hi I'm DrJeffrey iff a sleep researcher today we're going to be answering your questions on Twitter this is sh this is sleep [Music] support at catty Wampus s it's 5:00 a. m. I can't sleep I'm eating summer sausage what is time what are circadian rhythms well I don't know why you're eating summer sausage at 5:00 a.
m. what are circadian rhythms I can answer that circadian rhythm is the drive in your body that entrains all of its functions to the 24-hour light cycle so there's a part of your brain called the supermatic nucleus that's the master pacemaker for the Circadian rhythm and what it does is it cues off of the light dark cycle so sunrise and sunset to get your brain and actually the rest of your body ready to rest at night and ready to act during the day at RG will uncore asks why do we take naps and wake up more tired oh that's a good question because there's good napping and there's bad napping when you wake up after a nap and you feel like you just got hit by a truck it's because what has happened is you started to build what's called Sleep inertia so once you start sleeping after you get past a certain point your brain gets into the mode that thinks oh we're doing this for the next 8 hours and if you interrupt it after it's gotten past that point it's sort of a rude awakening and that's why you feel super groggy after a long nap that's why when you nap you should actually nap either a very short nap maybe 20 or 30 minutes or 90 minutes so setting an alarm for a 90minut nap a 90 9 minute nap is enough time for you to go through an entire sleep cycle so going through shallow sleep to Deep Sleep up to REM but only once not long enough for you to build a lot of sleep inertia but enough time for you to actually get some of the benefits of sleeping at punk ass book joke says everybody talking about their weird Co dreams and I'm over here like LOL what does REM sleep these are actually EEG caps that measure your what's going on inside your brain so that we can see not just whether you're asleep but what stages of sleep you happen to be in so rapid eye movement sleep is the phase of sleep connected with dreams it has a couple of weird features to it so in one of the things is if we record the electrical activity happening in your brain it actually looks a lot like an awake brain in fact one of the only ways that we can tell that you're in REM sleep and not awake is one of these electrodes here actually connects to the muscles on your face and so we can actually detect the tension or the absence of tension in your face muscles and that's how we know you're in Rim sleep not just laying there awake so during Rim sleep what's happening is your brain is working to consolidate the memories that you form through the course of the day helping to harden those memories into your long-term memory things that are powerful things that are fearful things that are scary things that create anxiety all of those things are the substance of our dreams that's part of the way that you en code dreams is with fear and pain and emotion so it's probably no wonder that we're all having the same weird Co dream at Rusty kovi asks how will your brain get rid of waste it isn't sent back into the body to be processed by the organs how does your sleep play a role in it this is a really interesting question it's actually the subject that my lab studies so your brain is very different from the rest of the body in the way that it manages the waste so the brain sits in a pool of water called cereal spinal fluid and that water helps to cushion the brain from blows that happen and it actually helps the the brain which has the kind of the consistency of room temperature butter it helps it to not you know slouch under its own weight during the daytime the spaces between the brain cells which are like the pores of this sponge are actually pretty small and pretty narrow so as a result the water that's outside the brain sort of sits on the outside but when you go to sleep the situation completely changes and the spaces between the brain cells open up allowing the water that's on the outside of the brain to actually wash into and through the spaces between the brain cells collecting up the waste that's accumulated through the course of the waking day and so then this waste Laden fluid like ammonia that's produced washes out of the brain out into the the fluid around the brain and then those lymphatic vessels surrounding the brain collect it up and eventually dump it back into the blood it's like brainwashing but without being an occult at KB rabam 21 asks have you ever wondered what your brain actually looks like when you sleep like I wonder if my neurons are really just beating the snot out of each other and my dreams are the real reason I'm losing brain cells I don't think dreams are the reason you're losing brain cells you can actually see your brain when it's sleeping you can see it by MRI sometimes you can see it during neuros surgical procedures the thing about the brain that's really striking is the way that it pulsates so the brain is just this big pulsating mass of tissue and blood so you see it pulsating with the heart rate and you see it pulsating and swelling with the respiratory cycle and there's actually these even low frequency oscillations that happen as blood vessels in the brain dilate and contract those pulsations are actually part of the process driving the clearance of waste into and out of of the brain at FX Mish asks does anyone that can lucid dream have any tips on how to do it so lucid dreaming think the movie Inception is being aware of the fact that you're dreaming when you are so that you can control what's happening around you it's a little fringey but there's actually a little bit of research on this subject so there's some data that suggests that you