TIL, gosh!
The most important question: are they all conscious?
I want to trust science and dislike anti vaxxers but it’s difficult to argue against them when researchers act like the caricature they are mocked as.
Self aggrandizing articles with misleading headlines is giving me 2 triggers for not trusting the content.
Wait, you think the article was written by the researchers?
You know, it's also difficult to trust someone's criticisms when they misassign responsibility. Just like anti-vaxxers do.
My apologies to the researchers
When submitting, one can try to replace the title with something honest. HN does not favor that, mostly due to submitters having their own biases.
The best tactic is finding a higher quality article on the subject, to submit instead. That's uncertain, takes time, and may run into paywall issues.
"Elon Musk's Brain is Two Separate Organs"
I'd have never clicked that headline nor understood why this finding is important.
If you think the original headline is not "truthful" enough, at least do something like "Researchers found the reason why hindbrain cells cannot be grown in a lab and found a way to overcome it"
> not that we have "two organs" in the brain.
Depends what the definition of "organ" actually is. What speaks for different organs here is that the cells both have a different pathway from stem cells and have different evolutionary histories. That is different from other brain regions that may have separate functions but still evolved together.
Why do you think it's important?
But that finding is a direct consecutive of the "cerebellum is a different organ" finding from the headline.
The findings arn't exactly "new" but the medical science about it is definitely lagging current research.
There are many many cases where lies are easier to communicate than the truth.
Take tobacco for instance. For the longest time we did not know it was bad for you. It took decades of epidemiological research and statistical techniques to ascertain that it was bad.
The truth was buried in numbers and human knowledge about applied mathematics and statistics. Without centuries of human endeavor to create the concept of science unionized with the rigor of statistics the truth would have remained forever invisible.
The sheer complexity of the truth in this case makes is extremely hard to communicated we trust that smoking based off of the reputation of the researchers who established the fact. But the truth was never really directly communicated to most of us as it involves diving deep into the data.
It was easy to communicate, but we were motivated to not listen.
Yes there were people who said it’s bad but their word was as good as bullshit because until we had the statistics there is literally no way to truly know.
You're literally conflating good communication with easy communication.
Does this finding change your life in any meaningful way?
...
> The research also has implications for investigating treatments for SMA, ALS and other conditions affecting the brain stem. Until now, studying these diseases has been nearly impossible because scientists cannot obtain brain stem tissue from living patients. The ability to grow these neurons in a dish opens new possibilities for understanding what goes wrong.
But no, nothing to see here, not worth our time for this overblown article apparently ...
[0] https://en.wikipedia.org/wiki/Portuguese_man_o%27_war
So the question still remains...
https://www.ted.com/talks/iain_mcgilchrist_the_divided_brain
A similar example: The melanocytes in the skin originate from the neural crest, not the epidermis. As a significant consequence, melanocytes share cell attributes with neurons. One of these attributes is the ability to infiltrate other tissues. Because of that, malignant transformation of melanocytes has vastly different consequences, compared to epithelial cells. If you asked your doctor why squamous cell cancer and melanoma have such different prognoses, describing your skin as effectively "two organs" would be illustrative and easy to understand, without getting into developmental biology.
But that's stanford.edu, so we must tread lightly.
Comments somewhere down below has details.
What do you mean by oversell? And why do you think the general public would be more apt to understand "distinct embryonic progenitor lineages" than "two organs"?
What exactly is the problem here? You think medical researcher are using medial nomenclature wrong?
Honestly write a paper about it then.
I wanted a drawing, but was disappointed.
I think it's also fair to say they are different organs based on the developmental physiology. Many other organs come from distinct embryonic cell lines.
When an organ is known to be generated from 2 distinct embryonic preforms, which become merged and integrated at a later stage of development, there is a likelihood that in some distant ancestor the integration into a single organ was much less advanced than now and possibly the two parts remained as relatively separated organs even during adulthood.
In this case it is not known for sure what happened, because the early evolution of the nervous system, from a sensory structure embedded in the skin to a complex internal system that mediates the communication between sensors and motor or secretory organs, is still poorly understood.
The article did change an understanding about worlds though, it's just the inner one. I thought the article title was ok.
Also newspaper headlines used to give a quick summary of the story, online articles as you say, clickbait.
It’s so small as to be a non-problem, in my view. Attention-seekers are gonna do what they do. Meanwhile the work accumulates.
"We’ve shown for the first time that the front of the brain arises from a totally different progenitor cell than the back of the brain."
"I was surprised at our findings because the word ‘brain’ implies a contiguous organ that likely has a singular origin," Jokhai said. "But even 500 million years ago, there were these separate neural systems, which now almost operate as one, which is very cool."
I don't hear much overselling or hype in this, I hear an accurate description of the research and a bit of nerding out over it.
There’s a balance between being informative to the audience and satisfying for pedants.
Well we see why you're not a journalist.
The new result seems to be that researchers have identified different progenitors for fore/midbrain vs. hindbrain and have found that they can be identified by some specific developmental gene markers. That's genuinely cool.
However, organs are not typically defined by a single tissue characterized by a progenitor that can be labeled with a single gene marker. I suppose it's fine if on a functional and anatomical level you want to split the fore/midbrain and hindbrain into two different "organs", but whether you think of the brain as 1 organ or 2, it really doesn't change much in terms of how you would think about these regions.
