Thread by @DrMikeFarquhar

It’s #WorldSleepDay

Sleep is absolutely essential to your physical and mental health

Sleep’s rhythms underpin everything you do, ensuring your brain and body are working at their best: an MoT every night!

We’re often bad at recognising that, and prioritising sleep in our lives

If you’ve had the right amount of good quality sleep, you should be waking physically and mentally ready to tackle the day ahead

#WorldSleepDay

... many of us don’t feel that way though, especially on a weekday!

Most adults in the UK get about an hour’s less sleep than they need each night ... the equivalent of missing an entire night of sleep every week!

rsph.org.uk/about-us/news/…

#WorldSleepDay

We shrug it off, tell ourselves we feel fine.

Many of us start our days with a caffeine kick to counter lack of sleep

When we prioritise sleep though, we feel better, we work better ... we make ourselves healthier

Over the course of #WorldSleepDay I’ll hopefully persuade you!

“Sleep that knits up the ravell’d sleave of care ... balm of hurt minds”

We’ve long understood sleep’s importance ... Shakespeare’s Macbeth is basically a play-length argument that we need sleep, and things rapidly go off the rails for the Macbeths without it

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Every now and then, as this @bmj_latest editorial demonstrates, the idea of widespread sleeplessness, tied into the pressures of our packed modern lives, comes into focus ... we’re just too *busy* and stressed to sleep properly!

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... the problem though is that @bmj_latest editorial isn’t from 2019 ... it’s from 1895!

“Modern life” has felt pressured for a long time now, and its effect on sleep well-recognised - you don’t get a good night’s sleep if you’re anxious or stressed

#WorldSleepDay

We tend to assume that “modern” life brings with it new problems that our 19th century ancestors didn’t have to worry about.

While that’s partly true (Brexit, Trump...), some things *don’t* change

This is my commute if I get the timing wrong ...

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Dial back to 1895 or so, and these people felt just as modern, stressed ... and sleep-deprived ... as most of us do

Some things *don’t* change that much!

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(We also get told a lot that we’re so much more anti-social these days, no-one speaks to anyone else on public transport, we’re all obsessed with our phones ...)

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... but when we dial the clock back, the technology may change, but the people are remarkably similar in many ways!

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We’ve got new 21st Century ways to combat sleep though.

In the 19th Century it might have been Dickens’ latest page-turner stealing your sleep time ... in 2019, @netflix consider sleep their biggest competitor!

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The CEO of @netflix is very clear ... he is competing with your sleep for time.

He needs you to sacrifice sleep so his company can make money (a LOT of money!)

Problem is that leaves you sleep-deprived!

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The research that’s been done so far on @netflix style binge-watching bears out how much of a negative impact it can have on your sleep quality:

psychologytoday.com/gb/blog/sleep-…

We’ll come back to *why* screens are bad for sleep later

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So ... why is sleep so important?

What is it about sleep that makes it so essential?

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One of the exciting things about being a sleep physician is that we still don’t know all the answers ... we’re constantly learning new things about sleep’s role in our lives

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What we ALL know though is how we feel when we’re sleep deprived - as well as affecting our physical health, it affects our emotional stability.

I’ll let Reed remind you:

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“For all beings endowed with the crowning mercy of consciousness, sleep is a pleasure! ... the living organism which cannot sleep, cannot live!”

(I love old-school textbook writing style!)

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At its most basic, sleep recharges our batteries and gives us energy for the next day.

It’s when our bodies repair ... and, for kids, grow!

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Increasingly, we know that sleep deprivation significantly increases risk of physical health problems, including obesity, type 2 diabetes and heart disease

It affects how we think, how we feel, and likely also increases risk of conditions like Alzheimer’s Disease

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Your immune system depends on getting the right amount of sleep!

Every winter, we put a huge amount of effort into making sure @nhs staff have had flu vaccine to protect our patients ...

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... but if you are sleep-deprived when you get the flu jag, your body takes longer to build up flu antibodies - at D10, those who were sleep-deprived will have 50% the antibody titres of someone who was well slept when they got the jag

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If you’re sleep-deprived and you’re exposed to a virus like the common cold, you are probably up to 3 times more likely to become symptomatic than if you’ve had the right amount of quality sleep

ncbi.nlm.nih.gov/pmc/articles/P…

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One of the newer-discovered functions of sleep is a nightly cleaning system for your brain: as you sleep, channels called glymphatics widen, and allow accumulated toxins to be flushed out

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... when that process can’t happen, toxins can quickly accumulate.

