Big Think Interview with Shelby Harris
Shelby Harris, Psy.D., C.BSM is Director of the Behavioral Sleep Medicine Program at the Sleep-Wake Disorders Center at Montefiore Medical Center and Assistant Professor of Neurology as well as Psychiatry at the Albert Einstein College of Medicine. A graduate of Brown University, Dr. Harris received her doctorate in clinical psychology from Ferkauf Graduate School of Psychology, Yeshiva University.
As a licensed psychologist, Dr. Harris specializes in behavioral sleep medicine and CBT for anxiety and depression. She has published and presented research on the neuropsychological effects of insomnia in older adults as well as behavioral treatments for insomnia, parasomnias, narcolepsy and excessive daytime sleepiness. Dr. Harris is also a consultant for the New York Times "Consults Blog."
Shelby Harris: I’m Shelby Harris; I am the Director of the Behavioral Sleep Medicine Program at Montefiore Medical Center Sleep-Wake Disorders Center.
Question: What happens in our brains while we sleep?
Shelby Harris: So when you go to sleep at night, if you’re someone who hasn’t had any sleep deprivation, you have a very normal sleep pattern, what we tend to see is that, in adults, they go to bed and they start off by going into the deeper stages sleep. So the deeper stages of sleep are really those times of quiescence, you’re really restoring your body and we have a few different stages of sleep. So you have Sleep Stage One, Two, and then Three/Four. One is a little bit lighter stage of the quiet, non-REM sleep and then Three/Four is really deep, deep sleep. And what you want is, you actually want a number of – you want to go through all of these stages throughout the night. So people only focus on getting the really deep sleep, but in reality, we spend almost 60% of the night in the stage two sleep.
So we go through in the beginning of the night, we go into the really deep stages of sleep and we actually cycle through. So, when you go down to the deep stage, then you go back up and you actually come into something called REM sleep, which is after about 90 minutes. So when you’re in REM sleep, your brain is very active, our body is quiet, but your brain is really processing a lot of things, a lot of emotions; we dream the most in REM sleep. And then you go back down in the deep stages, and so on and so forth. And you cycle throughout so that you do about five to six cycles throughout the night. And we spend more time in REM later on in the night than we do earlier on.
That’s why people tend to remember their dreams in the morning a little bit better and if earlier in the night, when you’re in a lot of deep sleep, if someone wakes you, or the phone rings or something, you’re really confused. Really if it’s an hour or two after you’ve fallen asleep because you’re in such a deep sleep at that point.
Question: Why do we need to sleep?
Shelby Harris: Well sleep tends – we actually don’t know the function of sleep all that well yet, but sleep is a time of quiescence in the brain. When you’re in the more deeper stages of sleep – REM sleep, your body is quiet, but your mind is actually very active. So it’s a time when your body and your brain is restoring itself. It’s repairing any cell damage that happened during the day, it’s really repairing, like I said, repairing your body, but also helps with digestion, helps with memory. It has a lot of things that it’s doing while you are asleep.
Question: What happens to the brain when it doesn’t get sleep?
Shelby Harris: So, sleep deprivation, and sometimes an insomnia, which is a little bit of a different form, but just getting a lack of sleep, can lead to a number of different decrements. So, decrements in attention and concentration, being able to learn more efficiently, that’s just not as good. Also, there are motor vehicle accidents, workplace accidents, we see that a lot. Workplace accidents with people who are sleep deprived or people who work shifts and they don’t get the right amount of sleep during the day or at night.
And also, there’s a new line of research showing that people who don’t get enough sleep, they’re body doesn’t metabolize as well. And so they actually – it leads to weight gain. So if you’re not getting enough sleep, you might have difficulty losing weight.
Question: Why can’t people with insomnia get to sleep despite having large sleep debts?
Shelby Harris: Well, the actual function of the brain, not so sure yet. There’s a lot of different theories about it, but when you talk about psychologically in your brain, a lot of people with insomnia, though not all, report that they can’t turn their minds off. So, it’s not every patient that I see, but I’d say a good 70% to 80% of the patients when they go to bed it’s like a stereo is playing at an 11 or 12 and they can’t turn it down, at all. So it makes it very hard for their body to down regulate to be able to go to bed at night. And in those patients they tend to then be more awake at nights, they’ll toss and turn, they’ll think more, they get frustrated. And when that starts to happen, you really don’t sleep even more because you’re making your body tense and your mind is getting more and more active.
