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What is the real reason we sleep?

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Re: What is the real reason we sleep?

#51

Post by ctolsen »

narsil wrote: post #25

I took Matt Walker's class on sleep at UC Berkeley (Psych 133) and it was fascinating. Short-term effects of a lack of sleep are easily observable, and I'm sure we can all relate from personal experience. However, long-term effects of sleep deprivation are harder to determine. One of the few known correlations appears to be that people who are susceptible to psychiatric disorders such as schizophrenia are more likely…

This is an interesting one. I have sleep apnea, the result of which is basically chronic sleep deprivation even though you spend lots of time in bed. I struggled with all sorts of depressive symptoms (depression, anxiety, panic attacks) for years before getting a diagnosis, and 90% of the symptoms vanished overnight after treatment.

Re: What is the real reason we sleep?

#52

Post by tremon »

Majestic121 wrote: post #28
KannO wrote: post #26

Earlier quoted context omitted.

We can't all be plants and fungus.

Why? I think it is possible for life to evolve on a planet with only plants and fungus. Plants have been pretty successful down here on Earth, and I think most of them don't need animals for their survival (except flowers?).

I think it is possible for life to evolve on a planet with only plants and fungus.

That's kinda circular, given that plants and fungi are examples of evolved life :)

You are correct that plants don't strictly need help with pollination (they simply release their spores to the wind/current and hope they land on a receptive partner), however the odds of a succesful pollination decrease sharply as the number of competing plants in an area increase.

In my (uneducated) view, in a scenario where all life is stationary (rooted to the ground, hur hur), you are much more likely to find monocultures -- where most plants can interbreed -- or more species using asexual reproduction.

Re: What is the real reason we sleep?

#53

Post by ctolsen »

AznHisoka wrote: post #46
Hydraulix989 wrote: post #22

Earlier quoted context omitted.

It's mostly sleep deprivation though. I graduated with a 3.7 from a top 5 school in CS after I was treated. My apnea was SEVERE before treatment: 30 apneas per hour. I doubt I had any brain damage, though my study only recorded a min SpO2 of 90%.

Before CPAP, How many times do you actually remember waking up in middle of night?

From someone else with apnea: absolutely none at all.

I didn't have to use CPAP to treat it though, so other people's experiences might be different.

Re: What is the real reason we sleep?

#54

Post by MollyR »

gregatragenet3 wrote: post #10
carsongross wrote: post #8

Conjecture (half serious): we won't get strong AI until we figure out why we need to sleep.

Probably related. Mammals dream, and we humans experience time in dreams much faster than the actual passage of time. Dreaming is likely the same mechanism as 'experience replay' used in AI reinforcement learning. We're just training our neutral networks using minibatches of our experiences from our waking hours.

Yea, I would suspect this is true as well. Upenn had some sleep studies that were looking this idea, I'n not sure how mature the research was/is though.

Re: What is the real reason we sleep?

#55

Post by [deleted] »

Dylan16807 wrote: post #35
yason wrote: post #21

What if the question was phrased as what is the real reason we wake up and dedicate some conscious time for our mind? Surely, because in the physical world we live we need to arrange for some time to deal with the unavoidable practical things such as finding food and shelter. Then, after a long enough period of this activity focused on these very tangible, physical and physiological constraints we can finally say we…

Doesn't make sense to me. To take care of those needs, we don't need to be awake nearly as much as we are. On the other hand, staying awake all the time would have moderate efficiency benefits and provide a lot more protection from threats. So we should either be sleeping a lot more or barely at all; the middle ground has no benefit under this model. The model of sleep as recovery works a lot better for the durations…

[deleted]

Re: What is the real reason we sleep?

#56

Post by meshr »

I have another idea why we sleep: the reason lays in physics, it happens because the sun is not shining all the day. So the living creatures had to create a mechanism to be more active while daylight. That is why all “garbage collection” activities were moved from daylight activity to the night.

Re: What is the real reason we sleep?

#57

Post by LouisSayers »

One thought I've had recently: What if being "unconscious" isn't unconscious at all - what if it's a different form of consciousness?

For instance, it deals with the internal world of our body, maintaining and dealing with issues as they happen. It's responsible for releasing chemicals to get a desirable action from our 'conscious' self. It gives us rashes in an attempt to change its environment.

I haven't thought about this too much, but in the very least, I think it's an interesting thought experiment. Has anyone actually tested that our 'unconscious' is indeed unconscious?

Re: What is the real reason we sleep?

#60

Post by dhammack »

carsongross wrote: post #8

Conjecture (half serious): we won't get strong AI until we figure out why we need to sleep.

My hypothesis is that all RNNs (and in general complex dynamical systems) need to be reset periodically. If run for too long without resetting, they tend to get stuck in strange states, blow up, or cease activating. You can see this effect by running a generative RNN model for a long time - eventually the output is garbage.

Under this model the next obvious question is why it takes so long to reset the brain's state. Maybe it can be done faster.

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