We're in the middle of a sleep crisis.
A third of us regularly struggle with our sleep,
which rose to one in two during the pandemic.
The highest it's ever been.
I'm Michael Mosley, and I have suffered from sleep
problems for many years.
The good news is as more and more of us seek help,
new advances are revolutionising our understanding of sleep.
We are now able to capture brain waves of people
while they're asleep in their own home.
Unlocking the secrets of the sleeping brain,
which could help solve our nightly struggles with insomnia.
I slept for ten hours - ten hours!
Seriously, that never happens.
Sleeping better can also transform our health, from staving off
life-threatening diseases...
Amyloid is a protein that's implicated in Alzheimer's disease.
When you're asleep, amyloid is removed from the brain
at very high rates.
..to reducing the sugar cravings caused by missing out on sleep...
On average, people consume 385 calories more per day.
Oh, wow, wow.
..and even improving our mental health...
REM sleep is where most of our vivid dreams occur,
and it's important for our emotional regulation.
I'll find out if my poor sleep is impacting my health...
It's bad for you because, if it's extensive, that could lead
to cell death.
..and I'll see if brand-new tech can help.
So instead of relying on drugs,
you're using technology to try and improve the quality of your sleep.
I'm hoping the latest science can help me, and millions like me,
learn how to sleep well.
Didn't really think this one through before I did it.
A good night's sleep is a wonderful thing.
I just wish I had more of them.
For years, I've struggled with insomnia,
waking up in the middle of the night
and finding it hard to get back to sleep.
How did you sleep?
I slept like a log. Lucky old you...
I only woke up when you were marching around the bedroom.
When I'm awake at 3am, I'm normally thinking, "Well, here we go again."
I don't think I've slept through the night for probably
a decade, maybe longer.
To explore the extent of the current sleep crisis, I've teamed up
with the University of Oxford to launch a landmark census
of the nation's sleeping habits.
Right, let's give it a go.
OK, so, "How satisfied are you with your current sleep pattern?"
Not terribly!
"How often do you use alcohol or prescription medicines
"to help go to sleep?"
Filling in the census provides instant feedback on the quality
of your sleep - rated from one to ten.
Anything below five is a sign of poor sleep.
"Thank you. Your score is 2.8."
That's not great, is it?
I hope there aren't too many others doing as badly as me.
BELL RINGS
I'm in Oxford, City of Dreaming Spires,
and home to one of the world's leading sleep research centres.
It's here that all the data from our census is being analysed.
Leading the team are Professor Colin Espie and Dr Rachel Sharman.
What can you tell me? What did we find?
We're sat at 207,000 people... Woohoo! Wow!
..which is fantastic.
It just shows how popular the topic was.
What were the most interesting findings
as far as you were concerned?
The average sleep in the UK in 207,000 people
is six hours, 48 minutes.
Wow, that's shorter than I was expecting.
Shorter than I would like.
The recommended sleep for an adult
is somewhere between seven and nine hours,
but to average lower than seven hours is a bit of a worry.
Some people not getting enough sleep because they're not giving
themselves enough opportunity to sleep,
but there's other people in there who would desperately
want to sleep, and they can't cos they've got insomnia.
As well as all those struggling to get the recommended
seven to nine hours,
there's a second, alarming pattern in the data.
When it came to sleep quality,
almost half reported having poor sleep.
About 44% were showing signs
of having poor quality sleep,
which I think is slightly more than what we'd expect. Yeah.
And what we mean by poor quality of sleep is maybe a struggle to get
to sleep or a struggle to get back to sleep, feeling unrefreshed,
feeling it's affecting your day time.
And it is higher than we would expect.
I may complain, but I don't actually think my sleep is that poor quality.
Even though I wake up in the middle of the night,
I try to make sure I get enough.
I usually manage to get at least seven hours' sleep a night,
but I almost never sleep throughout the night, so I'm very keen to find
out more about what goes on when I'm sleeping.
To find out what's really going on in my brain when I'm asleep,
Rachel, from the Oxford team, has brought along an impressive
new piece of sleep science kit.
This is a really exciting time for sleep science.
We are now able to move out of the lab
and actually capture brain waves of people
while they're asleep in their own home.
I'm impressed.
This home sleep test is a miniaturised, portable EEG machine,
designed to record the brain's electrical activity during sleep.
But not all sleep is the same.
In fact, it involves four distinct stages,
and scientists are learning more than ever before
about how they are crucial for our mental and physical health.
Each stage of sleep can be identified by its pattern
of brain waves.
I obviously spend an awful lot of time watching people sleep
and analysing sleep,
and I'm still in absolute awe of what our brain does.
When we're awake, our brain waves are short and fast.
As we drift off into the first stage of sleep,
they begin to slow down.
In this first stage, we're transitioning from the chaotic,
fast activity to this drifting activity where the eyes are rolling
and the head is nodding.
Next is stage two, which looks very similar to stage one,
except for little bursts of activity.
