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Study finds a difference between neurons of humans and other mammals

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Re: Study finds a difference between neurons of humans and other mammals

#71
post #69
post #65

Earlier quoted context omitted.

You can give yourself Bipolar Disoder... https://pubmed.ncbi.nlm.nih.gov/2735813/ It's a blessing and a curse.

Sounds like GP just needs to ingest some anti-lithium.

Several things can trigger calcium channel activity. One of them is Extremely Low Frequency Electromagnetic Fields.

https://www.nature.com/articles/srep21774

Re: Study finds a difference between neurons of humans and other mammals

#72

>They were able to obtain brain tissue from 10 mammalian species: Etruscan shrews (one of the smallest known mammals), gerbils, mice, rats, Guinea pigs, ferrets, rabbits, marmosets, and macaques, as well as human tissue removed from patients with epilepsy during brain surgery. Offbeat question: Could it be that epilepsy is a disorder caused by this missing ion channel, and this isn't true for all humans?

This study does not report that that layer V cortical neurons are missing a particular ion channel. They examine currents through HCN and voltaged-gated potassium channels and find differences in the total current carried that depends on species.

In general, epileptic disorders are observed across species. It's common in dogs, for instance: https://www.akcchf.org/canine-health/top-health-concerns/epi...

A ton of papers examining ion channel expression in epilepsy that should be more relevant: https://pubmed.ncbi.nlm.nih.gov/?term=human+ion+channel+epil...

Re: Study finds a difference between neurons of humans and other mammals

#73

>They were able to obtain brain tissue from 10 mammalian species: Etruscan shrews (one of the smallest known mammals), gerbils, mice, rats, Guinea pigs, ferrets, rabbits, marmosets, and macaques, as well as human tissue removed from patients with epilepsy during brain surgery. Offbeat question: Could it be that epilepsy is a disorder caused by this missing ion channel, and this isn't true for all humans?

Or the ion channel deficit was a side-effect of anti-seizure drugs often given to people with epilepsy, or a side-effect of having seizures, or ... Presumably there is some "gotta be ultra-fresh" reason why they aren't taking just tissue from cadavers donated to medical schools. But this study sounds like it was pretty crappy science, even before the MIT press office folks got hold of it.

I think it should be obvious that you cannot study electrical excitability in dead, fixed cadaver tissue.

This is top-notch science, but might be hard for people to appreciate.

Re: Study finds a difference between neurons of humans and other mammals

#75
post #41
post #39

Earlier quoted context omitted.

> I don't think you understand how science works I have some understanding of how science works. The purpose remains to find plausible explanations to phenomena, explanations that show some solidity. The same value - linked to grounds - remains valid for statements in general. This is why we refine them, in the internal "lab", where they are tried under duress of criticism. Which is scientific process.

And how is "weakening the electric signals between cells makes it easier for cells to alter the message and therefore might give rise to stronger forms of learning" not a plausible link? It costs more energy to ignore a stronger signal, making it harder for cells to learn to change input signals. Humans having weaker signals could therefore be related to our ability to learn, while animals could have stronger signals…

" It costs more energy to ignore a stronger signal," - wait, what, why? Do you have any citation for that? IMHO that has absolutely no basis in how neurons work, it does not cost a cell energy to ignore signals.

"making it harder for cells to learn to change input signals." this sentence is not even wrong; it essentially presumes that the default behavior is to "not change input signals", which is definitely not how neurons work.

"Humans having weaker signals could therefore be related to our ability to learn" - perhaps, but you provide no argument about the direction of causality there (if it's related, perhaps the weaker signals are caused by a different level of learning), nor for elevation of "could be" from mere possibility to why it's likely to be the case.

I'm not saying that there is no way that your hypothesis could be right, but you do need to pass a certain (quite high) bar of clearly stating your assumptions and demonstrating that all of the assumptions are reasonable before your hypothesis would be worth reviewing and evaluating, and there is very a big gap between "possible" and "plausible".

Re: Study finds a difference between neurons of humans and other mammals

#77
post #27

Consider what ion channels are evolutionarily. Gaps between cells. The first proto brains were colonies of cells that lived communally and expressed logic through group dynamics. Think of a colony of cells on a rock under the ocean. As the sun moves across the sky, the cells have to make a decision to move to the more exposed face of the rock to maximise the capture of solar radiation. The cells have to communicate b…

This is, in a sense, a microcosm of the argument in Daniel Dennet’s “Consciousness Explained.” To oversimplify (and potentially butcher): consciousness results from innumerable “drafts” or guesses arising from neural interpretation of sensory input. From Wikipedia, describing the book: ‘The brain consists of a "bundle of semi-independent agencies";[3] when "content-fixation" takes place in one of these, its effects m…

Picked up this book just now... Seems full of red flags. In the first few pages:

- Accepts Descartes' "I think, therefore I am" without skepticism

- Aims for a scientific theory to be "respectable"

- Concludes that because sensory input to a brain seems infeasible using 1990 simulation tech (Not considering advances, using sensors etc), simulating reality to a brain isn't possible; Makes a comparison to a ladder-to-the-moon.

Re: Study finds a difference between neurons of humans and other mammals

#79
post #11

>They were able to obtain brain tissue from 10 mammalian species: Etruscan shrews (one of the smallest known mammals), gerbils, mice, rats, Guinea pigs, ferrets, rabbits, marmosets, and macaques, as well as human tissue removed from patients with epilepsy during brain surgery. Offbeat question: Could it be that epilepsy is a disorder caused by this missing ion channel, and this isn't true for all humans?

If true, that would be an embarrassing oversight in the study as well as possibly #1 in one of those "Top 10 accidental scientific discoveries that changed everything" articles.

> To limit the potential confound of disease states associated with our human brain samples, we compared the biophysical properties of neurons from patients with hippocampal sclerosis; tumour; and other conditions, including gliosis and trauma. We found no significant differences in somatic outside-out currents between the three groups (Extended Data Fig. 7). We also directly tested the effect of epileptic seizures on somatic ionic conductance in rats and found no significant differences (Extended Data Fig. 7). Together, these results suggest that disease aetiology is unlikely to underlie the distinct features of human L5 neurons such as their low conductance.

Re: Study finds a difference between neurons of humans and other mammals

#80
post #27

Earlier quoted context omitted.

This is, in a sense, a microcosm of the argument in Daniel Dennet’s “Consciousness Explained.” To oversimplify (and potentially butcher): consciousness results from innumerable “drafts” or guesses arising from neural interpretation of sensory input. From Wikipedia, describing the book: ‘The brain consists of a "bundle of semi-independent agencies";[3] when "content-fixation" takes place in one of these, its effects m…

Picked up this book just now... Seems full of red flags. In the first few pages: - Accepts Descartes' "I think, therefore I am" without skepticism - Aims for a scientific theory to be "respectable" - Concludes that because sensory input to a brain seems infeasible using 1990 simulation tech (Not considering advances, using sensors etc), simulating reality to a brain isn't possible; Makes a comparison to a ladder-to-t…

Hmm... those seem like pretty shallow interpretations of his research.

What do you mean by 'accepts Descartes' "I think, therefore I am" without skepticism?'

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