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All things brain...

Started by Claireliontamer, July 12, 2017, 08:18:49 PM

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Icarus

Here is a junior varsity theory about the development of language as a necessity for teaching tool making.  Maybe a bit too simplistic but an easy read.
https://getpocket.com/explore/item/a-sneaky-theory-of-where-language-came-from?utm_source=pocket-newtab

Recusant

A new MRI study indicates that the surface area of the human cerebellum is greater than had previously been thought.



"'Little brain' or cerebellum not so little after all" | ScienceDaily

Quote

Cerebellum highlighted in illustration of brain. Image credit: © decade3d / stock.adobe.com




When we say someone has a quick mind, it may be in part thanks to our expanded cerebellum that distinguishes human brains from those of macaque monkeys, for example.

Sometimes referred to by its Latin translation as the '"little brain"', the cerebellum is located close to the brainstem and sits under the cortex in the hindbrain. New research at San Diego State University, however, calls the "little" terminology into question.

The cerebellum plays a versatile role, contributing to our five senses as well as pain, movements, thought, and emotion.

It's essentially a flat sheet with the thickness of a crepe, crinkled into hundreds of folds to make it fit into a compact volume about one-eighth the volume of the cerebral cortex. For this reason, the surface area of the cerebellum was thought to be considerably smaller than that of the cerebral cortex.

By using an ultra-high-field 9.4 Tesla MRI machine to scan the brain and custom software to process the resulting images, an SDSU neuroimaging expert discovered the tightly packed folds actually contain a surface area equal to 80% of the cerebral cortex's surface area. In comparison, the macaque's cerebellum is about 30% the size of its cortex.

"The fact that it has such a large surface area speaks to the evolution of distinctively human behaviors and cognition," said Martin Sereno, psychology professor, cognitive neuroscientist and director of the SDSU MRI Imaging Center. "It has expanded so much that the folding patterns are very complex."

[Continues . . .]

The paper is open access:

"The human cerebellum has almost 80% of the surface area of the neocortex" | Proceedings of the National Academy of Sciences

QuoteAbstract:

The surface of the human cerebellar cortex is much more tightly folded than the cerebral cortex. It was computationally reconstructed for the first time to the level of all individual folia from multicontrast high-resolution postmortem MRI scans. Its total shrinkage-corrected surface area (1,590 cm2) was larger than expected or previously reported, equal to 78% of the total surface area of the human neocortex. The unfolded and flattened surface comprised a narrow strip 10 cm wide but almost 1 m long. By applying the same methods to the neocortex and cerebellum of the macaque monkey, we found that its cerebellum was relatively much smaller, approximately 33% of the total surface area of its neocortex. This suggests a prominent role for the cerebellum in the evolution of distinctively human behaviors and cognition.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


xSilverPhinx

Quote from: Recusant on August 05, 2020, 09:07:40 PM
A new MRI study indicates that the surface area of the human cerebellum is greater than had previously been thought.



"'Little brain' or cerebellum not so little after all" | ScienceDaily

Quote

Cerebellum highlighted in illustration of brain. Image credit: © decade3d / stock.adobe.com




When we say someone has a quick mind, it may be in part thanks to our expanded cerebellum that distinguishes human brains from those of macaque monkeys, for example.

Sometimes referred to by its Latin translation as the '"little brain"', the cerebellum is located close to the brainstem and sits under the cortex in the hindbrain. New research at San Diego State University, however, calls the "little" terminology into question.

The cerebellum plays a versatile role, contributing to our five senses as well as pain, movements, thought, and emotion.

It's essentially a flat sheet with the thickness of a crepe, crinkled into hundreds of folds to make it fit into a compact volume about one-eighth the volume of the cerebral cortex. For this reason, the surface area of the cerebellum was thought to be considerably smaller than that of the cerebral cortex.

By using an ultra-high-field 9.4 Tesla MRI machine to scan the brain and custom software to process the resulting images, an SDSU neuroimaging expert discovered the tightly packed folds actually contain a surface area equal to 80% of the cerebral cortex's surface area. In comparison, the macaque's cerebellum is about 30% the size of its cortex.

"The fact that it has such a large surface area speaks to the evolution of distinctively human behaviors and cognition," said Martin Sereno, psychology professor, cognitive neuroscientist and director of the SDSU MRI Imaging Center. "It has expanded so much that the folding patterns are very complex."

[Continues . . .]

