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First images of cerebrospinal fluid in the brain during sleep (2019)

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Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#101

Post by ad404b8a372f2b9 »

erikerikson wrote: post #54
erikerikson wrote: post #53

Earlier quoted context omitted.

This [0] is probably a reasonable overview though I didn't read it thoroughly, it was on the right track. Basically that Hopfield networks couldn't learn XOR. The significance is that it moved us away from biologically plausible networks and precipitated back propagation which was the dominant learning paradigm in neural networks and mostly remains so. [0] https://alan.do/minskys-and-or-theorem-a-single-perceptron-s.…

The problem with XOR is that you need a line with dimension N, where N is the number of distinct inputs to the XOR, to separate true from false in the truth space. What I demonstrated was up to 6 dimensional XOR functions being learned in Hopfield networks using Hebbian learning with an additional learning term. I ran a "wave of learning" over the network modifying that terms. In a sense it is a layer free network be…

Could you share a link to your work? I'd love to read more about it.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#102

Post by journey_16162 »

datameta wrote: post #13
Mezzie wrote: post #10

Earlier quoted context omitted.

I get an MRI once a year and I frequently fall asleep because nothing puts me to sleep like mechanical white noise. It's kind of a problem because I try to move or jerk awake, which ruins the MRI. My MRIs take forever. I feel terrible for the attendants.

I used to get a funny look when instead of a choice of music I opted for silence in the headphones during an MRI. Then I think I started to say it dismissively enough with conviction and got nonreactions.

I'm not sure what's the problem. I have done MRI twice in the last year, I always told I don't want music and I don't see how someone would find it weird. I don't want to damage my ears - the music was super loud, and if they turned the volume down I would probably hear the noise anyway - and what if the music sucks? And I have to lay still listening to it, now that would be torture. The white noise is quite relaxing actually - and also funny, sometimes it feels like a word repeating over and over.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#103

Post by dmix »

ciphol wrote: post #55
hbarka wrote: post #32

Earlier quoted context omitted.

A few years ago, before Covid era (BC :), I did a tour of medieval castles in Europe and one observation that stuck in my memory was that the beds used by the royalty were constructed with an inclined position. I’m really curious how prevalent this was and if it was the preferred luxury style of the rich. In parts of Asia hard pillows (reeds/woven) were preferred over down.

Head up or head down?

Head up, like leaned back sitting.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#104

Post by treeman79 »

mitjam wrote: post #99
treeman79 wrote: post #75

Earlier quoted context omitted.

Had a spinal leak after a spinal tap. So too little fluid. It’s a very unique pain. Severe pain at top of head unless laying flat. I spent an entire week laying flat on a couch with a happy cat sitting on my chest. Initial treatment was an IV of caffeine. Then they they had to patch the hole.

Had the same also after a tap, went away after 5 months without a patch. Only things that helped was laying flat and coffein (less so than laying flat). A hard part of it was thinking it might never go away. Doctors told me to wait 6 months before trying a patch and they said it only works sometimes.

Ouch. Mine offered the next day. I waited a week before going back and getting one.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#105

Post by erikerikson »

ad404b8a372f2b9 wrote: post #101
erikerikson wrote: post #54

Earlier quoted context omitted.

The problem with XOR is that you need a line with dimension N, where N is the number of distinct inputs to the XOR, to separate true from false in the truth space. What I demonstrated was up to 6 dimensional XOR functions being learned in Hopfield networks using Hebbian learning with an additional learning term. I ran a "wave of learning" over the network modifying that terms. In a sense it is a layer free network be…

Could you share a link to your work? I'd love to read more about it.

It's rather dated but my dissertation is saved for posterity [0] and includes references and old Octave code.

[0] https://drive.google.com/file/d/1R4mS_4vzf5mycQez76O_mmpQDpT...

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#106

Post by jac241 »

sizzle wrote: post #91
jac241 wrote: post #82

Earlier quoted context omitted.

They tunnel it in the subq until the abdomen then they make a tiny incision in the peritoneum and depending on the neurosurgeon may have general surgery take a look laparoscopically to make sure there’s CSF flow then use the grasper to try to toss it in the right pericolic gutter over the liver.

How do they avoid bacteria from going up a shunt to the brain?

There’s generally no bacteria outside of the food tube though it certainly could happen the way you describe if there happened to be.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#107

Post by jac241 »

serf wrote: post #94
sizzle wrote: post #91

Earlier quoted context omitted.

How do they avoid bacteria from going up a shunt to the brain?

I thought that was an interesting question as a layman. I found this, which I thought was an interesting read. [0] [0]: https://www.sciencedirect.com/topics/medicine-and-dentistry/...

Yeah sterile technique has to be meticulous in shunt cases. There’s evidence that the number of people scrubbed into the case influences the shunt infection rate so students like me occasionally would not be permitted to scrub.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#108

Post by rajnathani »

> One explanation may be that when the neurons shut off, they don’t require as much oxygen, so blood leaves the area. As the blood leaves, pressure in the brain drops, and CSF quickly flows in to maintain pressure at a safe level.

If this theory about the blood leaving the brain due to the neurons needing less of it during sleep is true, then possibly that could be a supporting argument for why being more relaxed (i.e less stressed) before sleep is helpful for better sleep. My explanation for the hypothesis in the previous sentence is that the neurons due to being more worked out from being stressed would require the oxygenated blood to replenish them and thus the CSF would not naturally be able to seep in early while in bed for sleep.

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#109

Post by tsol »

treeman79 wrote: post #90
tsol wrote: post #88

Earlier quoted context omitted.

I've heard not having enough CSF is supposed to be one of the most painful headaches there are. How bad was it?

Fine if I was flat. A step below severe kidney stone otherwise. So not quite suicidal, but close. It was only tolerable Because I could lay flat and the pain would quickly resolve. If I laid flat for three or four hours I could stand up for about five minutes before the symptoms hit again. Not sure how strong the leak was. I suppose it could have been worse.

Interesting. Fascinating how you can go a lifetime without noticing CSF but one thing goes wrong and suddenly you can't even stand up. Good to hear you got better

Re: First images of cerebrospinal fluid in the brain during sleep (2019)

#110

Post by [deleted] »

samstave wrote: post #63

This really scares the shit out of me, because I have chronic insomnia, and I am aware of the effect of sleep on not just how my brain feels - but also my vision and eye-lids (being SUPER heavy even when my mind is racing....) I know how important sleep is to brain function, clearly... And it causes ADDITIONAL anxiety, snowballing into more insomnia... Fucking sucks.

[deleted]
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