can use transcranial electrical stimulation so stimulating your brain with electricity at certain frequencies can increase the likelihood that a person who normally can't loose a dream actually can be able to there's also some approaches in sleeping itself that seems to increase people's ability to lose a dream you set an alarm for 5 hours after you go to sleep and then wake up right after you wake up you think to yourself I'm going to be dreaming I want to wake up during my dream repeat that to yourself again and again and again as you go back to sleep your chances of go being able to know that you're in a dream when you go back into sleep actually increase between 100% % to 1,000% so it may be either through stimulation or maybe through some cognitive tricks you can actually increases your chances of being able to lucid dream uh caramel cookie asks so is like sleepwalking a real thing yes sleepwalking is a real thing so sleepwalking is more common in kids and in adolescence it tends to disappear as people move through adolescence into adulthood the interesting thing about sleep sleepwalking is that your brain is asleep and yet you can accomplish very complicated tasks so when you're sleeping your brain is supposed to be a little bit disconnected from your awareness and it's supposed to be disconnected from how your body moves sometimes those connections they can get opened or they can get closed at the wrong time so you see things like sleep talking or sleep moaning you see people who have something called REM sleep behavior disorder which is where you actually act out the things that are happening in your dreams sometimes even violently sometimes injuring your bed partner so there's a bunch of different types of things some of them interesting some of them a little scary that can happen when the processes governing sleep and your body become misaligned at Swank Farm asks how many types of sleep do we have you actually see that your brain is doing a couple of distinct things through the course of the night one set of that is called REM sleep or rapid eye movement sleep and that's the part of sleep that's most associated with with dreaming there's also non-rem sleep non-rem sleep sort of breaks into three different categories there's N1 N2 and N3 N1 is the shallowest type of sleep so that's maybe the first 10 minutes after you first fall asleep and that's the time when you're sort of most awake it's it's easy to sort of pop back up awake and two sleep is sort of the mid layer on your way to deep sleep during that phase you're a little deeper in and your body starts to actually do some funny things so that's when sometimes people will twitch and move a little bit during N2 sleep the deepest sleep is called N3 sleep or slow wave sleep and during that time if we record what's happening in your brain your brain is actually oscillating between states where everything's on and everything's off and it's doing those oscillations about one every second those are called slow oscillations that slow wave sleep is the deepest part of sleep and then you'll come back up into REM sleep where you'll typically do dreaming one of those Cycles is about 90 minutes or so during the course of the night you go through several of those Cycles maybe three or five of them later on into the night there's less slow wave sleep and more RAM which is one of the reasons why maybe we remember the dreams that we're having late in the night better at Monon AER asks what is sleep apnea I would have asked Google but I prefer a more simple answer sleep apnea is a condition where you stop breathing several times through the course of the night so it can actually be a physical obstruction to your way that keeps you from sleeping regardless of the cause the result's bad your brain is incredibly active so the the neurons in your brain are firing trillions and trillions of times a second and all of that activity takes a huge amount of oxygen and glucose and energy to keep it going and every time you stop breathing during the night you're depriving your brain for just a little while of the energy that it needs and of the oxygen that it needs and it isn't until your brain is screaming for more oxygen that you actually gasp yourself away and as you add that up over the course of many nights over weeks and months and years the added stress that that puts on not just your brain but actually your whole body can increase your risk of cardiovascular disease like heart attacks and strokes diabetes the good news is that sleep apnea much of it is actually pretty treatable with an approach called CPAP which is basically just a mask that goes over your face and it uses a little pump to sort of force air in and out and the forcing of that air in and out of out of your lungs helps to keep your airway open and keep you from stopping breathing during the night the bad news is many more of us actually have sleep apnea than know it what does it look like how do I know if I have sleep apnea well common symptoms include heavy snoring waking up gasping if that sounds like you might be worth getting checked out with your physician athalia Clara asks what causes insomnia because I literally cannot go to sleep at a decent time no matter how tired I am upside down Smiley upside down Smiley upside down Smiley well insomnia is pretty common so it's not being able to either go to sleep or it's not being able to stay asleep once you are asleep there are genetic causes of insomnia sleep apnea can cause insomnia but frequently it's the stress in our lives that can cause either acute insomnia which is insomnia that just happens every so often or chronic insomnia that happens all the time so things that are important for Sleep hygiene include going to sleep at the same time every day and waking up at the same time every