Over a lifetime, that is likely, for example, to be one of the factors that means sleep deprivation is a risk factor for diseases like Alzheimer’s

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Sleep also has an essential role to play in how our brains and minds function day by day.

We’ll come back later to sleep’s role in learning and emotional regulation but, when you’re sleep-deprived, your brain just isn’t at its sharpest!

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On that note, maybe time to take a break for a morning cup of coffee?

(More on caffeine and sleep later too!)

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Here’s an article I wrote for @MetroUK for #WorldSleepDay a couple of years ago to read while you caffeinate 😉

metro.co.uk/2017/03/16/wha…

Throughout #WorldSleepDay, key @nhs organisations will be talking about importance of thinking about sleep and fatigue in context of care our teams deliver

It’s essential we look after our staff to be able to deliver safe, efficient, effective care to our patients

#FightFatigue

A year ago today, recommendations for @nhs hospitals and departments about how best to #FightFatigue from @TheBMA were launched

bma.org.uk/connecting-doc…

There’s been a great response!

#WorldSleepDay

It’s also the first anniversary of the @AAGBI #FightFatigue campaign, and they also have brilliant resources to help @nhs organisations tackle this issue

aagbi.org/professionals/…

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You can read my editorial in support of @AAGBI and @RCoANews #FightFatigue work here, in @Anaes_Journal

onlinelibrary.wiley.com/doi/full/10.11…

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And a 15 minute video on why it’s so important for @nhs to think about how best to #FightFatigue for @RCoANews is here:

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At @gsttnhs, the importance of looking after our staff to make sure we deliver care to the highest possible standards is reflected in our “HALT: Take A Break” campaign:

guysandstthomas.nhs.uk/news-and-event…

(launched on #WorldSleepDay in 2017!)

#FightFatigue #GiveUsABreak

HALT emphasises the importance of getting good quality sleep for *everyone*

#FightFatigue #WorldSleepDay #GiveUsABreak

HALT makes it clear that rest and breaks are essential for staff to be able to deliver care to the standards @GSTTnhs aspires to

#FightFatigue #WorldSleepDay #GiveUsABreak

HALT also talks in particular about how to cope better with working at night ... when your brain’s natural rhythms mean you expect to be asleep, not delivering care in acute, pressured clinical areas!

#FightFatigue #WorldSleepDay #GiveUsABreak

Earlier this year, @bmj_latest launched #GiveUsABreak campaign, echoing our @GSTTnhs HALT campaign

You can hear @docanthea and I talking about issues around @nhs rest, breaks and the impact of fatigue on staff and patients in this @bmj_latest webcast

facebook.com/bmjdotcom/post…

And @nhsemployers piece here on power naps here:

nhsemployers.org/blog/2018/10/t…

Power naps on night shift can be an essential #Recharge tool to #FightFatigue and keep staff and patients more safe

@bmj_latest

#WorldSleepDay #GiveUsABreak

More detailed advice for @nhs workers about sleep and shiftwork is available from @ArchivesEandP here:

ep.bmj.com/content/102/3/…

#FightFatigue #WorldSleepDay #GiveUsABreak

It’s not just @nhs workers where we need to think about the impact of working at night - your life depends on lots of people working through the night for your safety and convenience.

How often do you think of them?

#WorldSleepDay @bmj_latest

blogs.bmj.com/bmj/2017/10/06…

Sound sleep, balanced diet and regular exercise are three simple pillars for good health for everyone

So - how do you get a good night’s sleep?

Let’s do some basics

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In turn, good quality sleep has 3 key elements:

Duration: right amount for you
Continuity: no disruption
Depth: good quality

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Getting enough sleep is often the biggest challenge ... most UK adults probably get at least an hour’s less sleep most nights than they know they need

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Everyone’s “magic bullet” amount of sleep is different, and individual to you. Most adults need somewhere between 7-9 hours sleep most nights.

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If you *need* 7 hours of sleep, and you get 7 hours, you’ll likely feel fine.

If you get 7 hours and you *need* 9 hours though ... you’ll be 2 hours sleep deprived *every* night.

Understanding your own sleep need is essential!

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A simple check is whether you sleep much later at the weekend when you can wake without an alarm.

If you do, this catch-up sleep is called social jet-lag ... and is a strong marker of sleep deprivation!

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If that’s you ... it’s worth being honest with yourself about how much sleep you REALLY need every night, and making sure you schedule enough sleep opportunity time to allow it

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There’s no universal magic solution to getting good quality sleep ... as with most things, it’s about committing to doing simple things well.

