Fun fact: people didn't always do one big sleep. We used to go to bed when the sun went down. Slept for several hours (3-5) and then rise, eat something or go for a walk. Then you'd go back to sleep until morning. So if you read old stories and they talk about a second sleep...

i should be sleeping right now but I'm watching a video about sleeping

Me at 3am: I should be asleep but instead I MUST LEARN THE SCIENCE OF SLEEP in order to sleep better of course...

"You shouldn't use electronic devices for 1 hour before sleep." Okay, I turn off my laptop at 4 AM. What the heck should I do for another 1 hour in the dark?

I used to call the circadian rhythm the “Canadian rhythm”

Does science have anything to say about the euphoric feeling of waking up and finding out its only 6am so you get to sleep more?

“Sleep, those little slices of death; Oh how I loath them.” ~ Edgar Allan Poe

I’m going to go ahead and get my 25 years of sleep over with now so I don’t have to worry about it in the future, I’ll see you guys in 2043 ✌🏻

I once woke up with sleep paralysis after dreaming about being sexually assaulted. It was one of the most terrifying things I have ever experienced.

As a stay at home mom (for now) yes, I get sleepy around 2 pm (always have, even when working), but I take a nap for about an hour or an hour and a half. I still go to bed around 11, and get up around 7:30. It seems to help me tremendously.

“the circadian rhythm is synced with day/night cycle” me: *laughs in graveyard shift*

Oversleeping may be tied to undiagnosed Sleep Apnea, which I think is fairly common. And untreated Sleep Apnea definitely causes increased blood sugar, blood pressure, and other bad things.

6:53 My brain: Saving changes and defragmenting data My Alarm: Cancel

I don't have any kind of sleep pattern . My husband , is totally different . When he lays down and puts his arm over his head . ...he is completely asleep within 2 minutes . The very truth . We have been married for 46 yrs and he has always been this way. Lucky for him.

Literally uploaded at 6 am. Is this a sign? ...nah _makes another cup of coffee_

25 minutes of sleep lost

I play all of hanks videos on a playlist on shuffle I made. Its helped with my insomnia so much. His voice is very enjoyable to my ears and his facts keep my mind occupied from my bad thoughts.

I remember having sleep paralysis. It's like sleep, but you're actually afraid of losing consciousness.

"so go ahead and take that nap, or after this episode!" bruh im gonna fall asleep DURING this episode

Watched this almost immediately after getting up from my post-thanksgiving nap :) I dunno about other people, but 15 minutes more sleep sounds like a godsend. Pre-medication it took me about an hour to fall (deeply) asleep. Now it's closer to 1/2 hour. Even just 45 minutes would have been a wonderful improvement.

Sleep Paralysis has happened to me twice. First time it was kind of the classic pressure on chest, feeling of terror and feeling of a malicious presence. The second time it happened though, I had already learned about it. So when I realized what was going on, I swore in my head, laughed and then fell back asleep.

HEY dont just try to walk past the fact that part of your brain is blue

There was this odd time when it felt like I was half-asleep… in a very literal way. I felt like a dozed off in class one time and those I was watching what was happening around me and more or less understanding what was going on, I also was having a dream about my grandparents. At one point I start seeing more of my dream then the waking world, but the thing I’m hearing in the waking world is still being registered; so it appeared as if my grandparents were talking with the voices of my classmates.

Hey SciShow, could you put something in the title that indicates that a video is a compilation or a review or something? As a longtime viewer, it's a bit disappointing to be notified that there's a new video, only for it to be a bunch of videos I've already seen before.

BRAIN: It’s around 5 o’clock Me:*Checks time* Phone:It is 5:04 This really happened to mee

Headline news, sleepy drivers cause more accidents than drunk drivers.

I wish napping during the job would be allowed....

I have mixed sleep apnea (obstructive sleep apnea + central sleep apnea). When I found out what central sleep apnea was, I said "Oh, so my brain is trying to kill me?" My doctor said "I wouldn't call it that, but...yeah." When I had my sleep study, the nurse said I had the highest number of apnea events she'd ever seen. (Whee! I win! lol.) My AHI was 143. (I stopped breathing 143 times per hour.) Mine is treated very well with an ASV (Adaptive support ventilation) machine. That's a CPAP machine that also forces air when you stop breathing. It's a non-invasive ventilator. I now sleep like a baby. Well, probably better than a baby. Babies wake up a lot. Treated with ASV, my AHI is now like someone without apnea (AHI of less than 1 to 3. Less than 5 is normal.) A lot of people hate when they get on CPAP, I loved it. It basically improved my life 1000% starting with the first night, about 5 years ago.