day so that your body can entrain to a certain Rhythm that can become predictable it's staying off the screens for an hour before you go to bed it's it's sleeping in a cool dark room where that isn't also your office so that you can of sort of focus in on the process of either having sex or going to sleep which is really the only two things you should be doing in your bedroom at Mash celo asks what causes sleep paralysis had it twice last night scream emoji that sounds like kind of a rough night sleep paralysis is when you're laying in bed you're sort of coming out of sleep or sometimes it's when you're going into sleep you're aware of your environment around you you perceive what's happening but you can't move the rest of your body you're sort of paralyzed and sometimes it can be accompanied by visual or auditory hallucinations or feelings of fear or Terror or even feelings of Suffocation so it can be completely terrifying your body has a couple of Disconnect switches that it throws so that all the activity happening in your brain while you're dreaming or during your REM sleep doesn't cause you to act out your actions in the world around you in sleep paralysis those disconnect switches seem to get a little jumbled up so that the switch that disconnects you from awareness of your of your environment sort of gets opened so you become aware even while the switch disconnecting you from your body is still closed if we do an EEG study in people who are having uh sleep paralysis episodes we actually seem that they still seem to be in REM sleep so even though while you're aware of what's around you your brain is still dreaming and your body still thinks you're asleep it's just that you're stuck feeling awake at yatu sabes who asks how do sleeping pills work it depends depends a little bit on the sleeping pills that you're talking about so let's start with the simpler ones so a lot of people take melatonin to help them sleep what melatonin is actually a naturally occurring molecule in your body that is part of how the body induces drowsiness it's actually a part of the circadian sleep drive to help sort of prime the brain to get ready to sleep other commonly used sleep medications include drugs called sedative hypnotics like ambian which is a commonly used one and also benzodiazapines which are sort of anti-anxiety medications that can be used sometimes to help with sleep those drugs are very powerful drugs they're available only by prescription they have the potential for forming addiction and for habit forming so they need to be used under the supervision of of a physician they work by uh targeting a neurotransmitter system in the brain which dampens down neural activity and to reduce arousal in the brain to help you sleep many of the Sleep medications don't produce the same type of natural cycling of sleep that your brain wants so if you suffer from an insomnia or if you have other sleep issues other approaches like improving your sleep habits or even cognitive behavioral therapy can be actually more helpful in helping your brain to sleep naturally than trying to accomplish that with a drug at Talia Gasco asks is it really true that you can never catch up on sleep if yes I'm actually so well you kind of are the sleep that you lose is sort of gone forever and many of the benefits of that sleep whether whether that's memory consolidation or whether that's the Rejuvenation that happens in the brain you sort of missed missed the boat but there is something that builds up the longer your sleep and the less sleep that you get that's called Sleep debt and what sleep debt is is the drive to sleep more that builds through the course of the day and it builds with sleep restriction and so when you go to sleep that sleep debt is relieved and sort of paid off so there is a sense in which you can catch up on sleep an interesting study that was measuring waste clearance out of the brain showed that if a person was kept up all night the slowing of brain clearance that happens in a person who stays up all night actually it took 7 days for it to catch up so even the second day after the sleep deprivation it hadn't even caught up so you don't necessarily catch up on Lost sleep within a day or two it may take much longer at ferling bird asks how long does coffee affect your sleep system the answer is that it's longer than most people think so the active ingredient in coffee is caffeine which targets a receptor in the brain that helps to turn off neurons and so by blocking that receptor it turns on neurons that's how coffee has its main effect on on you being awake now the halflife of coffee in the blood is between four and 6 hours which means it takes the better part of half a day for it to clear out of your body so if you want to not have caffeine influencing your sleep when you go to bed you probably need to be stopping drinking caffeinated coffee or other drinks like monster or these other energy drinks probably around 2 or 3 in the afternoon one of the things that caffeine does is it sort of keeps your your brain aroused it keeps your brain awake maybe not all the way awake so you might be skimming through the shallow parts of the shallow phases of sleep and not getting into those really deep phases of sleep that are necessary for brain health at Lindsay chat asks would love to get your tips on how to handle jet lag what do you find effective one approach is ahead of your trip if you can do this if your schedule allows you you can start moving your sleep wake cycle back an hour a day so that by the time you leave you're within an hour or two of your target time zone so if you're going to Europe and it's a 6-h hour difference 6 days ahead start moving your time to go to sleep ahead 1 Hour 1 Hour 1 hour so that by the time you leave you're going to bed at 6 p. m.