It isn't at all surprising that different regions of the brain have localized functions; some of the earliest evidence of this was how focal injuries (like strokes) have characteristic deficit patterns depending on brain region affected, and obviously there has been a lot of work since then further showing the organization, function and development of different brain regions.
If this is not your area of expertise why comment with stunning confidence on something you have no idea about?
Ego?
And actually, the fact that brain is actually two "developmental" systems combined into one seems like big news to me. We might not know it's other uses, but probably for cognitive science and even AI research this might be super useful. In AI, maybe two models should be developed and trained in conjunction that talk to each other, each with different functions and roles, because brains work better this way.
And from what I read, evolution did this a somewhat often. The parts of the ear evolved from different "Gill slits" from when we were fish (meaning the ear isn't evolved from one group of cells in the embryo, but from multiple groups of cells that evolved into one organ system, the ear).
https://www.nature.com/articles/s41593-026-02433-7
Title: "Two parallel neural ectoderm progenitors contribute to the developing brain".
"Hence, we postulate the brain is a composite organ emanating from two lineage-restricted progenitors; these dual progenitors may be evolutionarily conserved across 550 million years from hemichordates to mammals."
I'm not sure the actual article in Nature Neuroscience [1] actually says that. I remember "Your Brain Is Not an Onion With a Tiny Reptile Inside" [2] from a few years ago, but I'm not sure where the dissonance comes from: my own misunderstanding, the press release using a popular but flawed model to communicate with laymen, or these two articles being in direct contradiction with each other?
[1]: https://www.nature.com/articles/s41593-026-02433-7 [2]: https://journals.sagepub.com/doi/10.1177/0963721420917687
Actually, the upper and lower brains evolved together and most animals have both, including reptiles.
Didn't read it thoroughly, but your [2] reference seems to be saying this too.
In other words: only <20% of pur neuron budget goes to higher cognition (thinking, language, seeing, hearing). 80% is spent on motor skills.
The cerebellum isn't just for motor skills. It's more of a place where very commonly used patterns get a bunch of dedicated wetware so the computation is superfast and precise. In an (undoubtedly very limited) analogy a bunch of FPGAs to complement the general processing. It does make a lot of sense to use this functionality for motor skills, though.
See:
- https://pmc.ncbi.nlm.nih.gov/articles/PMC4089997/
- https://pubmed.ncbi.nlm.nih.gov/38663092/
The article mentions the forebrain controls creativity, reasoning, higher-level thinking. And the hindbrain controls muscles of the throat, tongue, etc: so speech, singing.
But when someone sings or speaks, they obviously engage the frontbrain's creative functions in order to know 'what results are considered good to me'. We judge our output, and adjust accordingly through practice and lessons.
Everything becomes an autonomous loop: which is the study of Cybernetics, and (coincidentally?) the birthplace of AI.
Surely the interesting thing is the ability to grow hindbrain cells in vitreo. That's what's potentially going to lead to the cure of lots of things, not whether 1=2.
This article is about brainstem (aka hindbrain) vs the rest (midbrain + forebrain).
Evolutionally older animal lineages like fish, reptiles, birds all have midbrain + forebrain as well as the brainstem, so reptilian brain != brainstem.
Where there is some truth to our older "reptilian" brain is that the part of the forebrain called the pallium, that exists even in fish (& reptiles), has much expanded/evolved in mammals giving us our cortex and hippocampus, so you could kinda say that we have a reptilian brain + cortex. Note though that mammals didn't evolve from reptiles - they evolved in parallel from a common ancestor, so maybe better to say we have a fish brain + cortex (& hippocampus).
While the cortex is what gives mammals their intelligence, in birds the pallium evolved in a different way to give them theirs.
Fish Brain = brain stem + small cortex (+ other parts of brain)
Human Brain = brain stem + gigantic cortex (+ other parts of brain)Sorry, know this is splitting hairs, but just thought it an interesting distinction to make.
The pallium of a fish and mammal are structured differently. A fish's (& bird's) pallium has a clustered (aka "nuclear") organization, while a mammal's has a mostly layered organization which is what is referred to as the cortex.
There is also more to a brain than just brainstem + pallium. In a vertebrate it's brainstem (aka hindbrain) + midbrain + forebrain, with the pallium being part of the forebrain.
Most animal brains have three very different organs in the brain: the cerebrum, cerebellum, and the limbic system (which itself is further divided into numerous differentiated types of tissues)
TL;DW: Doctors treated corpus callosotomy by severing the bundle of nerve fibers that connect hemispheres of the brain. The surgery effectively stopped seizures from spreading. Left hemisphere handles language, speech, and logical interpretation, right hemisphere handles visual, spatial, and literal tasks.
Because human eyes send visual information to opposite sides of the brain, researchers could show images only to the non-speaking right brain. The right brain could see and physically react to the image (like picking up a matching object with the left hand), but the patient couldn't verbally explain what they were seeing because the left brain was literally in the dark. Instead of saying "I don't know," the speaking left brain would instantly and confidently invent a logical—but completely fake—justification for the action.
[1]: https://en.wikipedia.org/wiki/Split-brain [2]: https://www.youtube.com/watch?v=_TYuTid9a6k