And you said, “sleep debt” so, in general, there are patients with insomnia who – many patients with insomnia will actually over report the lack of sleep that they are getting. They are still having insomnia, but it’s seems worse to them than actually it is. So, if they say they’re sleep deprived, they haven’t slept at all in three days; if we actually take them into a lab, most of the time we actually do see they’re sleeping on and off here and there. There might be little episodes of micro-sleeps or naps during the day, but they’re actually getting a little bit of sleep.
And we’ve looked at sleep diaries of patients with insomnia, and they’ll say that they don’t sleep for one or two days. And the body actually has a natural function, after about the third day to start catching up and you get a little bit more sleep the third night. And that’s usually what I tell my patients. When they start worrying about not sleeping, I’ll say, “Say the mantra to myself; if I don’t sleep tonight, I’ll likely sleep tomorrow, and if not tomorrow then definitely the third” because our body has a way of naturally catching up.
Question: How can we treat insomnia?
Shelby Harris: So there’s a few different ways that we treat insomnia. The first thing that we always do is we look at the cause. So, more times than not, but not every time, it can be linked to a medical problem, such as menopause, cancer, chronic pain, it can be linked to anxiety and depression. Those are the more common causes. There are some patients who just have insomnia and they’ve had it since they were a kid and we don’t quite know why. So when we look at the cause, we definitely want to treat whatever else is going on, but insomnia often because it becomes its own diagnosis and that requires its own treatment. So if somebody has chronic pain, we want to manage the pain, but we still want to treat the insomnia separately. So what we’ll tend to do in our sleep lab is we’ll do a thorough evaluation and we usually have myself, who is a Psychologist and a Sleep Behavioral Sleep Specialist, I treat the patients first. So we try not using medications initially, and we use something called **** behavioral therapy for insomnia. This changes behaviors people do in bed, none of the tossing and turning. I’ll work on patient’s thoughts about sleep, “So I must get eight hours of sleep tonight or I won’t sleep tomorrow.” That sometimes – or “I won’t function tomorrow.” That sometimes makes it very difficult for you to sleep at night. We’ll work on relaxation strategies and also changing the times you go to bed will actually make them sleep a little bit less for a few nights so their body’s natural sleep drive starts to kick in. That is very effective in about 60% to 70% of patients who do it, four to eight sessions, not even every week; it works for 60% to 70% of patients. The rates are just a good as all the medication that are out there, and the rates are actually better in the long term.
The other option we have are medication treatments. So you’ll have the treatments such as Ambien, Lunesta, Sonata, and we’ll also have Rozerem and for some patients we use Benzodiazopine/Clonazepam. Things like that to help with anxiety. Those are another option that we’ll use. Sometimes we’ll use them in combination with behavioral, sometimes alone. It really depends upon the patient.
Question: How do circadian rhythms affect our sleep patterns?
Shelby Harris: So when it comes to circadian rhythms, it’s a clock that’s basically programmed in our body. So if you think back to times when people lived on farms and we didn’t have electricity. People went to bed when the sun went down and they woke up when the sun came up. That’s what our bodies are naturally programmed to do. However, with all the new stresses in life with electricity, with technology, we tend to override that system and we’ll stay up later and we’ll get up earlier or later, and we use alarm clocks, we use the light. We haven’t really – it’s harder for us to set those rhythms. So it’s really important to keep a steady bedtime and wake time to really lock in those rhythms.
Now circadian rhythms become very interesting and problematic for patients because when you become a teenager, your rhythms actually tend to naturally shift. So someone who is a child usually goes to bed about 8:00 or 9:00 at night, but then when they have a circadian rhythm shift, it shifts later. And this is natural. And they start to go to bed at 11:00, 12:00, 1:00 and they want to sleep later. So we see this a lot in teens. And there’s a problem for them when they have to get up and go to school in the morning, they’re very sleepy, yet on the weekends, they’ll sleep 12 hours, they’ll sleep late and then go to bed late and wake up late. And on vacations, it’s not a problem.
