Subscribe
Share
Share
Embed
Discover the exciting latest breakthroughs in brain science that can unlock your full potential. This engaging journey is packed with clear explanations and practical, actionable tips that can truly transform your life for better.
Dr. Marc Milstein: [00:00:02] Take your age, divide it by ten. Do you have that new number or close to that number? That's the number of years in your life that you've spent dreaming. How does that feel? It can feel like quite a bit of time. So what we're going to talk about today is our understanding or our latest understanding of the brain science of dreams, why we have them, what's actually happening in our brain when we're dreaming. How do we have better dreams? How do we have less bad dreams? And also, how do we even use dreams to our advantage?
[00:00:33] Hi, my name is doctor Marc Milstein, and welcome to the Best of Your Brain podcast. Have you ever had that dream where you are losing teeth, maybe failing a test, or you have the stress of taking an exam, finding a hidden room in your house? Whenever I have that dream, I wake up very upset that I don't have more storage. Or maybe you have the dream that you're being chased, or you can't run, or you can't dial that phone number or put that code into the alarm to turn the alarm off. Why do we all have similar dreams? Well, there's about 50 different what we call dream motifs, different themes. And if you go around the world, many countries and many societies have very similar dreams. We just have to take a moment and take one step back and ask the question, why do we dream?
[00:01:17] We also realize that there are certain dream motifs. There's over 50 of them. These are themes that seem to be consistent in a lot of people. So let's look a little bit deeper into what's happening in the brain to understand why this time is so important and so valuable. When we're asleep, we're not just asleep in the sense that our brain isn't just off. There's actually things happening in our brain in a specific cycle, and we sleep in this 90 minute sleep cycle, and we just pretty much keep repeating it throughout the night. And we can break it down that essentially we sleep in this cycle that has these steps. You first fall asleep and you're in something called light sleep. Then you go into a deep sleep and then you dream. That's REM sleep. Now, if you wake up in REM sleep, you're much more likely to remember your dreams. But what's happening during this REM sleep? Well, REM stands for Rapid Eye Movement. If you've ever slept next to a dog or another person, you see their eyes going back and forth through their eyelids. That's rapid eye movement. Now, we might think that the eyes are moving together when they're undergoing rapid eye movement, but actually what we now understand is that the eyes are moving in different directions, like one eye is moving over here and the other eye is moving over here. It sounds kind of like The Exorcist or a horror movie.
Dr. Marc Milstein: [00:02:26] But what's interesting about this is that if you're dreaming about something that's like a goal and you want to get something done, then your eyes actually sync up and they work together. Now, while you're dreaming, while you're in rapid eye movement, there's this massive amount of electrical activity happening in your brain. It's almost like your brain is awake, but certain parts of the brain are off and certain parts of the brain are highly stimulated. And while you're having this massive, essentially electrical storm in your brain, you're also sending a signal down your spinal cord that's actually paralyzing you from the neck down. So you are meant to be paralyzed while you're sleeping, while you're dreaming, I should say, during the dream state? And if we weren't paralyzed, what would we do? We would very likely act out our dreams. And if you're dreaming of boxing or wrestling, that's dangerous to you, or somebody that could be sleeping near you. So really, we're supposed to be paralyzed while we're dreaming. It protects us. But have you ever had that feeling where you're falling, like you're almost falling off of a building? It turns out that's actually not a dream. That's actually your body relaxing as it enters into the sleep cycle. And that relaxation of your muscles actually tricks your brain into thinking that you're in a falling state, and then you tense up. So that's not a dream. But do you remember your dreams? And 95% of all dreams are actually forgotten.
Dr. Marc Milstein: [00:03:46] And I mentioned earlier that if you remember your dreams, you very likely woke up during them. But some people say, "I don't remember any of my dreams. Does that mean I'm not going through REM sleep?" You're very likely still having REM sleep. And they've actually put people in brain scanners while they're sleeping. And they find that people who remember their dreams, they're actually paying attention to them while they're dreaming. There's parts of the brain that are active, that are involved in attention, that pay attention to the content. People who don't remember their dreams, oftentimes they're just like their brain figures. This just isn't important. It's not interesting enough and they don't remember it. Now that REM sleep cycle, when you first enter your first sleep cycle of the night, you're actually only dreaming for about five minutes. And then every time you reenter the cycle and you go back to the dream state that REM state, the REM state gets a little bit longer and longer. And by the time the morning comes, you're dreaming for about 20 to 30 minutes. You're much more likely to remember your dreams in the morning because you're just spending a lot more time in the dream state.