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The foundation of quality sleep is a commitment to a good core sleep routine, adopting positive sleep habits and cutting down on habits that are likely to make sleep worse

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Your bedroom should be adapted for good quality sleep ... and, pretty much, ONLY for sleeping in!

Bedrooms should be cool, dark, quiet and comfortable. It’s worth investing to get it right!

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Sex, by the way, is a happy combination of a non-sleep use of your bed and exercise that is good for most people’s sleep ... as long as *everyone* involved is satisfied at the end 😁

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A regular routine is important for sleep. Most nights, you should aim to go to sleep at roughly the same time, and wake at the same time each day ... and you need to schedule the *right* amount of sleep time for you!

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Get as much natural, bright daylight light exposure as you can ... it helps keep your body clock properly tuned up.

We’ll come back to light and the body clock later!

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Get plenty of daytime exercise ... it helps most people sleep better.

Be careful though ... for some people doing exercise too close to bedtime can make it more difficult to get to sleep (some people like a late-night gym session though!)

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Be aware of how alcohol affects sleep ... a glass of wine or beer with a meal can help people relax and wind down in the evening ... but too much can negatively affect sleep #WorldSleepDay

And be careful about how you use stimulants like caffeine ...

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Caffeine temporarily blocks the effect of adenosine, one of the substances which contributes to making you feel sleepy - so it can give a boost of alertness. But it wears off...

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Although the alertfulness wears off, the side effects of caffeine - including making your sleep quality worse! - take much longer to wear off

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The caffeine curve demonstrates some of the pros and cons of caffeine use to manage fatigue ...

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There’s also probably more caffeine lurking around than you realise ... did you know green tea can have just as much caffeine?

Or that ‘decaffeinated’ drinks still have caffeine in them?

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Some people are more genetically susceptible to caffeine’s effects than others ... but overall caffeine can have a major effect on your sleep

(Espressos in the dark not a solution!)

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Genetically, I’m a fast metaboliser of caffeine but, even so, I try not to drink caffeine after mid-afternoon as I know it can affect my sleep quality that night

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Having strategies to help you relax and wind-down are a key part of getting a good night’s sleep - different things work for different people. Working yours out can really help your sleep

The @Headspace app works for many: headspace.com

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And for more specific support around improving your sleep routine and habits, Sleepio offers a cognitive-based therapy approach that can really work for some.

@GSTTnhs our staff have free access to Sleepio as part of supporting wellbeing

sleepio.com/work/nhs/

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Let’s do some basic sleep physiology.

This is the hypnogram ... the diagrammatic representation of normal sleep. Understanding it is the key to unlocking many of sleep’s features (and mysteries!)

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We cycle through different stages of sleep through the night:

Transitional/Light: nREM 1 and 2
Deep: nREM 3
“Dream”: Rapid Eye Movement (REM)

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Healthy sleep splits roughly like this across the night:

50% in light sleep
25% in deep sleep
25% in REM (dream) sleep

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Much to parents’ frequent chagrin, we all get most of the deepest sleep we will get towards the beginning of the sleep period.

After that sleep is more light sleep and REM

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Sleep stages have different functions

Deep sleep broadly supports physical growth/repair

Light/REM sleep broadly important for learning, emotional regulation, memory processing

But sleep’s complex, we still don’t understand it all and this is a simplification!

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The rhythms of wake and sleep are reflected in almost any physiological system you choose.

Our brains and bodies depend on those rhythms to function properly

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Growth hormone secretion, for example, is tied to sleep, with the biggest pulse coming during deep sleep.

If sleep is disrupted, children can ‘fail to thrive’ ... not grow as well as they should

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Sleep quality can be affected by lots of things ... and when that happens the hypnogram, the representation of the architecture of sleep itself, becomes fragmented.

That has consequences!

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Someone whose hypnogram looks like this may *think* they’ve been sound asleep but, because the quality is poor, they will still feel the effects of being sleep deprived the next day

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In children, many common conditions can contribute to sleep disruption.

Improving sleep quality can involve a bit of detective work!

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For children and adults alike, stress, worry and anxiety can be a really potent cause of sleep problems.

Improving sleep often needs the source to be identified and treated - which can be v challenging with anxiety!

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(Every now and then I get to prescribe “Monster Spray” in my clinic, and it’s really satisfying when it works 😁)

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(By the way, when I’m explaining the hypnogram in clinic to children and families, it tends to be a bit more dynamic and uses a LOT of Sharpies 😁)

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“Healthy sleep is a rhythmic act, and rhythmic sleep must be cultivated”

The most fundamental rhythm of sleep is our body clock, our circadian drive, which acts like a master control to keep us awake by day, asleep by night ... unless we choose to fight it!