So we don’t really treat it unless it’s actually a real problem for them in school. And then some patients actually find that this problem continues into adulthood. We’re not really sure why it continues, but when they become adults, we usually have to treat it because many people need to get up early to go to work and they can’t be sleeping until 11:00 or 12:00. So we use treatments like bright light therapy, melatonin, things like that that are very effective.
And then we have other opposite problems with circadian rhythms that can happen when you – a lot of times with older adults. They start to go to bed at 6:00, 7:00 at night and they wake up at 2:00 in the morning. And they’re rhythms actually shift earlier, but sometime it can just kind of miss the mark and shift too much earlier and that’s when we need to treat it with bright light.
And circadian rhythms come into play with shift work. So a lot of people who work rotating shifts and they work at night, their bodies are set to want to be awake during the day and sleep at night. So there are some people who have a lot of trouble adjusting their rhythms and they have trouble working the night shift, they’re sleepy, they’re drowsy driving home. And that’s when we need to look at as well and really treat it if it’s becoming a problem.
Question: Is it possible to live nocturnally and get enough sleep?
Shelby Harris: Yeah, there’s some people who just naturally do it better. It’s uncommon, but there are some people who just have a delayed circadian rhythm and they just – they sleep better during the day then they do at night. So they’ve – a lot of those people with delayed sleep phase disorder they start to work in bars, they work some of the late night shifts, they sort of adjust to doing it more and more as time goes on.
Question: What’s the best way to deal with jet lag?
Shelby Harris: All right, so jet lag depends on which direction you’re going and it can be a little complicated, but there are a few different treatments. So one would be if you’re going somewhere – sorry it’s hard to think about it. If you’re going somewhere East from here, generally what you want to do is you want to try to have your bed time earlier and earlier so what we’ll do is I’ll have someone adjust for a week or two by going to be 15 minutes earlier and getting up 15 minutes earlier every night. So that can be a really simple thing. Honestly, what we use a lot is melatonin. So we use lower dosages of melatonin, taking it at different times, depending upon where we are traveling and that can really help adjust the body’s rhythm to wherever you are going.
Question: How has our understanding of the function of dreams changed over the years?
Shelby Harris: Okay. So the older models, when you look at Freudian, when you look at Jungian thought, and there’s still people who really – who really use the Jungian thought of dream analysis, is really that you would analyze the dreams. The dreams are there for a purpose. For some people they say, it’s about wish fulfillment, it’s about the things you are never able to do in your day you are actually fulfilling at night. There are other people who will say that it’s actually telling you something. If there’s a lot of fear that’s going on, if there’s a lot of anxiety, it’s manifesting itself in your nocturnal world so that analyzing it can help open up basically thoughts about what you need to do during the day. So a lot of people who subscribe to the psychoanalysis, the Jungian thought will really focus a lot on dreams, the meaning, and how it can be used to help you during the day.
Now if you go to more modern thought, there are different – it’s actually quite a controversial area. There are some people who believe that dreams really are just kind of a throwaway thing. They are just a way of your brain processing what’s happening during the day, but there’s really no meaning to them; a lot of imagery of just flashes of what happened. There are other people that think that dreams actually do serve a purpose. But what that purpose is, we’re not really sure. So some people believe that it actually does have some psychological representation of what’s going on in the day, but there’s no need to sit and really analyze it. There are other people who think, like myself, that dreams are almost – they’re a reenactment of what happened during the day, but it’s a way of your figuring out and your brain processing, to figure out what does it need to hold onto and remember and what can it just throw away. So it’s like your brain has a large filing cabinet and it’s opening up each drawer and it’s taking in various images and memories from the day, consolidating what it needs to and puts in whatever file. And then if there’s something that doesn’t fit in any of the files and doesn’t really belong, you’ll forget about it. So it’s a way of really getting a succinct way of storing things in your brain.
Question: How are nightmares different than regular dreams?
Shelby Harris: So nightmares are distinctly different from dreams in the way that people feel them and experience them. So a lot of people think that a nightmare is something where something is chasing them and you have to wake up screaming. Yes, that’s one of the more common nightmares that we see is the person chasing someone or they’re being chased. But really, a nightmare just really has to evoke some sort of, we call it, dysphoric emotion or something uncomfortable. You could be sad, you could be unhappy; you could be scared, anxious. But traditionally, the definition is you have to awaken from this nightmare. So you have it, you awaken from it and you can recall, in detail, what just happened, that’s a nightmare. So it’s very different from a dream where you generally don’t wake up from it and you don’t have this dysphoric emotion.
