A Sleep Scientist Excavates the World of Dreams  ## Metadata - Author: [[Fresh Air]] - Full Title: A Sleep Scientist Excavates the World of Dreams - Category: #podcasts - URL: https://share.snipd.com/episode/d65ecb16-5f68-4ae9-b1a5-88e929a6ef35 ## Document Notes ## Highlights - **Dreaming As Overnight Emotional Processing** - Dreams help process recent emotional memories and form associations to adapt for future situations. - Nightmares occur when intense emotional memories disrupt sleep and jolt us into wakefulness. Transcript: Tonya Mosley And why do some dreams turn into nightmares? Michelle Carr Couple decades of dream science, we've started to uncover some of the, what we think are some functions of dreaming. And in particular, it seems like in dreams, we're kind of processing our recent experiences and memories, and especially those memories that are really emotional and important. So significant things that happen to us during the day. And during dreams, it seems like we're kind of reworking recent memories and maybe making associations to other things we've experienced in the past, trying to learn how to deal with These scenarios and how to adapt. And it seems like dreams are kind of preparing us in a way for what's to come the next day. So they seem like they're supporting some adaptation for humans. And why do they turn bad? Well, of course, we all experience stressful things and kind of difficulties and conflicts in our life. And when these are really more severe, when we go through trauma or severe adversity, this can trigger nightmares. ([Time 0:03:12](https://share.snipd.com/snip/0bc8460f-abc2-4041-81cc-a0dbafd9e77e)) - **Lucid Dream Sparked A Career** - Michelle Carr experienced sleep paralysis in college and chose to relax instead of forcing wakefulness. - That decision led to a vivid lucid dream that inspired her career in dream science. Transcript: Michelle Carr Yeah, when I was in college, I was actually still having something called sleep paralysis, which is where right when you're waking up from a dream, your body is still kind of physically Paralyzed and it's often a really frightening nightmare experience. And this happened to me once in college and I was able to, rather than like really forcing myself to wake up, I was able to kind of relax and to stay asleep. And I felt like I woke up naturally, but what happened is I went into a lucid dream, which means I realized that I was still asleep and I was dreaming my dorm room bedroom, essentially. It was fully vivid and it felt very realistic. And it was a really simple dream. I was just sitting in my dorm room, kind of looking around. But I was just so fascinated at how just moment by moment my brain was producing this completely immersive simulation and I was inside of it experiencing it while I was asleep. And that just really fascinated me. ([Time 0:05:33](https://share.snipd.com/snip/167a5d48-ca11-43ee-87f3-fde2e5982a76)) - **How Dream Labs Capture Dreams** - Sleep labs mimic comfortable bedrooms while recording brain, eye, muscle, heart, and breathing signals. - Researchers watch subjects remotely and wake them to collect immediate dream reports. Transcript: Michelle Carr Lab is actually very similar to kind of a sleep clinic in that we, you know, we invite subjects into the lab. There's two bedrooms that really we try to make them look like comfortable bedrooms, like in a hotel with a typical, you know, a nice bed frame and a bedside lamp. And we try to make it kind of warm and homey rather than a, you know, a hospital bed or something like that. And before the subjects go to sleep, we hook them up to a bunch of different electrodes, a bunch on their scalp to measure brain activity. Some on their face, measure their eye movements and their muscle tension. And we can even measure their respiration, their heart rate. So all sorts of signals, essentially, that we measure while the person is sleeping. And while they're sleeping, actually, the experimenter is sitting in another room nearby. And we're watching, you know, a video of them and also watching essentially all of their brain and body activity on a screen. ([Time 0:07:11](https://share.snipd.com/snip/f589f8d2-3141-49ca-b657-04c4739bafb7)) - **Use A Specific Prompt To Improve Recall** - Ask sleepers: 'Can you tell me anything you were experiencing just before I called your name?' to boost recall. - Encourage lying still and allowing any thoughts, feelings, or images to resurface for faster dream reporting. Transcript: Michelle Carr Actually, so when dream science first came around, they did ask the question, what are you dreaming about? But over time, dream scientists realized that this was actually essentially limiting dream recall, because people have a really stereotypical and biased view of what a dream is. You know, we think of just these really narrative and elaborate and bizarre stories, like that's what a dream should be. But when we wake people up in the lab, we just ask them, can you tell me anything you were experiencing just before I called your name? And