This is preparing the brain for learning and memory that occurs
in the later stages of sleep.
The third stage is deep sleep,
where we see a more
spaced out pattern
of taller waves known as slow waves.
It's this deep stage of sleep that is really important
for our physiological repair,
and it's also really important for our memory.
Getting plenty of this deep, slow wave sleep also helps improve
the immune system and our ability to fight infections.
Everything is kind of coordinating, is it? Exactly.
It's beautiful. It's almost like the brain is pulsing.
Finally, we enter stage four, REM,
where our brain waves return to a shorter and faster pattern,
similar to when we're awake.
Our bodies are paralysed,
but our eyes move rapidly while we dream.
REM sleep is where most of our vivid dreams occur, and it's important
for our emotional regulation.
It's really important to not only just get enough sleep in terms
of duration, but getting enough of these individual stages.
Rachel has a chart called a hypnogram to show me how,
in a typical eight-hour sleep,
the four stages are repeated several times
in what are known as sleep cycles.
We have yellow, which is stage one,
green, which is stage two.
and this blue colour, which is stage three.
And then we have red up here,
which is our REM sleep.
So it's making sure that we've got enough of each stage
of sleep of optimal functioning.
OK, so this is the bit of kit you want me to use? Yes, please.
Right, OK. Good look? Do we like that?
Definitely. MICHAEL LAUGHS
I feel deeply honoured
because I'm the first person to use this device outside the Oxford lab.
Rachel would use the data to map out not just how much sleep I get,
but crucially, how much of each stage of sleep.
I'm especially curious to know how I score on deep sleep.
Hi, Rachel. Hi, Michael. Good to see you.
Results time. Results time, exactly.
Here is your hypnogram, which is the first time
we've recorded this in the wild, in your home.
Yay! So I'm number one, am I?
Participant One!
By bringing the Sleep Lab into the home environment,
these devices are going to revolutionise our field.
Before we get onto my deep sleep,
the device has revealed something alarming.
I didn't just wake up once, but multiple times in the night.
You were in bed for eight hours and 21 minutes,
but actually, when we add up all of these awakenings
that you've had, you're only spending 75% of the time
in bed asleep.
That means a quarter of the time I'm in bed, I'm awake. Exactly.
Anything over about 30 minutes awake in the night is problematic,
and you're up here at one hour and 43.
I can actually show you...
The tablet was actually picking up audio during the night.
So one of the reasons I think you were coming in and out
is because you were snoring.
LOW RUMBLE That's me snoring, isn't it?
That is you snoring.
Some of them were right up there at 45 decibels.
So, that would be enough to wake me up
or possibly Claire nudging me and going, "You're snoring."
All too often, these awakenings are preventing me from reaching
the stage of deep sleep.
We need our deep sleep to detoxify the brain.
It is our brain's laundry system.
It flushes out all those toxins that have built up.
You want to have about 20% of your lights off to lights on
in that deep sleep.
Over those eight hours, you only had about 12%. Right.
Is this kind of typical for a 64 or bad for a 64?
It's not great for a 64-year-old.
Rachel is certainly not mincing her words.
You're not sleeping enough, and if we're not sleeping enough,
we're putting ourselves at higher risk of all sorts of nasty things
like cardiovascular disease, metabolic dysfunction,
and even cancer.
It's very clear that I have insomnia.
I'm not getting enough sleep,
particularly of that sort of beautiful, slow wave sleep.
To find out in more detail how poor sleep
is impacting our underlying health,
I'm taking part in ground-breaking research
at the University of Surrey.
I'm about to do a remarkable new test which looks at genetic markers
in my blood and which, apparently, can tell the impact
that lack of sleep has on things like stress,
my immunity, and my risk of disease.
Unfortunately, it also means I have to have blood taken before
and after a completely sleepless night.
Right, so, Claire, my wife, is taking my blood.
Fortunately, she's a GP, so this is not just amateur hour.
Playing at home. Just playing at home, exactly. Playing doctors.
As well as blood tests, which will measure genetic markers,
I'm going to find out how well I cope with the immediate aftermath
of lost sleep.
I think I'm pretty good at getting by,
but what's the reality?
OK, done.
DOORBELL RINGS
It's bright and early, and I've got a lovely delivery here,
which is full of goodies.
To see how well I really cope,
Rachel's sent me a selection of tests.
I'll be tackling puzzles that measure my reaction times
and mental clarity,
and others that will assess my concentration
and ability to perform physical tasks,
while monitoring the number of mistakes I make.
LOUD BUZZER Ah!
And, finally, with the help of my daughter Kate, I will find out
what a lack of sleep does to my pain threshold.
The idea is I have to try and keep my hand in there for as long
as possible, and you have to time it.
Three, two, one, go!
Right, oh, that was cold.
That is cold.
That is really very painful indeed.
OK, that was it. That was it?!
That was as much as I could do.
He only made it 32 seconds,
but from the sounds of it, it was very painful,
so I'm curious how he's going to do when he's sleep-deprived.