I didn't realise how much Hank jokingly complains about streaming until this video XD

Green: People often feel sleepy from 2 am to 4 am and 2 pm to 3 pm Me watching this half asleep at 2:30 pm: 💤

This quarantine really disturbed my body's rhythm and I am watching this @ 6:21 AM without/can't/won't sleep anytime soon. I miss sleeping 😭

I NEEDED THIS VIDEO! Thank you so much this was incredibly informative and helped me realize my own issues involving sleep. I feel a lot better about my conditions and I believe it's because of my super messed up sleep schedule/cycle. I need to FIX my sleep.

Video comes out on the brink of my insomnia relapse, this should be fun

Thank you for this video. I have Asperger's and associated genetic insomnia, so I'm always looking for a better understanding of the complicated processes involved with sleep, or lack of it.

I always thought my sleep paralysis were instances of feverish hallucinations! In my case the panic and anxiety/confusion was about being stuck in that inbetween state (not fully awake or fully asleep). I often lucid dream so having sleep paralysis frightens me because unlike nightmares I wake up when sufficiently freaked out. Instead the anxiety and stress grows because I'm aware of my physical situation which I can't control (lying in bed/can't move) The worst is when it's accompanied by vivid visual hallucinations. These hold me hostage to the point I'm convinced that I can only be freed once I complete a nonsensical or ridiculous "mental task". The most vivid one I can remember was having to build a child meccano set. All the pieces were laid out in the air. Despite it being child's play the task seemed so impossible and as confusing as rocket science (for a non scientist). The hope of fully waking up or going to sleep were just out of my reach since according to the hallucination I just absolutely had that responsibility to build it until completion.

98% of these comments *I'm literally in bed watching this, who else?* 2% Muscle Hank....Because he Hella thicc

MUSCLE HANK WHERE ARE YOU I NEED YOU

10:09 I actually had this happen to me a few years ago. For reasons never determined, I went about five days without sleep, and by day three, I had completely lost the plot - except for “Downton Abbey’s” plot, because for some reason I thought that was real and was begging my now-wife to go help Anna the maid. I was also absolutely convinced my wife had let someone in the house and was lying to me about it. It was bad enough my (now former) doctor was actually going to have me committed to a mental health facility on a 72-hour hold. (Why he didn’t just write me a script for a sleeping pill just to kickstart my system was also never determined, nor why no OTC meds or even alcohol, which tends to make me sleepy, didn’t work.) It only ended when my body basically just shut down, I guess; apparently, I walked back to our bedroom, laid down and was out for the count. I don’t remember much from days four or five, and despite having survived 17 blood clots thanks to an aggressive and incurable genetic disorder, I’ve never been so scared or ashamed in my life as I was after that experience, and to this day feel absolutely terrible for what I put my wife through. I’m even more terrified of it happening again. tl;dr screw you, locus coeuruleus

Why do I feel warmer after sleeping than before? My house is the same temperature when I go to bed as when I get up in the morning, but I always feel chilled in the evening before bed, adding sweaters and fuzzy socks that I would be way too overheated to wear in the morning. Is it just based on metabolic rate, or is there more going on?

My sleep problems started me convinced that it simply had insomnia. I had the pattern of nights of believing I was staring at the ceiling all night, then after a few nights of that, I would finally sleep through the night. On the nights I was sleeping, I realized I was waking up around 20+ times a night. I kept a notebook in my bed and every time I roused, I put a check on the page (I did not turn on the light). In the morning, I counted the checks. My doctor sent me to a sleep specialist who ordered a sleep study. I thought I had insomnia that night only to be shocked to find out I had been in and out of sleep during that time. I never went into deep sleep or REM sleep, when I began to have sleep apnea in stage two, my body roused me to keep me breathing. I was sleeping 10 minutes at a time before waking up--and since I was not aware that I had dropped off to sleep I thought I was not going to sleep at all. The second half of the night I has a CPAP mask on and the technician was trying to determine the proper pressure for me. She ran out of night, however when she got me around half of my therapeutic pressure, I dropped into REM sleep and stopped breathing 53 times an hour. Close to once a minute. No wonder I was not getting to a deep sleep. With the CPAP machine at the proper pressure level for me, my apnea incidents are around 2or 3 an hour. What a change!