we ask them to lie still and to just allow any experience, any mental experience that they had to come back to mind. ([Time 0:08:31](https://share.snipd.com/snip/d684ec2d-1fbb-4b41-9093-7b2de8675e3e)) - **Nightmare-Prone People Are Highly Sensitive** - People prone to nightmares tend to be highly sensitive, imaginative, and emotionally perceptive. - That sensitivity correlates with creativity and vivid daydreaming, offering upsides despite distressing dreams. Transcript: Tonya Mosley So they're more creative, they're more perceptive, more empathetic. I mean, is that an overlooked upside to the issue of nightmares? Yeah, definitely. Michelle Carr This was something that I found during my doctoral work, and it was kind of a surprise at the time, although I will say that other dream researchers had started to point to this before, That many people who have nightmares, they just, yeah, it seems like they're just very highly sensitive people, meaning they are really, they're very perceptually sensitive. They process the environment more deeply, and it's very highly correlated with things like creativity and just feeling things more deeply and aesthetic sensitivity. So even of those people who have nightmares, sometimes they'll say, even though I have nightmares, I use them as artistic inspiration. Or besides my nightmares, I also have really vivid lucid dreams, and I have a really vivid imagination. We actually looked at this in the lab. We asked people to just daydream for a few minutes. And what we saw is that the people who have nightmares, they were having these really bizarre and vivid and immersive daydream experiences. So they have a really prime access to their imagination, essentially. ([Time 0:09:26](https://share.snipd.com/snip/0befdf39-82a3-4042-a0e9-6dad3c2b96e7)) - **The Body Shapes Dream Content** - Dreams incorporate bodily signals: heart rate, twitches, facial expressions, and respiration during REM. - The sleeping brain uses body feedback to construct dream imagery and emotional content. Transcript: Michelle Carr Yeah, I think this is still a really big open question in dream research, but it's definitely something that's become more and more of interest over time. Initially, there was kind of this view that while you're asleep, you know, your body is lying there still. And there was this view that dreamings are something that just happens in the brain. It's just brain activity and you're completely disconnected from your body. But now we realize that that's really not true, that there's all sorts of activation happening in the body and especially during REM sleep, which is when we have the most vivid dreams. So, you know, we see changes in heart rate, we see little muscle twitches, little contractions of muscles all throughout the body. And there's really rapid eye movements, there's some, you can see facial expressions, even emotional expressions. And over time, we're starting to see that there's some correspondence, that what we're dreaming is directly related to what is being experienced in the body to some extent. ([Time 0:12:15](https://share.snipd.com/snip/9e2db694-1b74-495d-b697-ed4de8076f3f)) - **Teeth Dreams Can Signal Jaw Strain** - Common dream themes can map to physical sensations, e.g., teeth-falling dreams link to morning dental irritation. - Grinding or jaw clenching during sleep can produce symbolic teeth dreams as the mind explains oral discomfort. Transcript: Michelle Carr In general, there's all types of these bad dream themes that people all around the world will report. And what's funny is for some of them, like the dream of teeth falling out, it seems like there might just be a physical component, which is that a colleague of mine, they did research that Showed that people who have this dream of their teeth falling out, they also have more dental irritation in the morning, meaning maybe their jaw or their mouth is sore. And that's because a lot of us grind our teeth or clench our jaw during the night. And so this dream might just be incorporating that physical sensation. You know, the mind is trying to make sense of why my jaw is drained. ([Time 0:13:38](https://share.snipd.com/snip/7fcf7698-67f7-4b7c-83f1-4113c5a8ff5c)) - **Stabilize Your Schedule To Reduce Nightmares** - Keep a consistent sleep schedule and get enough sleep to reduce nightmares. - Avoid late bedtimes and sleep disruptions that mix sleep stages and increase bad dreams. Transcript: Michelle Carr Think definitely having an inconsistent sleep schedule or being sleep deprived in any way can increase the incidence of nightmares. One thing we see is that people who consistently go to bed too late are more likely to have nightmares. And really anything that kind of disrupts the structure of your sleep, essentially. What we see is when you have a consistent sleep schedule and you get enough sleep, your sleep is very kind of, we call it consolidated, and it follows a very specific pattern across the Night. But when this is disrupted, you can, you know, the different sleep stages are going to get