It's now time for a sleepless night.
Uh, and yeah, everyone else is going to head off to bed
and I'm going to stay here with Terry.
I think Terry's already keeled over for the night.
My in-built 24 hour body clock
is telling me that it's time for sleep...
..but by pulling an all nighter,
I'm messing with my body's natural rhythms.
One of the immediate effects is that I'm hungry
at an unusual time.
One of the worst things about being wake in the middle
of the night is the munchies.
I've been having a bit of a wander around looking for something to eat.
By staying up all night, I'm missing out on all the benefits that come
with the four stages of sleep.
Finally, my long, sleepless night is over.
There's something very primal
about having survived a night
and being out here in the dawn.
But how will missing all those crucial stages of sleep affect me?
How am I feeling?
I'm sort of feeling relieved.
I didn't really think this one through before I did it.
It's now 9am
and I actually feel like my usual coping mechanisms are working well.
Research suggests it's possible to experience brief feelings
of euphoria when sleep deprived,
although we don't really know what's happening in the brain
that causes this.
What's interesting to me is at the moment I'm beginning
to go gabble, gabble, gabble.
An area of the brain that's particularly sensitive to lack
of sleep is the prefrontal cortex,
the part that does a lot of planning and decision-making.
BUZZER
I think I need to slow down
and be a bit more careful.
Ah! Oo!
Research also shows our perception of pain is heightened
when we miss out on deep sleep,
something I'm definitely experiencing.
Ah!
That was bad.
Blimey! Must be wrong.
According to this, I only lasted 18 seconds this time,
which is truly pathetic.
By mid-afternoon, I'm suffering from brain fog
and feeling irritated by the tests.
Right...
Our sleep centres also linked our poor sleepers
with lower mood scores...
..which isn't surprising, as by staying awake all night,
I missed out on the crucial REM stage of sleep,
which plays an important role in regulating mood.
How did you find it?
I was conscious that I felt grumpier,
but I thought that I was actually doing quite well in these tests,
and clearly, some of them, I wasn't.
This is the buzz wire,
and this is where you had to move the little loop through the wire.
The number of mistakes I made
more than doubled when I'd missed out on sleep.
I was rushing the buzz wire test,
being more careless.
And on the reaction time test, I was much slower.
Rachel's got a surprising explanation...
I was having tiny micro sleeps without even noticing.
This is your lapses,
so this is how many times you stopped paying attention.
What we can see here, in the green,
is you're getting worse overnight.
Both during the night and during
some of the tests in the morning,
my brain was desperately trying
to force me to nod off
to initiate the sleep cycle.
You're getting tiny bits of sleep coming in as your head nods
and you wake back up,
and these are sort of micro sleeps.
These are 500 milliseconds, so they're not long at all,
but it was enough for you to miss the signal that we presented.
What's important is you didn't even know you were having those lapses
in attention. It's quite scary, absolutely. Mm-hm.
Being awake after sleep deprivation
is similar in terms of performance
to having a blood alcohol level of about two or three pints.
You wouldn't drink and drive. No.
So, what about drowsy driving?
Alarmingly, as many as one in three of us admit to having experienced
micro sleeps while driving.
It's clear that being sleep deprived has a much bigger impact
on my mental and physical performance than I realised.
But what will the blood tests I did earlier reveal?
Hi, Michael Mosley. Just push the door. Thank you.
Professor Simon Archer, who pioneered this new test,
has been looking at thousands of my genes...
..and, remarkably enough,
just by looking at which genes were switched on
and which were switched off,
he was able to tell which blood sample was taken
after my sleepless night.
We knew that we had two pairs of samples - A, B, C, D.
We were very confident
from the beginning that sample D
was the sample taken
after you'd missed a night of sleep.
What this is telling us,
this big difference with sample D,
is that you staying up all night
has had a big effect on the gene expression within your blood cells.
Yeah. Big enough that we can clearly see it.
Most of the effects of the sleep deprivation are causing genes
to be switched on that wouldn't normally be.
We have genes that we know respond to stress.
Yeah. OK.
And these have all been upregulated in your blood. Right.
Essentially switched on? Yep.
So, I'm more stressed.
Losing sleep for just one night
prompted my immune system
to move into overdrive.
If your immune system is in overdrive when it shouldn't be,
that's not a good thing.
It's bad for you because you haven't got pathogens
that you need to respond to.
Simon also noticed that the energy-producing parts of my cells,
the mitochondria, were not functioning as they should,
which is a potential red flag for Alzheimer's.
The brain is a very active organ, it uses up most of your oxygen,
and it needs a lot of energy,
and the mitochondria provide that energy.
So, this downregulation will mean there will be a lack of energy
within those neurons. Right.
And this downregulation in mitochondria is similar
to the mitochondrial dysfunction
that's associated with Alzheimer's.
If it's extensive, that could lead to cell death.
The problem comes when people are frequently missing sleep
and the accumulation of those negative effects
and how that associates with health problems.