Letting the sun dictate your sleep schedule is not possible in Norway. Then I would be sleeping from 8am to 4pm.

It *is* also true that each person has different sleep needs. And, for some folks, it's simply not possible to stay in bed for eight hours; for myself, it's just not possible to rest when your back and joints are screaming at you to get up and move.

If you can, get in bad 9 hours before you need to get up. 15 minutes to fall asleep, 8.5 hours to sleep, and 15 to press snooze or whatever of that sort

What most usually keeps me awake past bedtime is watching youtube videos like this one; it's an addiction.

I’m a nurse, so sleep pattern is basically shite 😑

I feel so called out by this episode :")

I can’t remember the last time I went to sleep and stayed asleep until my alarm went off

Another great vid. Thanks SciShow❤️👍👍

i really enjoy these compilations! all videos of an interesting topic nicely packed together into one single video.

I've nocturnal epilepsy. A side effect for some sufferers is that they've trouble falling asleep and keep waking during the night. If you have epilepsy, sleep is reeeeeally important to stop seizures so, not good. I ended up anxious and scared about sleep which made things worse so I was put on a second seizure drug especially made for people like me - it's basically a sedative. I've never been happier and now happily sleep for 10 hours straight!

Great video about sleep guys. As a person who has suffered with Chronic Fatigue Syndrome, Fibromyalgia & other fun problems I am not one to skip a nap when my body asks for one. I had a very, very tough time adjusting my circadian rhythm back to a 'Normal' Daytime rhythm. But now days I'm up before the sun usually and to bed & asleep around 10 PM. I still bring my phone with me to bed to watch videos, but now days there's a way you can remove the blue light on the phone to prevent issues. I for one am thankful for that. Hope everyone at SciShow had a wonderful Thanksgiving! 🦃💞🥂

I have acute insomnia, sometimes chronic.. I suffer from nightmares and bad dreams. Until I started telling my self out loud (before sleep) NO Bad or horrible dreams, no dreams about the past Only good dreams and sleep without waking.. The dreams have settled and I don't have so many bad dreams... sometimes I don't have any bad dreams. But still dream.. I don't wake as much as I used to.. (sometimes I'd be awake 2 hrs through the night but it's got down to an hour and and hour and half sometimes. But I'm not waking as much as I was before.. Thanks scishow for your great videos. You all are amazing

I've had sleep paralysis so many times now that even my sub-conscious brain is used to it. Like, when there some creepy nightmare figure sitting on my chest telling me that its going to burn my house down, my half-dreaming self is all, 'Cool story, dream hallucination. Just wait for my brain to catch up with me and then we'll see who ceases to exist.' It's actually oddly satisfying.

I like these compilation videos.

Just clicked this. Super excited to see such a long scishow video

Years ago after my divorce I had never been on my own before. I went from living with family to a husband and/or kids. I was in my 40s living in my first apt. I had alarms on doors/windows but every night I was hearing someone moving around in the kitchen. I wasn't sleeping well, I was working full time and going to college full time. I was going into paranoia and no one could tell me why I was hearing someone in the kitchen but night. The dr. gave me amitriptyline and after the first really good sleep I was able to understand I was actually hearing the heating unit located in the baseboards of the front room & kitchen. Amazing what a good night's sleep can help and my goodness what we undergo when we don't get it!

Great video to post just when I was going to bed.

I have never agreed so hard to something like Michael's intro statement to this compilation.

I swear there is not a single bit of melatonin in my body. Falling asleep for me is almost impossible. It takes me like 5 hours.

I came here to watch a video about sleep, now I'm watching an ad about the lego movie two that is also showing the first movie as the ad in itself.

Holy sh*t! A sciShow 25 min video? YES!

Scishow is my favorite youtube channel by far

I've been using a CPAP machine for a year and a half now and have learned that I never knew what a good night's sleep was before using the machine.

My teacher’s alarm for lunchtime often makes me jump or makes my heart skip a beat cause’ I’m so used to the sound of the alarm waking me from my sleep

Haha, I usually wake up around 3:30 or 4 o'clock. AM. Without an alarm. I also fall asleep on the computer ALL the time. I fall asleep running youtube videos, too.

FINALLY A SLEEP VIDEO

SciShow, i need to let you know that I started watching this video and it made me pass out on the floor and sleep there all night

What is harder is getting my cat in sync with going back an hour!