intermixed and you're going to wake up a lot from sleep and this can potentially cause bad dreams And even nightmares. ([Time 0:15:11](https://share.snipd.com/snip/8c8852b3-a257-4ffc-846a-8b7c470d446e)) - **REM Is The Hotspot For Nightmares** - REM sleep is wake-like and emotionally charged, making it the prime stage for vivid dreams and nightmares. - REM's proximity to morning explains why nightmares often wake us and feel intense. Transcript: Michelle Carr You know, we have much more deep sleep early in the night, and then we have much more REM sleep closer to waking up. It's all really important, I think, for maintaining the functions of sleep for mental and emotional well-being. And when one is disrupted, you know, it can aggravate or interrupt the functions of another state. But with nightmares, we especially see that they're most likely to happen during REM sleep, which is a really, it's a brain state that's quite, it's quite wake-like. It looks almost like wakefulness when we're looking at it, looking at the brain activity. And it's a really, there's also a lot of emotional activation in the brain and the body is almost experiencing wakefulness, but it's disconnected from the typical waking world. ([Time 0:16:25](https://share.snipd.com/snip/7b02e7e0-1f42-4517-8184-819bd9936a63)) - **Reoccurring 'Inefficacy' Dreams Rehearse Skills** - Recurrent 'inefficacy' dreams replay attempts to complete tasks and may function as rehearsal. - Even unsuccessful anxiety dreams can improve real-life performance by mentally preparing or motivating us. Transcript: Michelle Carr Yeah, so this is a very, very common typical dream theme. So, you know, the majority of people who have had this kind of dream where you're trying again and again to accomplish a specific task. And often there's all sorts of obstacles that crop up in your way. So examples are like trying to get to a flight on time or trying to get to an exam that you're supposed to be taking or you realize you were meant to take it and you forgot to study. But this theme of like trying to accomplish a goal and the whole dreams just seems to be endless attempts and often not even succeeding. And we think that this is related to kind of maybe one of the broad functions of dreaming, which is to help us to rehearse different skills. This is obviously like really important to waking life is accomplishing tasks and having goals and knowing how to work towards them and learning new skills. And we think that dreaming is just kind of reenacting these scenarios where the purpose is actually just to try to practice, and to reach towards the goal and not necessarily to accomplish It. ([Time 0:17:35](https://share.snipd.com/snip/c6e37eac-5aa8-4de8-90f6-8cb6a6359036)) - **Early Adversity Predicts Lifelong Nightmares** - Very early childhood adversity links strongly to adult nightmare frequency and themes. - Early trauma may accelerate emotional brain maturation, preserving vivid adverse memories implicitly. Transcript: Tonya Mosley Because your research actually shows that childhood adversity, even before age six, can lead to nightmares that continue until adulthood. Can you explain what's happening in a young child's brain when they trauma that creates these lasting nightmare patterns. Michelle Carr Yeah, so that's definitely something that we have found in other researchers as well, that even very early childhood adversity is strongly linked to frequency of recalling nightmares In adulthood. And there's even some theory that the actual themes of nightmares might still be related to childhood experiences. And one theory looks specifically at what's happening to children when they're very young and they're going through adverse experiences that it changes certain kind of emotional, How the brain processes emotion, essentially. It almost, it matures or ages the brain more quickly than is normal. And because of this, it can encode or hold on to adverse memories in a way that's more vivid than we typically, like most of us, forget the vast majority of our really young childhood experiences. But when we're exposed to adversity, we kind of, our brain quickly matures and tries to hold on to those more stressful experiences. And we think those might be related to the themes of nightmares and why nightmares keep recurring over time. ([Time 0:21:49](https://share.snipd.com/snip/4d8a3f70-5f70-4e2f-85e5-12911a999470)) - **Rewrite Children's Nightmares Creatively** - Help children rewrite recurring bad dreams into empowering, imaginative alternatives before sleep. - Use drawing and playful imagery or teach lucid dreaming so kids can choose safety or flight in dreams. Transcript: Michelle Carr And definitely the treatments for nightmares work just as well for children as for adults. So the basic techniques are to rewrite a nightmare. So if a child has this recurring bad dream, you could help them to come up with a new version of the dream that's more empowering and more positive. And with children, you might, you know, suggest using magic or inviting, you know, a fairy tale