#WorldSleepDay

Our circadian rhythm (Process C) is one of two major processes that regulate our sleep and wake.

The other - Process S - is our sleep drive.
The longer we are awake, the more tired we feel

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The interactions between sleep and alert drivers are a bit more complex than that ... and that means most people feel a bit more naturally sleepy in the early afternoon

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... the post-lunch dip is driven by your body clock physiology.

Some cultures encourage a siesta ... in the UK we’re perhaps more likely to go and get a double espresso!

(We also see this post-lunch lull reflected in accident incidence figures)

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When we go against our body clocks - for example if we travel long-distance and are jet-lagged - we feel the effects of our brains and bodies being out of sync with the world

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Everyone’s body clocks are wired slightly differently ... many people will know if they are a morning “lark” or an evening “owl”

This body clock preference is partly genetic

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Most people’s body clocks don’t run to a 24 hour day:

~75% have body clocks >24hrs
~25% <24hrs

We constantly resynchronise our clocks every day.

Light is crucial to that process.

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The 2017 Nobel Prize in Medicine was awarded for work better describing how our body clocks work.

It’s going to be a major area of development in 21st Century healthcare, as we tailor people’s medical care better to their own unique biological rhythm

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Let there be light!

Light is the most powerful external influence on our body clocks.

Regular exposure to light and dark entrains our sleep cycle.

We use “zeitgeber” - ‘time giver’ - to describe any factor which can do this

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When you travel far enough around the world to be jet lagged, the pattern of exposure to light and dark in your new time zone is what readjusts your body clock to synchronise with local time

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Historically, the only available light sources were sun, moon and fire ... our body clocks evolved to match that:

Day = bright light = wake
Night = dark/dim light = sleep

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That changed, dramatically, with the advent of electric light.

Suddenly ANY time of day could be brightly lit

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This is the difference in light exposure between people living in a traditional hunter/gatherer society and a modern industrial society

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Light has a major effect on your body clock.

When your brain is exposed to bright light when it doesn’t expect to be, it is the same as telling your body clock you’ve moved time zones

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If you, in the UK, kept yourself awake with bright lights until 2-3am for several nights in a row, this is the equivalent of telling your body clock you are now in New York.

When you then try to go to sleep at 10pm ... your brain thinks it’s 5pm - so, no sleep!

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This is what you are doing to your brain and body clock when you do this ...

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Light in the evening also suppresses melatonin, the signal the brain sends to your body to encourage sleep

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And the brighter the device, the stronger the effect

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The screen device companies will try to persuade you that night modes are the answer ... but the evidence coming in suggests they don’t significantly reduce the impact of electronic light on sleep.

journals.sagepub.com/doi/abs/10.117…

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There is also a psychological effect ... the Wikipedia or YouTube “black hole” that keeps you awake until the early hours ... or @netflix skilfully encouraging you to binge watch!

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For good sleep, get plenty of light in the daytime ...

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... but at night, aim to dim light as much as possible and, for best chance of a good night’s sleep, have an electronic curfew 1 hour before bedtime and ban screens from the bedroom altogether.

Family docking stations are a good way to remind everyone!

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Try not to make this how you approach electronic screen devices at bedtime!

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It leads to one of my favourite sleep “cures” though - go camping to reset your body clock!

bbc.co.uk/news/health-38…

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Sleep changes across the lifetime, in duration, timing and proportions of different sleep stages.

Babies, for example, sleep longer overall, but in shorter bursts, and spend much more time in REM-like sleep - supporting the huge brain growth in first year

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Children develop sleep patterns parents hope for at different ages, just like children will be dry by night at different times

Honest truth is children have been disrupting parents sleep since the Stone Age. Often it’s normal variation, and not a medical problem

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Remember I said everyone’s “right” amount of sleep is individual to them?

That’s true of babies and children too, and it can be quite a wide range of normal!

At 6 months, normally developing babies may sleep as much as 16.5hrs or as little as 10hrs per 24 hours

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At any age, we try to avoid absolute answers for how much sleep someone needs ... the range of normal is quite wide across the lifespan.

Only *you* can really work out how much sleep *you* need.

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This zooms in on the sleep duration ranges during childhood and teenage years - big difference if you’re a teenager who needs 11 hours of sleep every night compared to one who needs 7!

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And remember the hypnogram, and how we sleep in cycles?