The first half of the night is spent relieving sleep pressure, the second half is more concerned with the brain. Glutathione is a redox buffer that regulates ATP production in the mitochondria. I have been using liposomal glutathione for about 20 months now. I "suck" 2 - 4ml in the morning and I find that my REM sleep is greatly improved. I used to wake at 4am and not go back to sleep, now I awaken after 7 - 8 hours of nutritious sleep, usually after an imaginative dream. I'm trying to spread the work, I want people to study this simple treatment further

I'm suprised Hank didn't mention the 'Old Hag' phenomenon! A hugh amount of people seem to have a common 'hallucination....upon awakining they often can't breath because of a horrid old woman hovering over them in a menacing manner! Ascribed to 'wakeful dreaming'...ummmm...In my 70s acid culture we had a belief that during LSD trips if more than one person has a hallucination...it's not!!!

This explain why I am so anxious, tired and paranoid all the time.

More Michael Aranda! 💙

“When we mess with that things can get out of whack in a hurry” Going in public when your drunk and trying to act sober

I stayed up for more than 24 hours playing video games recently and towards the end I started hearing music that wasnt there lul

I just experienced sleep paralysis last night. It felt like hours before I could move even slightly. I was finally able to sit up but not move anymore. It was pretty scary IMO. I felt so anxious

Love your videos keep it up guys science has been with me since a child

Thanks a lot SciShow. It's midday Friday, I'm at work, and your video is making me drowsy. :P

Yeah, well, since I was five years old, a huge cup of coffee with little or no sugar has always been a sure-fire way for me to be unconscious within and hour. Caffeine - puts me to sleep. Even better than alcohol.

I have never awakened feeling refreshed. It takes me hours to come around and be normal.

I use a laptop in bed every morning at 4am & fall asleep with no problems. Wake time is noon. the sun makes me sleepy.

As a person who grew up in Alaska I can't take the whole circadian rhythm idea seriously until someone explains how it works for Arctic peoples.

You can turn down the output level of a video screen in a dark room with curtains drown. This way the eyes will also be adapted to walking around unlit rooms.

Thanks for good information.

Great explanation - really fun to view too. Thanks.

Learn so much form this amazing channel 😎👍

Chronic insomnia since I was a toddler. I am 50 years old & my sleep has barely improved over all that time. Yoga, sleep aids, meditation, all kinds of exercise from gym work outs & weight lifting to swimming...none have cured my insomnia. The ONLY thing that made a marked difference was when I was a runner.

I went 14 days without a single minute of sleep back in december of 2015 . I fainted a few times and saw a whole lot of hallucinations and was almost in a vegetable state for last 5-6 days. I have recurring insomnia and very bad anxiety disorder. Turns out after the first 3-4 days of not being able to sleep due to scheduling and work related stress, being anxious about not being able to sleep was what was keeping me from sleeping. Had to take anti anxiety pills to finally be able to sleep. Thankfully I haven't had another similar episode. I've had smaller insomniac episodes quite a few times, but they generally resolve in under 4-5 days.

I watch this video about sleeping to help me fall asleep. Works every time

this younger teacher brilliantly appears in many videos how is it possible for him to understand various branches of science it's stunning .

Great, a clip show, everyone loves clip shows

Interesting video. One of, if not THE, best in getting into a question I've wondered about for years = that being why do we sleep and rest is a lazy answer as our bodies, obvious, do not rest...at least most of our bodies continue to function 'just' (?) as they do when we are awake. Around 11:30...the kid that stayed up 11-days (typically after 2-3 days people become schizophrenic), this, I think, provides major insights into the core reasons of why we sleep. Fascinating.

I'll grab a coffee to stay up for watching this.

Anyone else sleep so deep that you can wake up walk around, converse with people, go back to sleep and not even know it happened? No? Ok than just me...

While I nodded, nearly napping, suddenly there came a tapping, As of some one gently rapping, rapping at my monitor. “’Tis some video,” I muttered, “SciShow on my monitor- Only this and nothing more.”

Happy Thanksgiving y’all.

Would’ve appreciated more info on narcolepsy! As a person suffering from narcolepsy I’d love to get more of a scientific explanation :)

While doing today’s crossword puzzle the clue “Sleep disorder “ popped up 😂

I've found that when I have sleep paralysis it helps to do math problems or trying to recite books and poems. I don't know why but my guess is that forcing your mind to wake up may help stop the paralysis.

I got the whole LEGO movie as an ad lmao

I love how this channel reads all the papers... I trust y'all