Dr. Guy Leschziner
Appearances
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, I've always been fascinated with sleep. Really, even as a schoolboy, I was fascinated with neuroscience and read the books of Oliver Sacks. And it was really reading those stories that got me fascinated by the world of neurology. And as an undergraduate, although historically in the UK and pretty much everywhere in the world, sleep has been very, very poorly taught.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
It's been largely ignored. But as an undergraduate, when I was at Oxford, I was asked to go away and write a thesis on why we dream. And what occurred to me at that point was, first of all, how little we knew about sleep and the fact that despite us doing this for eight hours a day, we have no real understanding of why we do what we do.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
It was a really fascinating area that subsequently has taken me into all sorts of areas of medicine because we now understand that sleep and sleep medicine, it has links with every aspect of human physiology and human medicine.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, it's staggering, really, if you think about it. If somebody were to ask you, well, why do we eat or why do we drink? And you turned around to them and said, well, you know, I don't know. It would be laughable. Yet this fundamental aspect of our lives is absolutely crucial to every aspect of our being. We really understand incredibly poorly.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
I think the answer is that there's no one function of sleep, that sleep has a multitude of functions. So we know that it is...
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
primarily controlled by the brain and many of its functions are for regulation of brain function of normal brain functioning so that sleep is part of the housekeeping that is required to maintain our brain which is a the most metabolically active organ in our bodies in in fighting shape
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
We know that sleep has important functions in terms of making connections between different cells within our brain, sometimes actually pruning those connections. But it's also involved in, for example, flushing out toxins or metabolites, substances that have built up over the course of the day out of our brains and back into the rest of our systems.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
But it goes well beyond the brain in that we now understand that sleep is absolutely vital for regulation of cardiovascular function, for kidney function, for healing and restoration of various aspects of our bodies, regulation of our immune system and so on. So an absolute array of functions. When we talk about sleep,
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Yes, that's absolutely right. I think that some of that is related to the fact that sleep is not a single state. So we often think of sleep and wake as being binary states. So either you're awake or either you're asleep. But actually what we know is that sleep consists of multiple different stages.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So at its most basic level, we divide sleep up into REM sleep or rapid eye movement sleep, where the brain appears to be very active when we monitor the activity of the brain using electrodes on the scalp. Actually, it looks rather similar to wake on that basis. And then non-REM sleep, which is where the brain activity slows down and becomes a little bit more quiescent.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
But even within those categories, we know that in non-REM sleep, which is the stage of sleep that we most associate with restorative sleep or sleep that makes you feel better when you wake up.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
There are different stages of sleep, and it seems that our experience of sleep, you know, how we subjectively feel our night has gone, sometimes bears relatively little relationship to the objective measurement of sleep that we can record when you come in for a sleep test in a sleep laboratory.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, I think on a population basis, we know that sleeping very little or sleeping a lot is associated with a range of negative health consequences, including mortality, the most negative health consequence. So people who sleep a very short period, usually less than about six hours, certainly have an increased risk of mortality compared to those who sleep seven or eight hours.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
But it's important to understand that that is on a population basis and that for each individual, what is seen as a normal sleep requirement is perhaps slightly different. And that's a function of the quality of your sleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So whether or not you've got anything else going on with your sleep, like, for example, sleep apnea, this breathing condition that disrupts the quality of your sleep because your airway is constantly collapsing. But it's also a function of your genes in that we know that there are a number of genes that influence our sleep requirements.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So, for example, I have a few families that I've seen in whom everybody in that family sleeps a very short duration and doesn't seem to have any negative effects of sleeping, say, four or five hours a night.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