The paper is open access:

"The human cerebellum has almost 80% of the surface area of the neocortex" | Proceedings of the National Academy of Sciences

QuoteAbstract:

The surface of the human cerebellar cortex is much more tightly folded than the cerebral cortex. It was computationally reconstructed for the first time to the level of all individual folia from multicontrast high-resolution postmortem MRI scans. Its total shrinkage-corrected surface area (1,590 cm2) was larger than expected or previously reported, equal to 78% of the total surface area of the human neocortex. The unfolded and flattened surface comprised a narrow strip 10 cm wide but almost 1 m long. By applying the same methods to the neocortex and cerebellum of the macaque monkey, we found that its cerebellum was relatively much smaller, approximately 33% of the total surface area of its neocortex. This suggests a prominent role for the cerebellum in the evolution of distinctively human behaviors and cognition.

That's so cool.  8)
I am what survives if it's slain - Zack Hemsey


xSilverPhinx

Ever see a Purkinje cell? This is a Purkinje cell:



Looks like a little tree. In fact, the word dendrites, which are those ramified projections, comes from the word déndron, which is ancient Greek for 'tree'.



 
I am what survives if it's slain - Zack Hemsey


Randy

Those pictures of the cells are pretty, Silver.
"Maybe it's just a bunch of stuff that happens." -- Homer Simpson
"Some people focus on the destination. Atheists focus on the journey." -- Barry Goldberg

Recusant

Quote from: xSilverPhinx on August 21, 2020, 06:45:56 PM
Ever see a Purkinje cell? This is a Purkinje cell:



Looks like a little tree. In fact, the word dendrites, which are those ramified projections, comes from the word déndron, which is ancient Greek for 'tree'.




Dig the images. I've always had a soft spot for the black/electric chartreuse color combination.  :smokin cool:

Maybe it's me, but I'm going to say that the "Structure" section of the Wikipedia article is sad. I'll cite its final sentence, but the whole thing suffers from the same disability:

QuotePurkinje cells send inhibitory projections to the deep cerebellar nuclei, and constitute the sole output of all motor coordination in the cerebellar cortex.

How do you parse that? I get "purkinje cells ... constitute the sole output of motor coordination in the cerebellar cortex."

Cells are the output of motor coordination? Not being an expert, I might guess as to the actual meaning: "Purkinje cells send inhibitory projections to the deep cerebellar nuclei. These inhibitory projections constitute the sole output of all motor coordination in the cerebellar cortex."

Still dense and uninformative to a lay reader, even if my edit presents an accurate version of the idea. What are "inhibitory projections" for instance? The section reads to me like the output of somebody who knows exactly what they're talking about (being generous here, because I didn't understand it) but is not able to present it effectively.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


xSilverPhinx

Quote from: Recusant on August 22, 2020, 12:30:28 AM
Dig the images. I've always had a soft spot for the black/electric chartreuse color combination.  :smokin cool:

Maybe it's me, but I'm going to say that the "Structure" section of the Wikipedia article is sad. I'll cite its final sentence, but the whole thing suffers from the same disability:

QuotePurkinje cells send inhibitory projections to the deep cerebellar nuclei, and constitute the sole output of all motor coordination in the cerebellar cortex.

How do you parse that? I get "purkinje cells ... constitute the sole output of motor coordination in the cerebellar cortex."

Cells are the output of motor coordination? Not being an expert, I might guess as to the actual meaning: "Purkinje cells send inhibitory projections to the deep cerebellar nuclei. These inhibitory projections constitute the sole output of all motor coordination in the cerebellar cortex."

Still dense and uninformative to a lay reader, even if my edit presents an accurate version of the idea. What are "inhibitory projections" for instance? The section reads to me like the output of somebody who knows exactly what they're talking about (being generous here, because I didn't understand it) but is not able to present it effectively.

Hmm...good question. :notsure: To be honest I found it a bit dense as well. As for 'inhibitory projections', those would be due to the fact that Purkinje cells inhibit the firing of other neurons. They are GABAergic neurons (secrete GABA), with GABA being the main inhibitory neurotransmitter in the SNC. Thus, they are important in fine motor tuning.

But yeah, that wiki article could do with some clearer writing.
I am what survives if it's slain - Zack Hemsey


Recusant

Sorry but you are not allowed to view spoiler contents.
Sorry, xSilverPhinx, I won't impose upon your good nature by carrying on down this rabbit hole.  :snicker1:

Wikipedia is just reminding me that if I want to learn more about this I need to find better sources.

That's just one sentence, but as I said before I think pretty much everything in that section fails along the same lines.
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


xSilverPhinx

Quote from: Recusant on August 22, 2020, 12:54:58 AM
Sorry but you are not allowed to view spoiler contents.
Sorry, xSilverPhinx, I won't impose upon your good nature by carrying on down this rabbit hole.  :snicker1:

Wikipedia is just reminding me that if I want to learn more about this I need to find better sources.

That's just one sentence, but as I said before I think pretty much everything in that section fails along the same lines.