There’s some debate as to whether you need to awaken from them because there are some patients who are actually starting to say, “I had these horrible nightmares, but I never woke up from them.” But they can still recall them when they get up in the morning. So there’s still some debate in the field.
When it comes to the reason why we have nightmares, we’re still debating that. It’s a new area of research, nightmares. And the way I like to think about it is, our brain – we have stress during the day and our brain needs to learn to process this stress. So there are people who have repetitive nightmares. And what happens is their brain is trying to process the stress and help their brain actually deal with what happens if this stress happens again, so their brain’s preparing them to deal with it in case the stress happens again, but it’s so scary that they awaken from it. So they’re never actually able to finish the file and put it away, it just keep happening because they awaken from it.
Question: How does IRT help one overcome nightmares?
Shelby Harris: So Image Rehearsal Therapy, or IRT, we’ll call it for now, it’s a very, very simple treatment that was developed by Barry Krakow in the late 90’s, early turn of the decade to really help change the imagery that you’re having at night. So we think of it as imagery during the day, seeing things, picturing things in your head, painting a picture is very similar to imagery at night. That’s what dreams are, nightmares; imagery in the night. So what we do is we take these very simple techniques by basically telling someone if they have a nightmare – so take someone who has a recurrent nightmare of being chased by someone. We’ll have them come in and we’ll say to them, “Okay, not take that nightmare, tell me what it is, but now I don’t want you to think about it anymore. Just take it almost like it’s on at piece of paper and throw it out. Change that nightmare anyway you want. You change a tiny bit of it; you can change the whole thing. It doesn’t matter.” And I’m not the one to tell them how to change it. It’s their dream that they’re making. “so change it anyway you want to make it – just it could be neutral, it can be positive, whatever.” So the person chasing them could be a very scary experience.
What they would do is for example, I had a patient yesterday who changed his nightmare from him being chased to actually having his two younger brothers chasing him around in his old apartment and they were playing. So just by still having the chasing element, but making it a fun, playful chase with two people he knew, made it a much different dream than the nightmare he was having.
So then what I had him do was to close his eyes and I had him picture the story of his brothers came in they started chasing him, his mom yelled at them to stop, then they stopped for a minute and then they kept running after each other. He pictured that whole story in his head into the picture and he could see what everyone was wearing, the smells he could tell, he could see the carpet, every detail. And once he took himself through that picture for about five minutes, practiced it morning and night, if you keep doing that it actually helps reduced the nightmare frequency because you’re getting control over your nightmare.
Question: Does the patient then have this new dream while they’re asleep?
Shelby Harris: For some patients, they’ll have that new dream, for others it just reduces the nightmare frequency. We don’t know why yet. But it’s such a simple technique because it gives you control over it, over the nightmare that it works – there have been studies that showed for upwards of 90% of patients who actually do this treatment actually report it getting better, the nightmare frequency.
Question: Are night terrors different from nightmares?
Shelby Harris: Night terrors are very different from nightmares. A lot of people will think they’re the same, but they’re really not. Night terrors – you want to look at the time of night when you’re having the problem. Night Terrors happen in deep sleep. Nightmares tend to happen in a lighter REM sleep. So, night terrors are in deep sleep, and they’re more common in kids, as are nightmares, but what happens in a night terror is like a flash – we think a flash of some image or something happens in the brain. We don’t really quite know what. And it usually ends up with the child screaming almost like screaming bloody murder. It’s very scary for the parents or whoever else is around. But it happens very fast and the child has no recollection of it. They tend to stare off into space when they’re screaming. You can’t really engage them at all. And the child will go right back to sleep afterwards and have no recollection of it in the morning, or very little recollection. Usually there’s no recollection. It’s more scary for the parents.
So in kids, what we think is happening in the brain, the way I like to think about it is, it’s almost like, you’re brain is going through all these stages of sleep and it’s developing in children so fast that it’s almost like you’re shifting gears in a car. And at some point, you actually stall out a little bit, and that’s kind of what happens during a night terror. They’re brain is shifting so fast that it stalls out, they have this episode, but then they go back to sleep and everything regulates itself.
