[HN Gopher] First images of cerebrospinal fluid in the brain dur...
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First images of cerebrospinal fluid in the brain during sleep
(2019)
Author : robg
Score : 245 points
Date : 2022-02-05 15:49 UTC (7 hours ago)
(HTM) web link (www.bu.edu)
(TXT) w3m dump (www.bu.edu)
| jonnycomputer wrote:
| This is very cool. Should be tagged 2019 though.
|
| Would be interesting to see if individual differences in this
| process is correlated with psychiatric disorders at all.
| ilrwbwrkhv wrote:
| Wonder if transcendental meditation achieves something similar.
| toss1 wrote:
| Very cool. I'd be very curious see if there are similar effects
| from basic meditation and/or from very advanced meditation in
| yogic or Buddhist traditions.
| erikerikson wrote:
| This is curious. During my research into neutral networks we
| depended on a neuroscience result that found waves of trophic
| factor (i.e. the stuff used to build up neurons [i.e. learn])
| travel in cascading waves from the core of the brain to the
| periphery. By adding a sense of location and a learning term
| contingent on the factor we saw learning (xor) prohibited by
| Minsky's result (not really prohibited because we changed the
| model).
|
| The take away was that our models of ANNs benefit from
| considering more that just neural signaling (i.e. solution
| contents and fluid dynamics). Is anyone aware of modern work
| expanding on that front?
| loceng wrote:
| My own evolving hypothesis is that pressure(s) in the body is a
| very important "setting," as well as the effects of natural
| Faraday cages that occur throughout the body/brain and at
| different layers.
|
| To note, I'm really curious how a no-to-low inflammatory vs.
| high inflammatory diet would impact this visual; likewise
| seeing differences between short-term and long-term, and things
| like before and after if switching between/cleaning up a diet
| or going from low inflammation to high inflammation over 1-5-10
| years.
| l33t2328 wrote:
| What was Minsky's result?
| erikerikson wrote:
| 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...
| erikerikson wrote:
| 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 because no explicit later exists
| but in another sense the modulation provided a transient
| layers since the learning term caused different parts of
| the network to learn at different times out of sync with
| one another.
| whimsicalism wrote:
| Was this research conducted prior to 2005?
|
| I find the whole xor result to be pretty irrelevant, which I
| think is representative of the field writ large.
|
| > Is anyone aware of modern work expanding on that front?
|
| I am curious about this as well, as well as the general state
| of biological inspiration in the field. My impression was that
| biological analogy had largely been pretty much completely
| moved away from, except as someplace to take inspiration from
| in terms of what optimization can achieve.
| erikerikson wrote:
| Yes, 2004 but now I'm curious why you ask. ?
| whimsicalism wrote:
| just because 90s-early 00s is the time period where I
| perceive this style of research to have been at its peak,
| so I was curious if my assumptions were correct
| chaxor wrote:
| It _was_ moved away from, but in recent years it 's been
| picked up again, with growing intensity. Just look at
| deepmind for example, which has been publishing with
| neuroscientist wet labs. Two papers come to mind - one
| showing the "prefrontal cortex as meta reinforcement
| learning", and another about distributional temporal
| difference learning wherein specific neurons were examined.
| suifbwish wrote:
| That's pretty cool. What is interesting about your studies is
| you have the opportunity to apply modified fluid dynamics
| principles to a neural environment. You might also try an
| approach of allowing the network to have a refresh cycle where
| you add byproducts that accumulate as a result of operation and
| must be cleansed during a separate cycle. In this other cycle
| you could apply other NN operations such as GAN ect to allow
| the network to "dream" and create/remove various pathways. This
| is probably beyond the scope of your work but it seems like
| pretty cool opportunities for experimentation since there are
| probably only a few thousand people on the planet that fully
| understand all of these concepts.
| robg wrote:
| Where AI and neural networks still have so much to learn from
| actual intelligence. Seems like _the_ technical and
| computational problem set for this century, where a greater
| understanding of brains will branch out more broadly.
| dtgriscom wrote:
| Cool video, but it would be much cooler if there was some idea of
| the timescale (i.e. how often do these waves occur?). I doubt
| that it's shown real-time; perhaps 10x or 100x?