But it's also important to understand that some people are resistant to the effects of sleep deprivation in terms of how sleepy they feel, but not necessarily resistant to the effects of sleep deprivation in terms of, for example, their cognitive function, how easy they find to perform particular tasks or how good their memory is, for example.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So just because you don't necessarily feel sleepy when you're sleep deprived doesn't mean that you don't have any consequences of that sleep disruption per se.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, the evidence suggests that if you sustain a significant sleep debt, which is how we term it, that if you're losing quite a lot of sleep during the week, then actually it's quite difficult to make that up by lying in at the weekend and that some of those cognitive effects of being sleep deprived during the week persist on a Monday morning.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So the answer to that is if you really are burning the candle at both ends, then actually catching up at the weekend is very difficult.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Yeah, sleep hygiene is a horrible term. It really conjures up images of, you know, sleeping in a dirty bed. Essentially, what we mean by sleep hygiene, as you say, is those behaviors that are conducive to a good night's sleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
And some of those are really obvious, you know, like not drinking several cups of coffee before you go to bed, not smoking immediately before you go to bed or consuming other nicotine containing substances, sleeping in a quiet environment. Some of them are becoming increasingly well known. like avoiding bright light in the evening.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So there is some evidence to suggest that what we do by exposing ourselves to bright light in the evenings is suppress our natural secretion of melatonin. So melatonin is this substance that an area of the brain called the pineal gland puts out that that is the chemical signal to the brain and indeed the rest of the body that it's time to go to sleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So by exposing yourself to bright light in the evenings, what you may actually be doing is having a negative effect both on sleep quality, but also making it more difficult for you to get off to sleep in the first instance.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
We know that one of the major causes of difficulty sleeping, insomnia, is actually a condition called psychophysiological insomnia, where psychological factors...
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
um largely surrounding your association your conscious and unconscious association with being in the bed and drifting off to sleep are replaced by negative associations so rather than associating bed with being a comfortable sleeping environment where you feel cozy and you feel the warmth of and the security of knowing that you're going to drift off to sleep it's replaced by
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
that stress, that agitation, that anxiety that you're actually not going to drift off to sleep and that you're going to lie there awake for prolonged periods of time.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So rather than the bed being an inviting place of comfort, it often gets that psychological association is replaced by a feeling that your bed is an instrument of torture, that it's the place where you go to where you will have difficulties dropping off to sleep and will stay awake for a prolonged period of time.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
And for many people, it's addressing those psychological factors that is actually the solution to actually treating their insomnia. For other people, however, there are many biological factors that result in poor sleep, be that medication that you're prescribed for something else, be it a range of sleep disorders like obstructive sleep apnea or a condition called restless leg syndrome.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So there are many different reasons, but we know that by far the commonest is insomnia, which affects about one in three adults at some point every year and about one in 10 adults on a regular long-term basis.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, that's just normal. That's a normal response to what's going on in your life. I think that one of the things that's under appreciated is that the range of normal when it comes to sleep is actually quite large. And just because you have a few nights where you don't sleep particularly well, that doesn't constitute insomnia. It doesn't constitute an ailment. It is part of normal life.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
You know, people don't appreciate that caffeine hangs around for a very long time, particularly if you consume a lot of it. People, especially nowadays, are very used to using gadgets, you know, their cell phones or laptops in bed. And that's not very conducive, firstly, because of the issue of light exposure. But secondly, also, that's quite a mentally stimulating activity.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
You know, one of the issues is that there are a range of sleep disorders that are very poorly known about, not just by the general population, but also by physicians. And in many cases, we often see individuals who clearly have had a problem with a sleep disorder for many years that has gone unrecognized.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So it's knowing about these sleep disorders, recognizing them as sleep disorders, that is really the first step to getting appropriate treatment.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Both, really, because the psychological and the physical interact quite a lot. There are some sleep disorders that are clearly purely biological. Things like obstructive sleep apnea, which is people who are snoring and collapsing their airway in the middle of the night. Things like restless leg syndrome, which is physical.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Things like narcolepsy, which is a very pure neurological disorder that results in
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