character into the dream and make it creative and make it fun. You can do this with drawing as well. Kids can draw like a new fun version of their dream. And you just help them to visualize and to practice imagining this more pleasant dream practices before sleep, and that can help them to reduce nightmares. And children can also become lucid in dreams. ([Time 0:27:01](https://share.snipd.com/snip/c3b1bbb3-4c60-457c-a1ad-cb0cd8b3d5d7)) - **Nightmares Usually Last Minutes** - Most nightmares occur within a single REM period and typically last minutes, not the whole night. - REM periods can be 25–30 minutes, but many dreams are shorter, often around five minutes. Transcript: Michelle Carr Sure, but I would expect that most bad dreams and nightmares, they're going to be occurring within one sleep cycle. And usually, you know, at most REM periods are reaching like 25, 30 minutes. But I would think most dreams, most bad dreams and nightmares are much shorter. They're kind of maybe five minutes or something, but I don't have data on that. ([Time 0:28:20](https://share.snipd.com/snip/933054c7-ecea-41e5-93e9-76ad331c5d4e)) - **Chronic Nightmares Impact Physical Health** - Frequent severe nightmares trigger acute physiological stress and may harm long-term health. - Studies link chronic nightmares to altered stress hormones, worse daily health, cardiovascular problems, and possible earlier mortality. Transcript: Michelle Carr Yeah, there are some studies now suggesting that having frequent and severe nightmares can have immediate and potentially long-term physical health consequences. In the first place, often when someone wakes up from a nightmare, their body is in a real state of distress. Maybe suddenly their heart is pounding and they're sweating and they can't breathe or they're breathing really quickly. So that's a real physical state of distress. And we see some alterations in stress hormones that are produced in the morning right after a nightmare. People self-report that they have less physical energy and feel in poor physical health the day after a nightmare. And more recently, there's even some research finding that people who have frequent and severe nightmares, they also report having more cardiovascular problems, potential heart Problems. ([Time 0:28:57](https://share.snipd.com/snip/d5fb6ff7-cf07-4278-bf6a-0662d5348548)) - **When Dreams Become Physical Acts** - Dream-enacting ranges from sighs and cries to full REM behavior disorder with violent movements. - REM behavior disorder often precedes neurodegeneration like Parkinson's and appears mostly in men over 60. Transcript: Michelle Carr Yeah. There's something called dream enacting. And it can happen sometimes with nightmares or really emotionally intense dreams that people maybe, you know, from a really sad dream, you might wake up and you're actually crying Or you might shout right at the end of a nightmare. So this can happen even in non-clinical conditions. But in one condition in particular called REM behavior disorder, people really, they start acting out their dreams a lot. And this often occurs in men over 60. It's actually an indication of it's often, I mean, up to 90% of people who develop this sudden acting out of usually violent dreams. They might start punching or kicking while they're asleep and they dream about these aggressive or violent things. And it's actually one of the earliest indications of someone developing neurodegeneration. So up to 90% of people who have REM behavior disorder, they will go on to develop some type of neurodegenerative disease like Parkinson's, I think is the most common, within a decade Of diagnosis. So it's actually a really, it's an early indicator that something, you know, some kind of neurodegenerative process has begun in the brain and it's resulting in this acting out of aggressive Dreams, essentially. ([Time 0:30:25](https://share.snipd.com/snip/b8bae8f8-f012-435c-9151-696fdd31b7b3)) - **Use Sensory Cues To Influence Dreams** - Use 'dream engineering' techniques like targeted reactivation: pair sensory cues with tasks before sleep. - Re-present the cues (lights, beeps) during REM to trigger memory reactivation or lucidity and reshape dream content. Transcript: Michelle Carr Yeah, there's a lot of different methods we can use that would fall under the umbrella of dream engineering, which is the study of ways and methods that we can use to influence the content Of dreaming. You know, you can use visualization and kind of mental reflection just prior to sleep already that can influence the content of dreams. But increasingly, we're looking at ways to actually almost directly interface with someone's sleeping mind, you know, while they're in the lab. And to do that, we're starting to explore different types of sensory stimulation or even brain stimulation, ways of directly influencing the sleeping body and kind of through the Sleeping body, getting into someone's dreams. Tonya Mosley What are some of the ways that you do that? Michelle Carr So one of our approaches has been, it's something