| dtgriscom wrote:
| And, I've been searching for the actual study/paper, but with
| no success. 'Twould be good for the BU press blurb to link to
| it...
| dtgriscom wrote:
| Found it, I think:
| https://www.science.org/doi/abs/10.1126/science.aax5440
|
| But, it isn't open-access...
| icegreentea2 wrote:
| Pre-print:
| https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309589/
|
| Final (need $$):
| https://www.science.org/doi/10.1126/science.aax5440
| odnes wrote:
| The pre-print say the pulses occur with a frequency of ~0.05 Hz
| (once every 20s). So at a guess the video is sped up 20x.
| turnerc wrote:
| Open-access link:
| https://www.science.org/doi/full/10.1126/science.aax5440
| Registration is required.
| imperfect_light wrote:
| Interesting but is there any comparison with CSF while awake? Is
| there more CSF movement while sleeping?
| bjackman wrote:
| Re falling asleep during MRI - I was a subject in a study where
| for about an hour you had to lie in a machine and repeatedly
| indicate which of two pictures depicted a larger object. They
| said subjects falling asleep was a big problem! I find sleeping
| very difficult and even I was feeling extremely drowsy after 45
| mins of lying down and establishing "elephants are bigger than
| mice. Houses are bigger than shoes. Trees are bigger than
| flowers. Cars are bigger than dogs etc etc etc"
| Mezzie wrote:
| 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.
| MattGaiser wrote:
| How is your aircraft sleeping?
| Mezzie wrote:
| Amazing provided people shut up. I'm also 5'3" so I'm
| comfortable in airline seats.
| datameta wrote:
| 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.
| Mezzie wrote:
| I never understood opting for music. MRIs are so loud; the
| last thing I want on top of it is competing noise. How is
| that not sheer cacophony?
| datameta wrote:
| MRIs are stunningly loud indeed. The music would distract
| me from the noise patterns which other than being
| interesting to me don't keep me from napping in what to
| me is a cozy tunnel (whereas the music might).
| lrvick wrote:
| I find loud screamo music the most soothing and
| compliments background machinery well.
| mrandish wrote:
| I have to get an MRI roughly once a year to monitor a benign
| cyst and ensure it doesn't start to grow. My first experiences
| with MRI were okay. Certainly not pleasant but not an issue. I
| can't even imagine actually falling asleep inside an MRI
| though.
|
| Last year I actually went the other direction. I was switched
| to a somewhat older MRI machine in a different building,
| apparently somehow "due to COVID." I thought the tunnel in the
| usual MRI machine was tight but this older model was even
| smaller. Also, due to COVID they insisted that I have on an N95
| mask inside the machine, underneath the 'Magneto-like' helmet
| used to hold head position. I was able to complete the lengthy
| session but these changes were enough to trigger what I assume
| was some claustrophobia and it was _not_ fun. It required
| maximum mental effort just to make it to the end.
|
| I just got the call from my doc to schedule this year's scan
| and apparently the same requirements are still in place
| although they are "hoping things get back to normal soon." I
| mentioned how challenging last year's scan was and he suggested
| we just defer it until Summer. I felt conflicted about this as
| I really don't want to be postponing diagnostics but damn, last
| year was pretty awful, so I went for the reschedule.
| Robotbeat wrote:
| Am I the only one for whom the video isn't loading? On iPhone.
| Very frustrating.
|
| (Of course, requesting the Desktop version does jacks***---only
| the mobile page is displayed, as expected...)
| ghostly_s wrote:
| It's loading for me on iphone, but I'm not seeing any blue
| waves? Just red waves in increasing frequency. Very confused.
| euroderf wrote:
| Think of sleep as a powerwash for the sticky trash-covered movie
| theater floor that is your brain. When the big screen goes dark,
| break out the hoses and scrub away all that accumulated crud.
| mensetmanusman wrote:
| Sensory input goes dark, but the brain is quite active creating
| simulated spaces and threat response environments.