damage to a very small part of the brain but for some individuals there are sleep disorders that have inputs from both so for example people who sleepwalk we know that actually the basis of sleepwalking is purely biological it's as a result of different parts of the brain being asleep whilst other parts of the brain are awake but obviously
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Those events can be influenced by daytime stress, sleep deprivation, poor sleep hygiene. So this is a good example of an interaction of the psychological and the behavioral and the environmental and the physical.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Well, I think I mentioned at the start of this interview that one of the essays that I was sent off to write was, why do we dream? And I'm not sure that we have any better inkling now than when I was writing that essay over 25 years ago. I think we know that dreaming probably has more than one function, and it probably has different functions at different stages of our lives.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So there are lots of theories, but none have been definitively proven. One of the theories is that dreaming is absolutely crucial to the development of consciousness in early life, so what differentiates us from other animals. But it also appears that dreaming is of significant importance in terms of memory, in terms of emotional processing, in terms of learning something about our environment.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
And one of the popular theories about dreaming is that actually it creates a virtual environment in which we can tweak our model of the world around us so that we're integrating the sum of all our past experiences to tweak what we understand about the world around us.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
I think to argue that it predicts the future is very difficult from a scientific rationalist perspective. But certainly there is some evidence that REM is linked to creativity. So REM sleep being the stage of sleep that we most associate with dreaming. You know, there are many, many examples of people who have dreamt particular songs or particular works of literature.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
You know, I think it was Paul McCartney in Yesterday is often... It's often used as an example of that he said that came to him in a dream. So, you know, clearly there is potentially something in the fact that REM is about creating links between different parts of the brain which facilitates creativity.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
I think that has largely fallen away as a popular idea in the world of neuroscience.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Yes, the brain is a creature of habit. And, you know, sleep is a learned habit and as such can be unlearned. I think the exception to that is that occasionally I see people who have become so obsessed by their sleep that they actually, if they don't meet that rigid schedule, they become very, very stressed and then don't sleep at all as a result.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
So there is a line to be trodden balancing your sleep
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
It is important to stress that we all within our brains have a clock. We have a circadian rhythm. There's a part of the brain called the suprachiasmatic nucleus that regulates our circadian rhythms throughout our bodies. It's also important to understand that sleep, as I said, is not a continuous state. So people are constantly having brief awakenings or having very, very light sleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
And so it's quite possible that there are some circuits within the brain that maintain a degree of awareness or a degree of consciousness. In fact, that's what we think is happening during lucid dreaming, which is when people have an awareness of the fact that they're in a dream and can actually sometimes exert conscious control over their dream.
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How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
These are networks that are responsible for consciousness that are firing during our dreaming sleep and they probably fire in different stages of sleep as well. So, you know, to think of the brain as being switched off during sleep is quite incorrect.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
The answer to that is mixed. The difficulty that I have with sleep trackers is that, first of all, they sometimes engender a degree of obsessionality about sleep. But also people may be drawing very wrong conclusions about the nature of their sleep in that we know that sleep trackers do have issues in terms of their accuracy. They're good at telling us how long we spend in bed.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
They're okay at telling us how much sleep we get, but they're not very good at telling us what stages of sleep we're in. And people often become quite obsessed about the fact that they're not getting as much deep sleep as they feel they should or that their sleep tracker shows that they're waking up multiple times a night. And that can actually drive the insomnia and can make things worse.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
And actually, when you talk to people with significant insomnia, they will often say, you know, when I'm sitting on the sofa watching television or listening to music or reading a book, I will doze off. And once I get into bed, I find it incredibly difficult. So it's when they're not thinking about the process of going to sleep, when they're not in bed thinking about sleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
that they're actually far more able to fall asleep.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
Okay. Bye-bye.
Something You Should Know
How We Play: They Story of Fun and Games & The Cost of Not Sleeping Well
We know that sleeping very little is associated with a range of negative health consequences, including mortality. People who sleep a very short period certainly have an increased risk of mortality compared to those who sleep seven or eight hours.