[00:04:45] Now, have you ever had that feeling where you can't run in your dream, or you can't make an action? Like I mentioned earlier, you can't dial the phone number or put the code into the alarm? What's actually happening in our brain when that's happening is that there's a part of your brain called the prefrontal cortex, and that's like the boss of the brain. It's like the CEO. And when we're dreaming, that part of the brain pretty much takes a break, and it allows other parts of the brain to play and be creative. But that's the action oriented, goal oriented part of the brain. And if that's off, it's very hard to take action. So that's why we have that feeling when we're dreaming, oftentimes like, I can't run, I can't dial that phone number. I can't fill out the form like I need to now. While the prefrontal cortex is taking a break, it's kind of like the office or an office environment where if the boss is away, what happens? People play and that's what's happening in the brain while we're dreaming. It allows parts of the brain to interact with each other in a way that wouldn't happen during the day. And that leads to a lot of creative thinking. There's been all these stories about how, like, for example, Paul McCartney says a lot of his songs were written in dreams. Frankenstein. That idea came up in a dream by Mary Shelley. A lot of great inventions were thought of in dreams, and it's really rooted in this idea that the brain plays when we're dreaming.
Dr. Marc Milstein: [00:06:02] It uses information in an out of the box thinking. We can actually use that to our advantage, we'll talk about that in a moment. But what's the point of dreaming? Why do we spend this time dreaming beyond just this creative state? Well, there was a study done and they took a bunch of undergraduate students, and they divided them into two groups, and they had both groups do a maze, like imagine a rat in a maze. But these were people doing a maze and half the people after they ran the maze, they said, "okay, take a 90 minute nap so you get some REM sleep". And the other group, they didn't have them sleep, no nap, no sleep. And then they had them do the maze again. And the people who napped had REM sleep and actually dreamed about the maze. When they redid the maze, they did it ten times faster than the people who didn't fall asleep and didn't dream. So if we don't get a good night's sleep, we just won't remember the things we learned that day nearly as well because we miss out on that memory strengthening process. And just to highlight the importance of this, we now know that sleep apnea, where somebody could be waking up hundreds, if not thousands of times throughout the night, that's disrupting REM sleep. And we see that people who have sleep apnea and they don't treat it have a much higher risk of memory loss because they're missing out on that memory strengthening process.
Dr. Marc Milstein: [00:07:18] Now, have you ever heard that idea that you're studying for a big test or an exam and people say, should I go to sleep or should I pull an all nighter and keep studying? Well, based upon our understanding of how the brain works, we really should just go to sleep because that allows us to make those memories stronger. Have you ever had that experience where you're learning something and you wake up the next morning and you're like, I know this better. I feel like I know the information in a much stronger manner. Well, that's really your brain taking that information and making those connections stick while the brain is also making some memories stronger. There's also something else that's happening in the brain called synaptic pruning. And it's kind of like your garden or your desk. And the idea that in order to make your garden look good, you have to get rid of the weeds or parts of the garden that don't look good anymore, that aren't needed. Well, the same thing is happening in the brain while we're dreaming. The brain is actually finding all these connections for memories that the brain determines it doesn't need anymore. Maybe useless information, things that aren't important and it's unhooking those memories. You see, part of remembering is forgetting. It's kind of like your desk.
Dr. Marc Milstein: [00:08:20] If it's not organized, it's hard to find anything. Same thing in the brain. And if we think about it, oftentimes our dreams can be a weird combination of things that we just experienced and things we haven't thought about in a really long time. But in a really strange way of thinking about them or a strange story version. Remember, the prefrontal cortex is off, so it plays with old information and new information. Now we also realize that part of what's happening when we're dreaming, besides being creative, besides strengthening our memory, we also realized there's something called threat rehearsal or acting out or rehearsing something scary in our lives. Something that could be stressful. If you're having that dream about, you know you're back in high school taking that exam or somebody chasing you. What we really believe is happening there is the brain is rehearsing that stressful experience so that when it actually does happen, our brain is better able to handle it. And oftentimes, it's not the exact thing that we're about to go through, but maybe something in our past that we've experienced that's stressful and our brain is using that coping strategy or trying to rehearse it or play it out so that when we do have that stressful experience, it's on the horizon or something we have to do the next day or the next week, we're better able to adapt or handle it. So our brain is actually rehearsing.
