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Brains Sweep Themselves Clean of Toxins During Sleep (2013)

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Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#121

Post by randcraw »

inputcoffee wrote: post #59
bitexploder wrote: post #15

The actual research is quite interesting. Sleep disorders themselves are fascinating. There is evidence that TBI (traumatic brain injury) can cause lasting sleep cycle disruption. Perhaps sleep disruption and TBI is a much bigger factor in the lasting impact of TBI than previously thought. ( https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3482689/ ). Article review: This is pretty good science reporting, actually provid…

Are you sure scientists don't use the term? Consider: https://scholar.google.com/scholar?hl=en&q=toxins+brain&btnG... I don't have more information. I just typed that in based on your comment.

In biology, toxins are compounds that cause injury. The wording in the article implies that all waste products removed by sleep are toxic, which is unlikely. Many chemicals removed by sleep probably are not toxins, at least perhaps, not until they accumulate and form obstructions, like Alzheimer plaques.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#122

Post by randcraw »

bryondowd wrote: post #22
mabbo wrote: post #3

> The process is important because what's getting washed away during sleep are waste proteins that are toxic to brain cells, Nedergaard says. Evolution found a nice little optimum in sleep that works pretty well- use less energy during a time of the day that isn't a very efficient time to be awake while also cleaning out the brain. This could be interesting for future research. Could we find chemical means to remove…

There's an interesting concept. I wonder what the trade-off would be. How much efficiency would it cost to clean the brain continually rather than in a dedicated sleep cycle? Would it even be possible to process these toxins while maintaining consciousness? I'm sure there could be huge benefits for many modern lifestyles to trade heavily on reaction speed and/or lightly on IQ for 50% more waking hours. Or even 25% mo…

I think nature's solution to this kind of inefficiency arises by adopting a new social behavior rather than evolving a new DNA-based physical ability. It's easier and faster for a group of animals to appoint a guard to protect others during sleep than for the species to evolve a superior brain.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#123

Post by e40 »

Namrog84 wrote: post #66
e40 wrote: post #48

Earlier quoted context omitted.

I read somewhere in the last 10 years that dreams were practice for real life situations. After hearing that, when I awake in the middle of a dream, I always test that hypothesis, and sure enough, sometimes is quite plausible.

Most of my dreams involve a lot of supernatural events and scenarios that'd be quite unlikely in real life. Am I preparing for a day soon where magic, superpowers and other super natural events become real?

Perhaps you missed the "sometimes"...

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#124

Post by JimboOmega »

Puts wrote: post #112

Maybe looking for the reason we sleep is the wrong way to look at it? What if being asleep is the default state for any organism? Sleeping require much less energy. The only reason to be awake is to eat and reproduce. For any animal there is probably an optimal ratio between sleep and hunt/reproduction where sleep is the most favorable.

But sleeping makes you much more vulnerable to predation, and really doesn't save much more energy vs. quiet/restful wakefulness.

Just think of how disoriented you are when something wakes you up in the middle of night - that's a definite biological cost if that thing is something threatening to you.

And of course, never mind creatures that have gone as far as the 50/50 brain adaptation (IE Dolphins), they simply have to be at least partially awake all the time.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#125

Post by stevenh »

e40 wrote: post #48
Overtonwindow wrote: post #5

Random thought: Could dreams be a result of the processing of toxins? In the same way some "toxins" cause us to hallucinate etc. so too could these toxins, as a side affect of processing?

I read somewhere in the last 10 years that dreams were practice for real life situations. After hearing that, when I awake in the middle of a dream, I always test that hypothesis, and sure enough, sometimes is quite plausible.

This reminds me of how they used GTA V to train driverless cars.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#126

Post by smallgovt »

Puts wrote: post #112

Maybe looking for the reason we sleep is the wrong way to look at it? What if being asleep is the default state for any organism? Sleeping require much less energy. The only reason to be awake is to eat and reproduce. For any animal there is probably an optimal ratio between sleep and hunt/reproduction where sleep is the most favorable.

