Brain may flush out toxins during sleep (2015) | Hacker News Reader

Brain may flush out toxins during sleep (2015)

qz.com

120 pointsprostoalex43 comments

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Related, there is the possibility that posture during sleep may impact the efficiency of the glymphatic system

Paper: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4524974/

Press release: http://sb.cc.stonybrook.edu/news/general/150804sleeping.php

Thanks for this. Tldr is sleeping on your side may be best for toxin draining.

It sure is if you're a mouse.

There's no human data at this point.

I don't see the word "toxin" anywhere on that page.

You're right. I guess the connection being reached for is "lymphatic transport" (title of paper) -> "waste transport" (synonymous) -> "toxin removal" (a very specific type of waste transport?)

The lymphatic system is specifically for removing toxins, so naturally it's function is implied

No, a toxin is a poison, usually produced for predation or defense. As Wikipedia correctly notes,

In the context of quack and alternative medicine the term "toxin" is used to refer to any substance supposed to cause ill health.

What the body produces and might need to eliminate is metabolic byproduct or waste, nothing to do with "toxins". The term used in this context makes me cringe.

what...? Do you not know any biology at all? Of course the lymphatic system is meant to eliminate toxins... Jeez, take some bio 101 before posting, you sound like a quack

They are taking issue with the term "toxin" - not the functionality of the lymphatic system. Their comment explicitly said `metabolic byproduct or waste, nothing to do with "toxins"`.

But of course it the lymphatic system eliminates toxins too. I mean, obviously this is all getting into semantics, but the lymphatic system helps to eliminate more than just metabolic products and waste, it will also help eliminate dead bacteria, heavy metals, etc, which could certainly be called toxins

Side sleeping has positive effects on airway maintenance, may help get in and stay in the deeper phases for some people with obstructive apnea.

Interesting. Personally I can't sleep without laying on my stomach

"warns that sleeping next to your smartphone—the one that emits 3G and 4G signals all night—affects your brain patterns, restructuring your brain cells and likely preventing you from allowing your brain to clean out waste material properly."

Does anyone have any kind of evidence/study of this kind of effects?

If you read the linked article, they find "...sensitivity to low-level radiation to a subtle degree...". Except they strapped cell phones to users' heads.

Given that cell-phone radiation falls off at a factor of 1/r^2, I would imagine the effects disappear very quickly as the cell phone gets further from your head. Also, the 2nd study used 10 sleep-deprived men. That's a pretty small sample size.

Thats what studies do, they use extremes to find clearer evidence.

10 is pretty small sample size by small sample size standards.

Yes it is, but that has nothing to do with what I said or what I replied to.

Emits signals all night is quite an exaggeration. Unless the phone is actively transmitting or receiving something, it only checks in with the network every once in a while.

I'm not sure about exact times in 3g/4g, but 2g (GSM at least) phones caused audible interference with poorly shielded audio equipment when they were transmitting. I recall an otherwise idle phone only checking in once an hour or so, though the interval was/is probably defined by the network, so that maybe different at different locations. Still, for power saving reasons, I expect an idle phone to just sit quiet most of the time.

> an otherwise idle phone only checking in once an hour or so

The phone network has to know which cell tower you're nearby in order to send a call to you. If you're driving, you could get far away from your original cell tower in one hour.

If your phone hasn't checked in for an hour and you've traveled a great distance in that hour, how does the phone network know where to send the incoming call for you?

I can think of only two solutions: Either your phone checks in much more frequently than once an hour, or the network tries pinging you on wider and wider concentric circles of cell towers in order to locate you. Which is it? (Or something else?)

The phone itself wakes up and listens for the base; if it finds it (and the ID matches) then it goes back to sleep. No need to transmit. If the ID doesn't match, it pings the new base to register and the network will inform the old base to drop that client. If it doesn't find the base at all it initiates a longer scan to find active bases on other frequencies. Once it finds the best one it has to re-negotiate and auth before the base will start accepting traffic on behalf of that client. Handoff bypasses the delays by having one base communicate to another to bypass the negotiations and the backhaul network automatically re-routes packets when this happens. The clients also get info about neighboring cells and towers which makes handoff easier and faster. As the baseband wakes up in its lowest power mode every minute or two it senses its connected base signal getting weaker while simultaneously one of its neighboring signals getting stronger and during one of these wake sessions it will elect to power up, transmit, and hand-off. Then it can go back into low-power monitoring mode until the next boundary. (This is an extremely abbreviated description of a complex process.)

The minimum ping time (let's say it is one hour) is just so the base can prune its client list.

When an SMS or call comes in the network doesn't broadcast that to all cells in the country. It knows where your device was last registered and sends it there even. If the base doesn't get an acknowledgement after a timeout period the SMS is dropped / the caller gets voicemail. If your device isn't near that location it should have handed-off on its own which means it is probably turned off or in an area with no signal.

As far as I know none of the current generation of cell systems bother to broadcast SMS, phone, or data packets to a wider area near your last known location.