called targeted reactivation, which sounds complicated, but it's basically just we're pairing sensory cues with a specific learning Task or lucid dream task prior to sleep. So people are basically associating different sensory cues, like a flashing light or a beeping sound. They associate those with a learning task. And then when they're in sleep, we represent the sensory cues, so a flashing light, a beeping sound, while someone is dreaming. In theory, this is through association. It's reactivating that memory, so what they were doing prior to sleep, that's associated with that cue. And in some of our research, we're looking at actually trying to help people become lucid by using these sensory cues. Like someone might notice their dream suddenly flashes red light or they hear this beeping sound in their dream. And we're hoping to remind them that they're dreaming. So remember, you're in this experiment. ([Time 0:33:24](https://share.snipd.com/snip/04c6847d-10bc-4c97-ae33-43e6546f8561)) - **Train Sensory Awareness For Lucid Dreams** - Practice sensory awareness (cycle attention through visual, auditory, bodily sensations) while lying awake to build lucidity. - Treat this like mindfulness so you recognize similar awareness inside dreams and become lucid. Transcript: Michelle Carr There are already many techniques that can help you to have lucid dreams at home. And one of them does, it involves really paying attention to your sensory experiences. And specifically, you can try, you know, you're lying in bed, you're still and your eyes are closed, but you try to cycle your attention through your different senses. So you try to pay attention to any visual experiences that you're having, even if your eyes are closed. And what are you hearing and what are you feeling in your body? And really paying attention. It's almost like mindfulness is how I often think of it. You're aware of what you're experiencing. And this awareness, it's the same type of awareness that you're wanting to cultivate in the dream. ([Time 0:35:18](https://share.snipd.com/snip/2410765f-2f89-436a-8c2e-6461991a002d)) - **Trackers Can Backfire If Inaccurate** - Consumer sleep trackers can help schedule consistency but often mismeasure atypical sleep. - Incorrect feedback can worsen subjective rest and cognitive performance simply by telling users they slept poorly. Transcript: Tonya Mosley What do you think about the increase in the use of sleep trackers like smart rings? Michelle Carr In general, I think a lot of people benefit from them. I mean, they can help you to keep a consistent sleep schedule and see how much sleep you're getting. The risks kind of come in that they're not always very accurate, although I think they will just get more accurate with time. But sometimes, you know, they misrepresent your sleep. And the thing is, they especially do this to people who have slightly different sleep than is typical. So sleep trackers work really well on just normal sleep, let's call it. And if your sleep is slightly different, then it's going to be worse at judging your sleep accurately. And this can cause a problem because if you wake up and your sleep tracker tells you you had bad sleep, you're actually going to feel worse. You're going to feel less rested and you're going to, I mean, research shows people will even perform worse on cognitive tests just being told that they had poor sleep, even if it wasn't True. ([Time 0:36:14](https://share.snipd.com/snip/e3c04f7f-5541-47d2-9ed9-6af0ddd8a097)) - **Tiger Nightmare Rewritten Into Cartoon** - A study participant transformed a lifelong tiger-chase nightmare into a friendly cartoon after visualization work in the lab. - The shift reduced her fear of sleep, improved bedtime habits, and changed her relationship with dreaming. Transcript: Michelle Carr There are several examples. I guess one example was a subject who had this recurring nightmare of being chased by a really realistic tiger throughout her house. I remember it actually when it was triggered when she was very young and there was this experience of her house had been broken into once and that's what triggered this nightmare. And when she participated in one of our studies over time, she was able to kind of re-script the dream through this kind of natural process of visualization. And the tiger transformed into a cartoon in one session. So it suddenly turned into this cartoon and it reminded her of a childhood cartoon that she used to watch with this friendly tiger. So it was no longer so threatening. And what she realized just after that one experience is that ever since she was young, even though she didn't think about it too much, she had really always harbored this fear around Being alone in her bedroom and going to sleep. And she really often avoided going to sleep because of it and didn't have a very good sleep schedule because of it. And just by shifting this one childhood nightmare that she had, it shifted her relationship to sleep. ([Time 0:37:21](https://share.snipd.com/snip/f8cc9d16-cfff-4833-accb-2f27bb39a566))