Very common in kids, like I said, it tends to get better as you get older. Now there’s some night terrors that happen in adults. And if it starts as an adult and you’ve never had them before, then there might be other things that are happening; it might be anxiety, depression, stress. And that’s when you might have more of a thorough psychological evaluation. In kids we don’t generally attribute it to any psychological basis.
Question: What is sleep paralysis?
Shelby Harris: Sleep paralysis is something that is actually very common. Many people have it, I’ve had it myself. And what happens is, when you’re in that REM stage of sleep, your brain is very active. You’re dreaming your most during that stage, you’re mind, your eyes are moving, there’s a lot going on. It’s like fireworks going on in your brain. Now, what happens in the rest of your body, and this is an evolutionary function, is that your body has muscle atonia, meaning your muscles are basically turned off. You can’t work. So, you’re brain is active, your muscles can’t work.
Now for what happens in sleep paralysis is that some patients, and we’ll notice this earlier in the morning because you’re having more REM sleep then, will wake up in the middle of REM sleep. So, I know myself, I woke up once in the middle of REM sleep and I couldn’t move my muscles. And it was very scary. And it’s scary for anyone who has it because you’re mind is very active, your eyes are active, but nothing else is moving. So you have to give yourself a little while. You’ll come out of the REM sleep and you’re muscle will awaken and it’s find. It’s a totally normal thing to have.
Now, it can be indicative sometimes of other sleep disorders, so we’ll see that a lot in narcolepsies. Some patients will report that they have sleep paralysis. If we see sleep paralysis alone and nothing else, we don’t really think all that much of it, but if we see other symptoms, then it might be a red flag for something else that’s going on.
Question: What happens if our muscles aren’t paralyzed during REM sleep?
Shelby Harris: So REM Behavior Disorder, RBD. It’s newer diagnosis, I’d say probably about the past 10 or 15 years, we’re really recognizing it more and more. Patients will come to our practice and they’ll say, “I’m waking up in the morning and ****, I have bruising on my arms. My fists are bloody” or they’ll say, “My house was a mess. I found things all over the place.” Generally that could be sleep walking, but sleep walking tends to not be as violent. And that’s earlier in the night when you are in the deep stages of sleep. In RBD, it tends to be a bit more violent, a bit more aggressive. So when you are in REM sleep, you’re muscles are supposed to have atonia, and no function for them, but for some patients their muscles don’t turn off. So if they’re having nightmare or a very vivid dream, they’ll actually act out – essentially their dream in their sleep during REM sleep. So that’s why we’ll start to see patients come in with bruises, their bed’s a mess, they might fall out of bed, things like that. So it can be, for some patients, a very violent problem that we actually need to treat them aggressively.
Question: Have there been court cases in which RBD has been blamed?
Shelby Harris: Yeah. There are some that are – REM Behavior Disorder, we’ll see some court documented cases. And they really need to have a thorough evaluation with a sleep specialist. You can’t just say, “Oh, it was while I was sleeping.” There’s confusional arousals, there are states in deeper sleep that can happen where people will go and they’ll disappear and they’ll take on some other persona. They’ll commit some crime, but it’s all when they are in a very deep stage of sleep. So you really need to have a very thorough evaluation. But yes, there is a line of work of people who work with people who have been charged with crimes and we’ll actually do a sleep disorder analyses with them.
Question: What is narcolepsy?
Shelby Harris: So, narcolepsy is a disorder that affects many different areas of life. So in typical patients with narcolepsy, they have something called “excessive daytime sleepiness.” So, they’re very sleepy during the day. Yet, at night, they’re still sleepy, but their sleep is very broken. So we’ll see patients with narcolepsy, you’ll see the classic narcolepsy with cataplexy, as we call it. When patients will have – they’ll just fall asleep, right away. So, if there’s a loud noise, a strong emotion, happiness, anger, fear, can actually make their bodies shut down and have muscle weakness that they fall asleep. Other patients it’s not that severe. They’ll have a lot of muscle weakness.
I have one patient who used to hear a loud noise when she was at work and her right side of her face used to become numb and weak. So there are a lot of symptoms that happen with narcolepsy. We’re not fully – we’re starting to learn what’s causing it. There’s something in our bodies in our brain called hypocretin, and they’re seeing that people who have cataplexy, so that muscle weakness, those patients tend to have a lack of hypocretin and it decreases even more as they age. So we don’t really know why it’s happening, but that’s one theory as to what may be what’s going on.