Groups of cells are tagged with what is known as a "location area." The phone monitors a list of neighbor cells during its periodic wake ups (around 1-1.5 seconds) and reselects the strongest one. If the phone needs to reselect to a cell that is in a different location area, it sends a message to the network known as a "location area update." The network updates a database known as the HLR (home location register) that tracks the location area where the mobile last checked in. There is a policy called a "cell reselection hysteresis" that keeps it from ping-ponging between location areas if you are on the fringe of two.

The mobile also needs to send what are known as "periodic location area updates," to keep its entry up-to-date. Most networks I've seen have a 56 minute interval for that.

When the network needs to page a mobile, it sends the message to all cells in a location area.

I'm not certainly most phones are "otherwise idle" given push notifications, apps phoning home, etc. But, most of those devices are probably on wifi when their owners are at their homes asleep in their beds.

Phones turn off wifi whenever they can to save battery life. For example, Apple: "Notifications use Wi-Fi only when a cellular connection is unavailable." [1]

[1] https://support.apple.com/HT201925

I can send a text message to my phone and have it be received within a second or two, so my phone must be connecting with the cellular network at least once a second.

It wakes up around once a second to listen on the paging channel, but it doesn't transmit at that time.

It's funny how developers have completely lost the idea of real push messages, and ended up thinking that the client always have to initiate the connection.

Thankfully my cat sleeps on top of my head and shields from my mobile charging on the bedside table.

That's what your cat is programming you to think while it's on your head all night. You buy the expensive cat food now too, don't you...

He won't eat the cheap one. His food costs more than the tuna cans I eat.

This sounds like pseudo-science so I'd be extremely wary. Small study making bold claims based on an extremely subtle effect almost always turns out to be statistical noise or a flaw in the study.

Margaret Thatcher famously survived on 4 hours sleep a night, and later developed dementia. I wonder if any longitudinal studies have been done on this (I had a quick look and couldn't find any).

As a migraine sufferer I feel like I can confirm this, anecdotally. Often when I fight a migraine off midday it takes at least a 10 min nap to get back to somewhat normal feeling. I don't know how to describe what that nap can feel like. It feels a lot different than any other sort of sleep. Like the mental equivalent of standing on the top of a train that's descending down into a deep cavern and then back up to the light.

Walking (or other activity) promotes rapid movement of lymph out of the tissues, by several times the normal resting rate. It is powered by the muscle system. Anecdotally: After walking, I sleep more deeply (in a manner that I think has to do with moving lymph out of the brain). I suspect that moving lymph to clean other tissues in the body helps the brain move more lymph when it sleeps.

Any papers you can link to about this?

Study on muscle action and lymph flow that indicates this is well established in multiple studies and indicates 3-6 x faster clearance with activity, though I have seen higher numbers elsewhere and, to my surprise, cannot readily locate that info at the momemt:

http://onlinelibrary.wiley.com/doi/10.1111/j.1469-7793.1997....

I am unaware of any papers on the piece I described as anecdotal and my opinion. Though a quick Google gets me this piece that claims it is by an MD and, among other things, talks about exercise and brain health:

http://jonlieffmd.com/blog/the-five-secrets-of-brain-health

I for one would like to know if meditation would serve to flush toxins as well, and if so, to what extent.

I often struggle to get more than 6 hours of sleep, but have started doing TM a few weeks ago with two twenty minute sessions (not always getting both in..) - and am finding it helpful. This is knowing / having been told that meditation is not a substitute for sleep.

I have turned to meditation recently for those nights when I can’t sleep, and I feel it helps me. Nothing comparable to having slept well, of course, but it seems to ease my way forward during a few hours.

To be honest I’m not exactly sure if I should call it meditation. I just lie on the bed, or sit, eyes closed while I let my thoughts flow as freely as possible, getting to an quasi-dreaming state, where I experience images and sounds.

It’s the same thing I do when taking sleepless “naps”, with the difference of having a much more clear refreshing effect.

Sounds very unlikely, if someone interrupted your meditation would you feel groggy like interrupted sleep? I believe meditation is mostly psychological, while sleep is physiological.

That depends on the meditation - it's never quite the same, really varies a lot. Now, I've taken to doing a lunch time meditation in the tinted back seat of my car (secure carpark) and some times I've actually nodded off for a fraction of second or two - or who knows how long.

At any rate if I was disturbed between the 10 and 20 minute mark when I typically start to settle into it I'd feel a bit rattled. You're meant to spend a minute or two getting back, slowly stretching out and opening the eyes. Always feel a bit sleepy, but then also strangely refreshed.

As a programmer I do find slowing the "mind storm" rather beneficial. Definitely feeling less frazzled.

Possibly daydreaming/napping might achieve the same thing.

In fact, I think napping is possibly more useful than meditation in terms of compensating for lost sleep in general.

Well shame I'm sitting here reading HN at 5:30 while debugging computer problems

We briefly changed the URL to https://www.nih.gov/news-events/news-releases/brain-may-flus..., which this article points to, but changed it back because this article contains more background info. We kept the less baity title, though.

Yes, the old article was actually already posted here.

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