Very impressive - the fact that he could look at a sample
of my blood and tell whether I had been sleep deprived or not.
And, on a personal level, I did find it very, very striking
because, obviously, you hear all the stuff about lack of sleep
and what it might do to you,
but knowing what it actually has done to me
was very shocking, genuinely shocking.
The fact that it's increased my stress levels, had a bad effect
on my immune system, and quite possibly increased my risk
of Alzheimer's, albeit by a small amount.
All of that is something which really I find quite disturbing.
So, it's given me a lot to think about.
I'm now 64,
and my dad died prematurely at the age of 74,
and before he died,
he was showing signs of early sort of cognitive decline,
memory loss and things like that.
So, that's something I'll fear,
that that's what's going to happen to me, as well.
It's not just brain degeneration like Alzheimer's that's a concern.
Lack of sleep really does affect almost every system in your body.
In our sleep census, almost two thirds of those who are classed
as poor sleepers reported at least one mental
or physical health problem.
And there is one sleep disorder which, if left untreated,
can be life-threatening
and which millions of people suffer from without realising.
It's called sleep apnoea.
At the Royal Free Hospital in London,
security supervisor Kevin is seeing Dr Swapna Mandal
to confirm whether or not he has sleep apnoea.
I think sleep apnoea is more common than we realise
and definitely underdiagnosed.
In the UK alone, 1.5 million individuals
may have obstructive sleep apnoea
and only 20% of those have been diagnosed.
I have occasions where I'll wake up and...
..sometimes you just find it hard to breathe.
LOUD SNORING
It's like you have no air going through you.
You wake up and there's the taste of vomit in the back of your throat,
and it's hard to get rid of.
SNORING
Kevin's repeated waking results in broken sleep cycles
throughout the night.
If this is sleep apnoea,
it could put him at increased risk of heart disease,
hypertension and stroke.
My wife nudges me if I stop breathing.
I don't notice it.
It's just something that she noticed,
and that's how it all came about,
after being given an ultimatum - doctors or divorce.
She's happy about it,
the fact that it is the first stage
of hopefully getting something done.
GUTTURAL SNORING
The awakenings are usually so brief that the sleeper
doesn't notice them happening.
Patient goes to sleep and often the muscles in the upper part
of the airway relax and cause narrowing of the airway
and sometimes complete closure.
And that means the patient has a pause in their breathing,
which can lead to a drop in their oxygen levels.
But more importantly, it means that they often go from a deeper
stage of sleep to a lighter stage of sleep,
and so have disrupted sleep throughout the night.
Why don't you tell me a little bit about the symptoms you've had?
Last week it happened.
I woke up, literally gagging for breath - could not breathe.
We need to do a sleep study.
It's this little device here that sits at the bottom of the neck.
Keep it on the whole night and then we'll have the results.
When I first started,
patients would have belts around the chest and tummy,
tubing up the nose, a finger probe to measure their oxygen saturations,
and then we would have to review all of that data overnight.
Now, newer devices can give you an automatic diagnosis.
As Kevin sleeps, the device will capture sounds
from his breathing and his heart activity.
LOUD SNORING
During the test,
Kevin's breathing stopped on average 51 times every hour,
confirming he's got sleep apnoea
and it's severe.
So, to help with his breathing and reduce his risk of serious health
consequences, Kevin will try sleeping wearing a piece of kit
known as a continuous positive airway pressure machine.
A patient wears a mask overnight
that's attached to some tubing,
and it blows some gentle air pressure into the airway
to keep the airway open.
I now have this little baby.
It sends all the information via the Wi-Fi.
It's interesting
to know that someone else is sort of watching
and keeping an eye on how you're doing.
Kevin will wear the device for the next few weeks
to see if it radically improves his and his wife's nights.
As we're learning, a lack of sleep can impact us in ways
we are not even aware of.
For example, not getting enough
can significantly increase how much we eat.
And I don't just mean the odd attack of the midnight munchies.
Our census found that around 60% of poor sleepers had a BMI
that was in the obese or overweight category.
Dr Wendy Hall is a nutritional scientist
from King's College London,
who has been studying whether improving sleep
can also improve our diet.
Hello. Hello.
Good parky day. Yes!
What's the link between sleep and weight gain?
We know that short sleep can affect what we eat.
There's a part of the brain called the hypothalamus
that's very important for regulating lots of things in the body,
but one of them is appetite.
So, there are hormones that are produced in the body
that then send signals that act on the hypothalamus to tell the body
how hungry or full they should be feeling.
One of these is called leptin,
and leptin is a hormone produced by fat cells in the body.
So, when you get more fat stores in the body,
leptin levels go up,
and it's telling the brain that fat stores are sufficient.
But there's some evidence to show that people who are short sleepers
have lower levels of leptin.
There's another hormone that's important as well,
and this is more of a hunger hormone and it's called ghrelin.
It will go up when you're hungry, if you've not eaten for a while,
and there's some evidence that ghrelin levels are higher
in people who are short sleepers,
so they may be getting a constant hunger signal.