| bitL wrote:
| I had some crazy dream once when some unexpected home
| visitors in black suits suddenly started shooting at me and I
| did an all-out-effort to escape them, running/jumping like
| crazy. While I ran as fast as I could (it really felt that
| way), I heard some dampened noise as if somebody was
| screaming. Soon I somehow escaped and was suddenly waking up.
| That was when I realized it was me screaming while dreaming
| about escaping the attack. My heartbeat was over 180 as well.
| I am wondering what was my brain preparing me for.
| buovjaga wrote:
| Publications from the lab:
| https://www.lewisneurolab.org/publications
| seesawtron wrote:
| Funny that the lab provides an "open-access link" to this 2019
| paper which turns out to be the opposite.
| samstave wrote:
| 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.
| daanlo wrote:
| What helped me the most against my insomnia is simply accepting
| it. I just stopped fighting to try to sleep. It didn't help
| immediately, but at least the time that I wasn't falling asleep
| was less painful. Over time (several months/years) my insomnia
| eventually went away.
|
| Years later I listened to an audio book by The psychologist
| Viktor Frankl, that also helped me relax about the topic.
|
| And of course jogging (without music) or something similar that
| essentially switches off your brain during day time.
| samstave wrote:
| Wow - So a few comments on what you beautifully wrote for me:
|
| * I attempt to accept it and Breathe - (Some WIM HOF and I
| just received the book "BREATH" [0] <-- _technically_ i just
| received via grabbing from my book-shelf _after_ having
| bought it 6-months ago, without ever picking it up....
|
| :-( --> :-))
|
| [0] https://www.mrjamesnestor.com/
|
| ---
|
| I used to run ~2001+ 15 miles a day. But in 5 mile blocks
| (this was the Internet Turn Down of 2001 (aside: had a party
| with 75 guests, 10 had tech jobs in middle of Turndown)
|
| I would run 5 mile morning loop, lunch loop, dinner loop.
|
| I havent been running - have been riding 29"er - and Aug/21 I
| rode 26 miles a day for 30 days straight, + more but I only
| tracked 800 miles on my Strava... There were so many days I
| forgot to turn on strava, until 8/1 and turned it on for a
| consistent 30 days...
| Mazgas wrote:
| I had a friend who had a surgery to unblock the cerebral fluid
| paths. Not sure if "shunt" is a technical name for it, but that's
| what he said.
|
| Also, he said he had insomnia before it. Really cool to see it.
| Internal plumbing of a human body.
| exdsq wrote:
| Oh cool, my wife's in the lab of one of the coauthors. It seems
| like brain imaging is a really really small world.
| nomadpenguin wrote:
| I recently worked on a project involving segmenting clinical CT
| scans. Almost every python package for working with CTs was
| written by the same guy.
| sva_ wrote:
| (October 2019)
| dang wrote:
| Year added above. Thanks!
| hbarka wrote:
| What is the ideal sleeping position to maximize brain wash? Is it
| back, side, slightly inclined? Fluids theory would surely dictate
| how we can better align our body to encourage this. Intuition
| says our neck torsion must be instrumental to a good flow.
| nxmnxm99 wrote:
| Of all the worldly anxieties dominating modern existence I
| cannot imagine why you would want to add another one
| hutzlibu wrote:
| Probably because THIS is finally the magic bullet, that not
| knowing it, was holding me back for years.
| tazjin wrote:
| You don't know what effect this has. Why do you want to
| maximise it?
| guerrilla wrote:
| Only if they didn't read the article, which explains "Earlier
| studies have suggested that CSF flow and slow wave activity
| both help flush toxic, memory-impairing proteins from the
| brain." and more.
| nlitened wrote:
| Studies may have suggested something, does not mean they
| have proven that same thing. Also, "toxic memory impairing
| proteins" is some kind of hand-wavy journalistic clickbait
| and not actual science.
| guerrilla wrote:
| > proven
|
| Studies don't "prove" things.
|
| "toxic memory impairing proteins" is literally what they
| are. They impair memory and when they accumulate, they
| are toxic. There's nothing hand-wavy about it. These
| words have meaning.
| tiborsaas wrote:
| Wake up in the middle of the night, shake your head violently
| and turn to the other side. That probably will do it.
| staticassertion wrote:
| If I'm lucky, constant tossing and turning.