Dr. Marc Milstein: [00:09:38] And that makes sense when we think about some of the dreams that we have and why they're so stressful. Or you might have noticed that sometimes you have recurring dreams and there's some real brain science here. Remember when we were saying that when you learn something new, you make some new connections in your brain, that house, that memory. Well, that process of fully making that memory stronger takes about seven days. And there's a lot of processing that goes on in the brain where your brain wants to really strengthen that memory through the dreaming process. But what we realize is that we're going to be dreaming about what we learned that night. But because the process takes seven days, we're going to often dream about it seven days later as well. And this can cause a reoccurring dream. So you might be thinking, how does the brain know what to remember and what to forget? Well, there's this fascinating process that we're understanding now called molecular tagging. And when you have certain experiences throughout the day, they can be tagged for the connection that's made for that memory. And if it's an emotional memory or if it's something that makes you laugh or something that really taps into things that are scary. That connection is tagged as something that is important. And if you think about throughout evolution, things that were scary or things that were very unique to us, we had to remember them because they could be part of our survival or how to find food.
Dr. Marc Milstein: [00:10:55] So emotional memories get tagged as something that's very likely going to be remembered. If it's not tagged, it's something that's probably not going to be strengthened as much. And in a future episode, we're going to talk about memory and how we can strengthen our memory through how we learn things and using emotion as a part of that. We'll talk about that in another episode. But if we take one step back and we start to think about how we take all this information and how do we improve upon our dreaming, how do we make our dreams more pleasant or things that we enjoy? Or how do we use dreams to our advantage? Well, one thing to be aware of is that if you're dreaming about something that's upsetting to you, that's scary, or that's something that really is disturbing, something to consider is that that morning, not thinking about it, not talking about it. And in the past, people would often say, well, if you're having a scary dream or an upsetting dream, let's talk it out. If you're talking about it and focusing on it, what are we actually doing? We're putting it right back into our brain. So there's something to be said for saying just this is my brain doing its thing. Dreams are a way that I process information. I am creative, I have a threat rehearsal, and this is just my brain working out some things that it needs to work out and I don't need to focus on it.
Dr. Marc Milstein: [00:12:09] I can just let go of it. It can be part of the process of healing. We also realize that what we're experiencing throughout the day can have a dramatic impact on what we dream about that night. In fact, if people watch violent movies or TV shows or stressful shows, they're much more likely to have violent or stressful dreams. We also have seen studies where people will be told to play Tetris all day. What do you think they dream about? They dream about Tetris. This is why I can't play chess during the day because that's all I dream about at night. We also see that your environment can make a difference. They've actually done studies where they have the room that people are sleeping in to smell like roses. People have sweeter dreams. They have nicer dreams. More pleasant dreams. If the room smells like rotten eggs, they have bad dreams. That's a problem on its own. That probably needs to be solved as well. But the idea is that even sound can make a difference. They've done studies where they find that if people are listening to like ocean waves, they have better dreams. But if it's a haunted house sound or the sounds of a haunted house, what do you think? They dream about scary things. So just optimizing our environment and what we're doing throughout the day can make an impact on our dreams as well.
Dr. Marc Milstein: [00:13:17] Remember, our brain is just taking the things that we're experiencing throughout the day, and it's often dreaming about those things in some capacity. So if we just spend a little bit more time during the day thinking about happy things, pleasant things, we can also see our dreams. We can't completely control our dreams, but we can have a better opportunity to have better dreams that night. We also realize that if you're not happy with the ending of your dream or how the dream is playing out, there's actually some evidence that if you actually just replay the dream during the day, but change the ending, you're likely seeding your brain for that new ending that night. So for example, let's say that you really want to tell somebody off or you want to turn around when somebody's chasing you and tell them to stop chasing you or something that you want to change the ending of a dream, you actually practice it during the day. And very likely there's a better chance that you're going to dream about it that new way at night. Remember we talked about the dream of teeth falling out? Well, that can be a sign of stress changes in our life, things that we're going through. But also there's actually an interesting study that found that when people actually have irritation in their gums or something's hurting in their mouth, that that actually can cause that dream.
Dr. Marc Milstein: [00:14:30] So sometimes dreams are actually based upon things that we're experiencing physically. So if you have a dream about your teeth falling out, maybe it's time to just go see the dentist. We also realized that we can try to solve some things in our dreams. Remember, dreaming is a time when we're creative. Experiment. Try tonight. If there's something in your life that you want to find the answer to, or a better solution, or just be a little bit more creative in some aspect of your life. Just say right before bed, try to solve this specific problem for me, during my dreams, people are surprised when they wake up the next day that sometimes they have some new ideas or new ways of thinking about things because their prefrontal cortex is taking that break.
[00:15:09] So I hope you leave this podcast with some of the best things you can do to optimize your dreaming. In a future episode, we're going to talk about how you can really optimize your sleep in general, but part of getting a good night's sleep is having some good dreams. So I hope you enjoyed today and I wish you sweet dreams. Thanks so much for watching. If you'd like to receive one brain health tip per week, please sign up for my newsletter. The link is in the description in the show notes below. See you next time.