I certainly find that when I'm sleep deprived, what I crave madly
is sugary, fatty things like biscuits or croissants.
I think a lot of people would recognise that feeling.
So how much more do we eat after a bad night's sleep?
We did a study that pulled lots of other studies that had got
people in a metabolic unit and deprived them of sleep.
And, on average, they consumed 385 calories more per day.
Oh, wow. Wow.
It's about 20% of the average woman's energy requirements,
so that is a considerable amount, and it would lead to weight gain,
if that was continued over time.
These findings prompted Wendy and her team to try and help
short sleepers improve their sleep and, in turn, their health.
Sian, a nursing lecturer, is classed as a short sleeper.
On average, she gets less than six hours a night.
I've got into bad habits with sleeping,
and so I'm awake till 1:00, 1:30,
just doing nothing of any consequence.
And I know that when I'm staying up late at night, I'm snacking late
at night and eating things before I go to bed.
We have a long family history of type two diabetes.
My mother had type two diabetes,
my father did, my sister does.
It can reduce your life expectancy.
You know, and I have a lovely daughter,
I want to be fit and healthy for her as long as I can.
The team want to see if they can help her increase her sleep.
To do this,
they've asked her to make some fairly simple changes.
She'll try to improve her sleep routine by decluttering her room
and avoiding screen use late at night.
She'll keep up with good habits,
like getting out into the morning light,
which can help reset the body clock,
as part of establishing a healthier sleeping pattern.
The hope is this will not only help Sian sleep well,
but also reduce her calorie intake.
If you could just step on for me with your heels right at the back.
Thank you.
I think this will probably give me the push that I need,
whether it helps me lose a bit of weight, whether I feel better
during the day, and whether it just makes me that little bit
healthier, really.
Improving our sleep doesn't just make us healthier,
it can also boost our brainpower.
At the University of California in Los Angeles,
neuroscientists are investigating the link between sleep and memory
by studying how the brain tackles puzzles.
At the forefront of this research is Professor Gina Poe,
who has a particular passion.
I'm interested in mazes, because it's a task that engages
a good portion of your brain, including a learning and memory
structure that also maps your environment.
Today, I'm going to be Gina's guinea pig.
She's sent me to Blenheim Palace -
home to one of the largest hedge mazes on the planet.
She has sent me a video which will explain all.
Hi, Michael.
I've sent you to this maze to run it as fast as you can
and time yourself, and we'll see how you do.
And then after you've finished, I would love you to go home and get
a good night's sleep and then try it again in the morning
to see if you can run it any faster.
Well, that's pretty clear.
All I've got to do now is check the time and then head off
and see if I can conquer the maze.
Right.
Hmm, that makes no sense at all.
This is a dead end as well.
We need sleep to connect things that we cannot see when we're awake.
For example, when you turn left and you run into a wall,
and then you turn right and you run into a wall,
and then you go straight and you can go forward.
Those things aren't happening simultaneously,
and because they're not happening simultaneously, it's hard for us
to put all of that together.
This looks familiar.
Gina's work suggests that as I make my way through the maze,
a part of my brain called the locus coeruleus
is helping to identify information that will be processed when I sleep.
Locus coeruleus is a tiny area in the brainstem,
and it provides norepinephrine -
which is like adrenaline, but for the brain -
to the entire brain.
So when it's active, it's providing this juice to help us learn
more quickly from anything that's happening at the time.
I have a terrible feeling I've come to the entrance again.
HE LAUGHS
I HAVE come to the entrance again!
We are studying how these locus coeruleus neurons are firing
during wakefulness to tag memories for...
..reconsolidation during sleep.
Ah-ha.
So I need to go there.
I need to go there...
Ta-da!
Hooray!
Ah! And there we go -
29 and a half minutes.
I'm not sure if that's good or bad. I suspect that's bad.
Hi, Gina. Hello. Hi, Michael.
I've done the task and it took me nearly half an hour.
Well, I want to ask you, do you feel like you have a mental map
of the maze yet in your mind, or...?
It's pretty hazy, I have to say.
Get a good night's sleep and in the morning,
when you wake up, just try it again
and see if it's a little less frustrating this time.
OK. That'll be fascinating
because, at the moment, I feel I haven't a clue.
Ta-ra, then. See you. Bye-bye.
It's about 8:30 in the morning, so I'm feeling reasonably perky.
But the interesting thing will be, do I do the maze any better now
than I did yesterday. Right!
At first, the maze is as puzzling as before.
No. Right.
But as I get going, it feels easier than my first attempt.
Right, this is the first bit,
so I've managed to get here in a surprisingly short period of time.
And then round here. Yep.
Gina's research suggests that my improved performance
is down to what happened in my brain during specific parts
of my sleep cycle.
Thanks to deep sleep and REM sleep,
I was able to dredge up memories from yesterday
that I wasn't even aware of at the time.