| [deleted]
| hbarka wrote:
| 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.
| ciphol wrote:
| Head up or head down?
| wrycoder wrote:
| In some cultures, it was traditional to use the skull of
| your enemy as a pillow.
| MithrilTuxedo wrote:
| I assume you would want to rotate.
| hammock wrote:
| It would really just take sleeping on your back with head to
| the left, and head to the right. This approach works for
| sinus drainage as well.
|
| So many people cannot/do not sleep on their back, though.
| bitL wrote:
| Centrifugal bed from IKEA.
| mawadev wrote:
| I will sleep in a washing machine from now on
| wincy wrote:
| Very cool. My daughter has a brain shunt due to complications of
| spina bifida and so we're thinking of cerebrospinal fluid on a
| regular basis. As a layman I guess there's a particular
| cerebrospinal fluid pressure you want, and that being too high or
| too low causes issues? Apparently the shunt just drains into her
| belly so I also found that interesting. Too high and she'll have
| terrible headaches and an "alien" head (sorry, don't mean offense
| by that but it's what I'm trying to avoid for my child) and I
| don't know what would happen with too little, maybe someone could
| tell me. Probably not good I'm assuming.
|
| I frequent some FB groups for parents of children with SB and am
| shocked at how large some people let their kids heads get without
| consulting with or complaining to a doctor.
| asia92 wrote:
| what exactly do you mean by alien head? not offended, just
| curious
| wincy wrote:
| I can't post the specific child's picture as it wasn't posted
| publicly and I wouldn't want to disrespect them, but here's
| some examples of less severe hydrocephalus you'll see often
| in spina bifida parenting groups [0] [1]. Often people don't
| comment on ones like that as everyone wants to get along but
| if it's left untreated it can eventually progress to be much
| more severe and cause debilitating headaches and mental
| retardation. Interestingly, in googling this apparently low
| pressure cerebrospinal fluid headaches are also a thing [2],
| so keeping just the right amount of cerebrospinal fluid
| draining is a must.
|
| [0] https://www.hydroassoc.org/people-view/wylie-6-months/
|
| [1] https://www.travelblog.org/Photos/253290
|
| [2] https://www.hopkinsmedicine.org/health/conditions-and-
| diseas...
| airstrike wrote:
| You can google "hydrocephalus", though I should warn the
| images can be a bit disturbing
| 1-6 wrote:
| At least in the US, early intervention allows doctors to
| recommend shunts so extreme cases of hydrocephalus can be
| avoided and head sizes normalize a bit as kids grow. The
| photos are usually from med textbooks and for teaching
| future doctors and usually demonstrating the extreme forms.
|
| Let's not say alien head. My biggest worry as a young dad
| was my child being called names because of his head
| circumference. He too was born with HC.
| sezna wrote:
| a physically large head, shaped similarly to a stereotypical
| alien head
| turnerc wrote:
| I believe they mean enlarging of the fontanelle as is typical
| in those with hydrocephalus.
| bobowzki wrote:
| I think it drains into the peritoneum but I'm not completely
| sure. There's a resistance on the shunt to maintain pressure.
| Too high will cause hydrocephalus with all sorts of
| complications. Too low will cause a massive headache short
| term, long term I'm not sure. I'm an anesthesiologist and
| frequently work with neurosurgeons.
| mensetmanusman wrote:
| The technical founder of this company is developing wireless
| monitors for this cerebrospinal fluid pressure:
|
| https://www.rhaeos.com/
|
| We got to hear him speak pre-pandemic, definitely cool tech.
| chriscross wrote:
| Too little CSF leads to the brain crushing itself under
| gravity. The brain is almost entirely lipids which contributes
| to its buoyancy in CSF. Take away too much CSF, nothing for it
| to float in. Too much CSF? The skull is a fixed volume (in
| adults) so the CSF compresses the brain tissue. In kids, the
| sutures or junctions between bones of the skull are still
| flexible. This allows for childbirth and normal rapid brain
| growth. It's easy to tell if there too much fluid around the
| brain in a newborn because their front soft spot (Fontanelle)
| will bulge or become firm. A bulging fontanelle also occurs
| with other pathologies like meningitis.
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