Heheh! When you say 'projected', do you mean like shot out of the neuron or something? :snicker: I think 'secreted' is a better word in this sense. :P When they're talking about GABAergic projections, it's way more likely they mean the GABAergic neuron's projections. 

Rabbit hole? Where? :popcorn:

:grin:

ETA: If you haven't heard of it already, you might want to try Scholarpedia. They have more comprehensive articles.
I am what survives if it's slain - Zack Hemsey


Recusant

#189
Thank you for the clarification! Wikipedia can be cool, but some of the more obscure articles are ridiculous. In my electronic travels I came across the article about Serikornis, a fossil species that definitely appears to be in the evolution from dinosaur to bird. In the article's "Description" section, the following sentence could be found:

QuoteSymmetrical, balloon-free remorces are attached along the forearms and elongated feathers of the hind limbs extend to the toes, suggesting that the remiges of the hind legs had evolved in the maniraptorans residing on the ground before being co-opted into an avian flying lifestyle or a gliding arboreal veil.

"Balloon-free"??? What the hell are "remorces"? "A gliding arboreal veil" sounds picturesque, but really I think I'd have to have some chemical assistance to make sense of it. That might be a pleasing experience and there's a chance I'd gain some knowledge along the way, but not about Serikornis;)

I found the source and re-wrote the sentence.

Now that I re-read the section I see that further work is needed. As far as I've been able to determine, there is no such thing as a "camelles system." There is a French word "camelle," but that refers to a pile of salt, presumably part of the process of harvesting salt from a salt marsh. By the time anybody reads this, the "camelles system" will have gone the way of the gliding arboreal veil, though it will always be there in the history of the article.

My hypothesis is that the original author of the section used voice recognition software to write it, and didn't bother to edit the result.

I'm still working on the textbooks I downloaded from your link months ago, but will try to remember Scholarpedia in future, thank you.  :cheers:
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


Recusant

Elon Musk is worried about AI, so he's got his people working on cyborgs. Not that the term is used in the article, of course. Apparently he's looking for new talent to contribute to the project.

"Neuralink: Elon Musk unveils pig with chip in its brain" | BBC

QuoteElon Musk has unveiled a pig called Gertrude with a coin-sized computer chip in her brain to demonstrate his ambitious plans to create a working brain-to-machine interface.

"It's kind of like a Fitbit in your skull with tiny wires," the billionaire entrepreneur said on a webcast.

His start-up Neuralink applied to launch human trials last year.

The interface could allow people with neurological conditions to control phones or computers with their mind.

Mr Musk argues such chips could eventually be used to help cure conditions such as dementia, Parkinson's disease and spinal cord injuries.

But the long-term ambition is to usher in an age of what Mr Musk calls "superhuman cognition", in part to combat artificial intelligence so powerful he says it could destroy the human race.

[Continues . . .]
"Religion is fundamentally opposed to everything I hold in veneration — courage, clear thinking, honesty, fairness, and above all, love of the truth."
— H. L. Mencken


No one

Ear worms, where do they come from?

xSilverPhinx

Quote from: No one on August 30, 2020, 12:29:01 AM
Ear worms, where do they come from?

Sorry, didn't see this.  :P

Good question. I don't know, but it's possible earworms are, among other things, triggered memories. When you come across a word, image,  sound or other sensory stimulus that is somehow associated with a tune in your memories, that particular ensemble of neurons that support the musical memory will activate and you will experience the memory of the tune.   

For instance, let's say you're listening to Tony Igy's Astronomia while opening a can of peas. It's possible you associate the smell of canned peas with the song, and the next time you experience that particular smell there's a good chance you evoke the memory of freakin' Astronomia::)

If the song has lyrics, then it could be a word or a subjective feeling of a concept (depending on how you think) that evokes the tune.

There seems to be a degree of obsessive tendencies in the frequency in which someone has earworms. I don't think you need to have full-blown OCD to have that problem, just a mild condition will do.  ;D 
I am what survives if it's slain - Zack Hemsey


xSilverPhinx

This is interesting:

Acetaminophen Alters Perception of Risk

Quote"Acetaminophen seems to make people feel less negative emotion when they consider risky activities — they just don't feel as scared," said Baldwin Way, co-author of the study and associate professor of psychology at The Ohio State University.
I am what survives if it's slain - Zack Hemsey


Randy

That is interesting, Silver. I keep quite a bit of acetaminophen in my drawer. From time to time I get headaches and I don't know the cause. It's been a couple of weeks since I've taken some.

But I wouldn't be thinking of doing something dangerous anyway.
"Maybe it's just a bunch of stuff that happens." -- Homer Simpson
"Some people focus on the destination. Atheists focus on the journey." -- Barry Goldberg