There's a brief period of time during slow-wave sleep called
the transition to REM sleep, and it's where the hippocampus
is really well connected.
The hippocampus is our temporary learning and memory structure,
and it seems to be writing those temporary memories
to the long-term memory storage.
And it's only during rapid eye movement sleep that
we can selectively disengage pieces of memory.
So it's a time when you can actually both write new memories in
as well as erase pieces of memories
that you need to erase, or weaken connections,
and we can wire together the proper pattern,
the proper synaptic pattern
that is associated with solving the problem,
with finding a solution.
Uh-huh.
Good.
And...I remember going down that one before,
which was a mistake.
And if I am right, I go round the corner, and ta-ra,
I see Hermes - and indeed I do! Hello, old friend.
Really delighted to see you again.
I reckon that is just over six minutes
which, compared to half an hour the first time,
is obviously a huge, huge difference.
And there were interesting moments in there where I really didn't know
where I was, but there were other moments
where the sort of memories flashed back in.
Since good sleep is crucial for memory and problem solving,
it's perhaps not surprising that disrupted nights can play havoc
with our mental processes.
In the UK, over five million adults are believed
to suffer from insomnia.
One of them is campaigns coordinator Valerie,
who has a sleep score of just 2.5 out of ten.
Valerie's problem, just like mine,
is not in getting to sleep, but staying asleep.
It's called maintenance insomnia,
which means she may not be getting enough deep sleep and REM sleep -
stages of sleep that are crucial for memory.
I just feel like I do sometimes have brain fog,
so I do sometimes forget the simplest words.
I can have no memory of an event that I was at.
I mean, I'm working full-time, and I do have to make a lot of notes
if people are talking because otherwise it's just gone.
On average, Valerie gets between four and six hours
of broken sleep each night.
She can often be awake for hours at a time.
I'm not in a happy place.
I've been awake for a while.
I've not been asleep that long.
I'd probably say about a couple of hours or so.
It's Sunday night, Monday morning, and I'm wiped out.
Valerie has struggled with poor sleep and its side effects
since she was a teenager.
I just feel like I've never really been as focused as I can be
because I'm not rested, but I just feel like I probably
haven't maybe pushed myself for many things
because I feel like I can't achieve it because the focus is not there.
Seeking answers, Valerie's meeting Colin Espie
from the Oxford University team.
He wants to change the way she thinks about her sleep.
Hi, Valerie, it's so nice to meet you. You, too.
So I'm going to suggest something
that we call the quarter-of-an-hour rule.
Have you heard of that before? Never, no.
The average good sleeper falls asleep within a quarter of an hour.
If you don't fall asleep during the night
within that quarter of an hour period, you say to yourself,
"Valerie, I'm just going to get up,
"go do something else for a while, and I'll go back to bed
"when I feel sleepy again."
But then what if I wake up ten times?
It defeats the purpose, right?
We're trying to break a habit, a connection.
So even in the one night, you might have to do this several times. OK.
I'll give it a go. Give it a go. Yeah.
That's all I'm asking.
If the quarter-of-an-hour rule works,
it will hopefully train Valerie to get back to sleep
much more easily,
which should help clear her brain fog and improve her memory.
It's the first night, and I'm going to give this a go.
So...
..fingers crossed it all goes all right,
and that I have a great night's sleep.
Thanks to new technology, we can explore the sleeping brain
in new ways.
And a lab at Boston University recently uncovered something
very surprising about what goes on during deep sleep.
Hi, Laura. Very good to see you.
Great to get a chance to talk with you virtually.
Neuroscientist Professor Laura Lewis and her team
have made a fascinating discovery.
Using specially adapted MRI scanning technology,
they've been able to capture the first ever moving images
of the sleeping brain in action.
Sleep is something that really the whole brain does,
it's not just one part of the brain.
And so MRI gives us this really nice full picture
of how all of these different things
might be connected to each other.
Volunteers are monitored as they fall asleep
inside the MRI scanner.
If you're comfortable and ready to proceed,
can you squeeze the squeeze ball?
BEEPING
The descent into sleep is usually a very gradual process,
and we'll monitor their electrical activity of the brain,
and from that we can see what type of stage of sleep somebody's in.
Now, your brain is bathed in a fluid called cerebrospinal fluid.
Laura and her team have been studying the movement
of this fluid during sleep.
What we'd been imaging was the flow of cerebrospinal fluid,
and that's a liquid that envelops the brain, it cushions it,
but it also helps carry waste products
out of the brain eventually.
So waste products being produced in the tissue can get kind of moved
into this liquid and eventually become sort of flushed and cleared
from the brain.
And what sort of things are being washed away?
Things like amyloid.
So amyloid is a protein that's implicated in Alzheimer's disease.
So if somebody doesn't sleep, you don't get this waste clearance.
When you're asleep, amyloid is removed from the brain
at very high rates.
They spotted something remarkable -
that the waves of cerebrospinal fluid
appear in step with the slow electrical waves
generated during sleep.