Other things that happen in narcolepsy is they tend to have very vivid dreams. So when they do fall asleep, when they take those really brief naps that are very refreshing, so even a five minute nap is completely refreshing for these patients, but the minute they go into sleep, they dream and they have very vivid dreams during the day and night. More so then most patients do.
Now narcolepsy is really hard though because they’re very tired during the day, they’re sleepy during the day and it’s managed mostly with medications. So we use medications to help them sleep better at night and to stay away during the day. But there are behavioral things you can do also by changing diet, exercise, having an actual nap schedule. But it can be difficult because patients want to work. They want to have functional lives and to have a discussion with an employer about being able to take a quick nap, it’s refreshing for them to be more energetic during the day, it’s actually a real problem so sometimes we’ll have to work with employers to help them see that narcolepsy is a real diagnosis.
Families will often call patients lazy, so it’s really a disorder that affects not only the patient, but marriages, families, workplaces, it can really affect a lot of people.
Question: Did you see “Inception”?
Shelby Harris: I haven’t. I have a five-and-a-half month old at home, so I’ve barely seen any movies recently. But I’ve heard a lot about it, yeah.
Question: What have your colleagues thought about the movie?
Shelby Harris: It’s interesting. I haven’t heard a lot of colleagues who have seen it yet. But the few people I have, they – it’s an interesting movie. I think anything about sleep is interesting. It’s just what I do for a living, but there’s the notion that you can change your dreams, you can invade people’s dreams. I think it’s much more of a sci-fi futuristic way of thinking about it. But it does touch upon things that we can do nowadays. So if you really want to dream about something at night, if you think about it a lot and you have – you think about it right before you go to bed, you’re going to increase your chances of dreaming about it. So there are – it’s interesting in that it takes what we do and what we know to a much more extreme measure. And that’s what I kind of like about the theory behind it, about the movie.
A conversation with the sleep psychologist.
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It turns out, that tattoo ink can travel throughout your body and settle in lymph nodes.
In the slightly macabre experiment to find out where tattoo ink travels to in the body, French and German researchers recently used synchrotron X-ray fluorescence in four "inked" human cadavers — as well as one without. The results of their 2017 study? Some of the tattoo ink apparently settled in lymph nodes.
Image from the study.
As the authors explain in the study — they hail from Ludwig Maximilian University of Munich, the European Synchrotron Radiation Facility, and the German Federal Institute for Risk Assessment — it would have been unethical to test this on live animals since those creatures would not be able to give permission to be tattooed.
Because of the prevalence of tattoos these days, the researchers wanted to find out if the ink could be harmful in some way.
"The increasing prevalence of tattoos provoked safety concerns with respect to particle distribution and effects inside the human body," they write.
It works like this: Since lymph nodes filter lymph, which is the fluid that carries white blood cells throughout the body in an effort to fight infections that are encountered, that is where some of the ink particles collect.
Image by authors of the study.
Titanium dioxide appears to be the thing that travels. It's a white tattoo ink pigment that's mixed with other colors all the time to control shades.
The study's authors will keep working on this in the meantime.
“In future experiments we will also look into the pigment and heavy metal burden of other, more distant internal organs and tissues in order to track any possible bio-distribution of tattoo ink ingredients throughout the body. The outcome of these investigations not only will be helpful in the assessment of the health risks associated with tattooing but also in the judgment of other exposures such as, e.g., the entrance of TiO2 nanoparticles present in cosmetics at the site of damaged skin."
It's one of the most consistent patterns in the unviverse. What causes it?
- Spinning discs are everywhere – just look at our solar system, the rings of Saturn, and all the spiral galaxies in the universe.
- Spinning discs are the result of two things: The force of gravity and a phenomenon in physics called the conservation of angular momentum.
- Gravity brings matter together; the closer the matter gets, the more it accelerates – much like an ice skater who spins faster and faster the closer their arms get to their body. Then, this spinning cloud collapses due to up and down and diagonal collisions that cancel each other out until the only motion they have in common is the spin – and voila: A flat disc.
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