This strikes me as the type of comment that sounds artificially 'deep' but has no constructive or logical basis. What does 'default state' even mean in this context? The fact is we naturally sleep sometimes and we're awake at other times. If you're suggesting there's no reason for sleep other than conserving energy, that's patently false.

The (assumed) primary motive here is to find a way to sleep less. We already have ways to force wakefulness. We now need to find ways to mitigate negative side effects hence the research on various health functions sleep contributes towards.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#127

Post by asdA3asdas23 »

d8421l01vv4r wrote: post #85
Overtonwindow wrote: post #5

Random thought: Could dreams be a result of the processing of toxins? In the same way some "toxins" cause us to hallucinate etc. so too could these toxins, as a side affect of processing?

If dreams only were the result of some cleanup process (i.e. just arbitrary neurons firing), I imagine they would be a lot less coherent and all events would be (stochastically) independent. While dreams usually don't much make a huge lot of sense, they are sometimes quite realistic and "past" events seem to influence "later" events.

Interesting. If the cleaning process itself depended on firing of the neurons during the day (whatever happened that day) then activating to purge these same neurons could somehow appear to have some meaning where the activations would in some way be tied to the events triggered during the day. So, I guess in this sense dreams could be a cleanup without being random, but based on the daily usage (of course this is just an exercise in speculation :))

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#128

Post by forgotpwagain »

zip1234 wrote: post #50
mabbo wrote: post #3

> The process is important because what's getting washed away during sleep are waste proteins that are toxic to brain cells, Nedergaard says. Evolution found a nice little optimum in sleep that works pretty well- use less energy during a time of the day that isn't a very efficient time to be awake while also cleaning out the brain. This could be interesting for future research. Could we find chemical means to remove…

Or maybe some sort of mechanical pumping system? If it takes too much energy away from the brain to both remain awake and clear those proteins, a mechanical pump that is powered externally could solve that energy problem. (I'm only half joking--we already have mechanical means of replacing other biological functions such as a dialysis machine).

You might be interested in the normal physiology of cerebrospinal fluid [0] and the disease hydrocephalus [1] that occurs when there is a blockage in the normal flow path. As a treatment for hydrocephalus, bypass shunts (made of tubing) are installed inside the skull that create a relief path for the fluid to flow. Unfortunately, they often get clogged with cells due to various scar formation and immune reactions -- designing better shunts is an active area of biomaterials research, and it's quite possible that an external pump could be an upgrade (though we first have to show that it has benefit...).

[0]: https://en.wikipedia.org/wiki/Cerebrospinal_fluid

[1]: https://en.wikipedia.org/wiki/Hydrocephalus

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#129

Post by Jipha »

che_shirecat wrote: post #92
Jipha wrote: post #79

Earlier quoted context omitted.

Sure, but not everyone is taking them to avoid sleep. Regular users primarily use them to boost productivity during the day, followed by normal sleep.

True, that could be one way of framing the whole "using adderall/modafinil for productivity" issue. What is a "regular user" though? Someone with ADHD taking adderall in the morning to boost the "executive function" of his/her brain during the day? (as someone with ADHD, adderall sedates my hyperactive brain as opposed to its intended effect, look up the stimulant paradox for more on this) Someone who takes adderall…

Someone who uses a few days a week (not necessarily daily) as opposed to, say, occasional all-nighters before an exam. For example, mrleinad's comment:

> I take modafinil on a daily basis each morning, and have a regular sleep pattern of 7-8 hours a night. It even helps with going to sleep earlier, because I feel depleted by 10 PM, so there's less incentive for me to stay up and waste time that I could use resting for the next day.

Re: Brains Sweep Themselves Clean of Toxins During Sleep (2013)

#130

Post by dbenhur »

Puts wrote: post #112

Maybe looking for the reason we sleep is the wrong way to look at it? What if being asleep is the default state for any organism? Sleeping require much less energy. The only reason to be awake is to eat and reproduce. For any animal there is probably an optimal ratio between sleep and hunt/reproduction where sleep is the most favorable.

My cats figured this out quite a while ago.
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