This helps explain why sleep plays such an important role in helping
to flush toxins from the brain,
like those associated with Alzheimer's.
It's also really quite hypnotic.
You can actually probe into the sleeping brain in a way
that just wasn't possible a decade ago.
This is, I think, the power of MRI.
It's really incredible that we have this fully noninvasive tool
to look at just brain physiology.
I thought I knew a lot about sleep, and I have seen nothing like that.
Fantastic.
The benefits of slow-wave sleep are so profound that scientists
are now looking at how to enhance them to boost our memories
and stave off age-related brain degeneration.
Right. I've got a wonderful, exciting package here
which I've been looking forward to
because it's...
Yeah, great. It contains
these sort of extraordinary devices.
So let's see how that one goes on.
I think that goes on to my forehead there.
Right, so there are some electrodes in this band here,
which is pressed up against my scalp.
And apparently what they can do is read when you're in deep sleep,
and then what happens is when you are in deep sleep,
the machine makes some sort of noise, which apparently improves
the quality of your deep sleep.
This intriguing technology is being explored at Cardiff University's
Brain Research Imaging Centre.
One of the team researching how our
slow waves can be boosted while we sleep is Holly Kings.
When you're in your deepest stage of sleep,
which is called slow-wave sleep,
this headband can detect that, and it detects big, slow
waves of activity.
And what we do is we play the sound near the peak of one of these waves,
and we get a bigger wave, and we get more waves.
Holly and the team are hoping that this kind of sleep engineering
will help enhance deep sleep and, in doing so, improve memory.
What we're thinking is that these waves are very important
in how our memories are consolidated at night.
So that's how they go from where we initially put them,
in a short-term store,
into a long-term storage, so that we can retrieve them days,
weeks, months later.
So this is basically engineering sleep.
Sleep engineering is really about finding these different ways
to influence the sleep.
So by using sound, we can improve the efficiency
of this stage of sleep.
This shows a typical EEG reading during slow-wave sleep.
As the sound stimulus is applied, we can see the waves becoming
noticeably more powerful.
Leading the research which they hope will one day delay
the effects of cognitive decline,
is Professor Penny Lewis.
We have tried to look at how well this stimulation impacts
on the brain in younger and older people -
so is there a difference at all?
And the reason we did that is because we were hoping
that this might be a way to boost slow waves in older people
and potentially help with slowing down degeneration.
What we found is that in younger people,
you see this nice big boost in the oscillation
after the stimulation.
Whereas, in the older group - which, yes, in the ages 56 -
there is a response... Yeah.
..but it's tiny.
Unfortunately, as we age,
our slow waves aren't quite as effective as they used to be.
This means that the target the sound waves are trying to hit
is much smaller, and easily missed.
We're working on ways to optimise it, and hopefully once
it's more optimised, then it will be more effective
in an older age group as well,
and also just in a wider range of people.
Sadly, this developing technology won't be improving my sleep
any time soon.
For now, I'll keep trying as many popular tricks as I can for getting
a good night's sleep and keeping my body clock in rhythm.
I do all the regular stuff...
..making sure your room is dark,
cool and quiet.
I make sure I go to bed at the same time every night,
and I get up at around 7:15. I never have a lie in.
I go out and expose myself to the bright, early morning light,
because I know that's a good way of resetting the clock.
First thing in the morning, I do my press ups and my squats.
I could go on and on.
And here's another tech-free sleep hack
that anyone, of any age, can try.
You just need to learn how to nap like an Olympic athlete.
For top competitors, it's really important that they get
a good night's sleep.
Dr Luke Gupta is the sleep expert at the English Institute of Sport.
Napping is something in sport which has gained a lot of attention,
and if you don't do it, you're not maximising your performance.
Luke has advised rower and Olympic medallist Victoria Thornley
on her napping technique,
to make up for her early starts on the river.
When we're getting up at 6.30, we can only get in so much sleep
at night, so napping is just really important to get that extra hour
in the day, if I possibly can, of sleep and recovery time.
On training days, Victoria has a short nap after lunch.
Similar schedules are in place for all of the team's athletes,
based on two key principles.
The first one is the length of the nap, and we want
this to be kept short, so around 30 minutes is considered optimal.
The next one is to keep it early.
By early, I mean between the hours
of one in the afternoon and four in the afternoon.
It's where sleep is most likely in the daytime because you get
this little dip in body temperature that drives feelings of sleepiness.
By capitalising on the body's natural rhythms, Luke believes
it is possible to train even the most reluctant nappers.
My wife loves a nap.
I personally find it makes me feel terrible,
that I get this really sort of hungover feeling when I wake up.
Yes, I think it's just putting it into your routine.
I always call it a power nap.
You know, you don't want to do it for too long.
OK, well, I'm hoping to learn how to do it properly.
Yes. Because I've yet to achieve a decent nap.
This could be my first.
Victoria and I have each been given a quiet, dark room,
and 20 minutes on the clock for a nap.
The question is, will I be able to compete with Victoria's ability
to nap on demand?
It's the gold standard of measuring something,
what we call sleep propensity -
someone's ability to fall asleep.
Victoria's training seems to pay off straight away.
WHISPERING: So you can see here that Vicky is clearly just...
..hasn't really given much thought to this process,
and just climbed into bed and tried to fall asleep almost instantly.
And she hasn't really moved since.
Whereas I'm struggling.
The urge to sleep grows throughout the day,
thanks partly to the build-up of a chemical in the brain called
adenosine, which makes us increasingly drowsy.
So trying to go to sleep halfway through the day
can be tricky, unless you're in the habit.
KNOCK ON DOOR Time's up, Michael. Hello.
Ah, right!
So how'd you guys get on?
I think, by the end, I was probably asleep.
That surprised me, cos I would've not predicted
that I would have fallen asleep.
Even just 20 minutes of doing that feels, like, refreshing.
Research shows that a daytime nap can lift our mood
and improve our concentration and creativity.
But you may have to practise.
So do you think there are benefits,
if I continue to practise napping,
if you're not an athlete, if you're someone like me?
Yes, this is a learned behaviour that, over time, becomes habituated
and almost automated.
So the more we sort of persevere with the idea of the falling asleep
more frequently, actually builds confidence in sleep.
I liked what Luke was saying.
The idea that if you nap during the day, when you actually find
it quite difficult to go to sleep, this will give you more confidence,
you'll get more practised at falling asleep.
Luke has given me a tip that I've never tried before,
and I need all the help I can get,
as I just don't sleep like I used to.
In my youth, when I was in my 20s, I could sleep anywhere,
any place. I remember I slept in a graveyard once,
I slept in a telephone kiosk.
Then, when I hit my mid-to-late 30s,
we had young kids, disrupted nights.
Then hit the 40s,
work got more stressful,
and suddenly I'm waking up
in the middle of the night, 3am, worrying about stuff.
The link between how long you sleep and your age
was also reflected in our census.
And there were some other intriguing insights.
Women reported lower sleep satisfaction than men.
And, in general, people in the north were sleeping less
than those in the south,
and they also reported worse sleep quality.
While the shortest sleepers were in Kilmarnock.
But participants in Guernsey had the top score for sleep quality.
And we also found that almost 20% of all participants
said they turned to alcohol to help them drop off.
Which can, in fact, make our sleep more disturbed.
It's clear that the causes and the impact of poor sleep
are varied and complex.
So how much can tips and techniques really help those who've struggled
with their sleep for years?
Sian has been following her new sleep extension plan for a month.
She's settled into a healthier routine.
She's decluttering her bedroom
and has also stopped using screens late at night.
Before you received any advice, your average sleep was
five hours, 24 minutes a night,
which is below the recommendations.
And then after the intervention, after four weeks,
it went up to seven hours, ten minutes per night.
That's much better. You're looking very perky.
Yeah, good. Yes, I am. I am.
I'm, you know, a lot less tired,
and, you know, this morning I've been up since half six,
and I'm still very awake and very alert.
So a big difference, really.
Sian has increased her sleep by an incredible
one and three quarter hours.
She's now well within the recommended guidelines.
It's been a big step in her goal to change her overall lifestyle.
It has, you know, given me the confidence to actually
look at this a bit more in detail,
and actually look at my nutrition as well,
and I have started to be more mindful about what I'm eating.
Kevin has spent four weeks on the airway pressure machine
to tackle his sleep apnoea.
Hi, Kevin.
How are you getting on?
Well, I'm sleeping all right.
He's definitely better with the snoring.
As we said, your original diagnosis was a pause in your breathing
on average 51 times an hour.
He didn't believe that he was that bad, and we knew he was.
Yeah. And with the use of the machine,
that's dropped down to six times an hour,
which is a phenomenal improvement. That's phenomenal.
Within normal limits.
So, amazing. I'm really pleased at that.
Thank you. Very pleased.
Yeah.
Valerie has been following the quarter-of-an-hour rule,
and has had a slumber breakthrough.
I slept for ten hours - ten hours!
Seriously, that never happens.
I was in bed at, like, ten.
I must have been asleep by about quarter past - I didn't even read.
And then I finally woke up at about 8:25,
which was five minutes before I set the alarm, because
I set the alarm for half eight this morning,
and I was just like, "I can't believe it."
SHE LAUGHS
Inside three months, Valerie managed to improve her sleep census score
from 2.5 - clear insomnia -
to an 8.9 - insomnia free.
As for me, well, I'm not exactly cured,
but by incorporating some of what I've learned
during the course of making this programme,
I AM sleeping better.
You may feel you have already tried everything,
but I would thoroughly recommend giving a go to some of the things
that we have suggested - become your own self-experiment.
And the really good news is that sleep science is continuing
to evolve at a rapid pace, with exciting and revolutionary
solutions on the horizon.
So, time for bed, and a chance to get in as many of those wonderful
deep sleep brainwaves as possible.