At the end of each cycle it’s normal to briefly wake and settle back into sleep; as adults we don’t usually remember these brief wakings

But babies and children need to learn to settle back into sleep

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The age that children develop the ability to settle back into sleep is variable, and is influenced by a number of factors, some of which are influencable and some aren’t.

Wakings that affect parents sleep can be normal in even quite old children

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It all means that normally-developing children’s sleep patterns can have a profound secondary impact on the quality of their parents’ sleep

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When children don’t sleep, it can have a huge impact on their parents physical and mental health.

Better advice about sleep earlier can help - the answer is very rarely fancy tests, or sleeping medicines

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It can take up to 6yrs until parents’ sleep returns completely to baseline after the birth of a new baby

Advice can help, but the key is often support ... and not unnecessarily medicalising what is still usually normal development

academic.oup.com/sleep/advance-…

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Older kids can have very strong opinions of their own about whether they want to go to sleep or not ... and the day I have a guaranteed “cure” for that, I’ll be a very rich man!

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Dr Doom is right though ... children benefit even more than adults from getting the right amount of good quality sleep most nights.

That means sticking to a good general routine and sleep habits most nights

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A guide to common sleep difficulties in typically developing kids from @EvelinaLondon team can be found in @ArchivesEandP here:

ep.bmj.com/content/101/4/…

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Other good first-line resources for parents wanting to optimise their children’s sleep as early as possible:

BabySleep.com - great team of international paediatric sleep experts offering advice

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And the raisingchildren.net.au website from Melbourne Children’s Hospital is a great parenting resource covering children of all ages, over a wide range of topics, including sleep

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When all else fails, there’s something therapeutic in listening to Samuel L Jackson reading a soothing bedtime story ...

(Warning: NOT for young ears!)

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Let’s go back and talk about some more functions of sleep itself, focussing on the mental benefits of sleep

Remember that most deep sleep, which physically recharges us, is early in the night?

Light and REM sleep, which support learning and emotion, are later

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Your brain is a bit like your email - it only has so much room for new information before you need to delete unneeded stuff.

Sleep empties your cache each night - which allows you to learn new info the next day.

Poor sleep = poor ability to learn

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During sleep, your brain decides what new information needs to be kept - and transfers this to long-term memory, so you can recall it in future.

If you don’t sleep well, you won’t retain and integrate new knowledge as well - and will score worse on exams!

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If you are learning new skills, your brain will continue to rehearse -and improve them- as you sleep

That’s why you can go to bed having not quite “got” a new skill, and wake up the next day able to do it much better

Most of those functions occur in light sleep

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During dream sleep, a very different sort of thinking is taking place: your brain effectively free-associates new information and old, which can throw up new insights and ideas.

Dream sleep helps support creative thinking

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It came to me in a dream!

Kekule, puzzling out the structure of benzene, dozed off, dreamt of demon snakes eating their own tails ... and woke up realising the structure was circular (a completely new idea)

#WorldSleepDay

‘Yesterday’ came to McCartney in a dream ...

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... as did the killer opening riff of Satisfaction to Keith Richards

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Dream sleep also plays an important role in emotional processing and regulation. REM-deprived, you’re more likely to be anxious, irritable and impatient

If both partners in a relationship are REM-deprived, arguments are much more likely to be emotionally hostile

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Crucially, we get most REM and light sleep towards the end of the night, which means if we’re generally sleep deprived, these are the bits of sleep we’re likely missing: the bits that make us smarter, more creative, more stable and generally nicer to be around...

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It means good sleep is essential for learning - and nowhere is that more relevant than for children in school

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It’s one reason why @EvelinaLondon Sleep Team have worked with the @PSHEassociation to get lessons about sleep into schools

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theguardian.com/lifeandstyle/2…

You can hear @psychosomnology and I talking with the @PSHEassociation team about the new school sleep lessons, and why we think they’re so important in this podcast:

pshe-association.org.uk/news/new-pshe-…

Paediatric sleep medicine is a relatively new specialty, with not many of us doing it!

Sleep medicine is a mix of common sense general paediatrics, neurology, respiratory, mental health, neurodisability and community paediatrics.

Sleep affects everything!

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Our specialty might be fairly new, but as long as doctors have been thinking about children’s health, they’ve been thinking about their sleep!

This, by Thomas Phayre, is from the 16th Century Boke of Chyldren - first English-language paeds textbook!

#WorldSleepDay @RCPCHtweets

Sleep problems in children are common, and most can be dealt with by applying simple knowledge, experience and advice consistently.

More kids with sleep problems need super nanny rather than a sleep doctor.

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While many sleep problems either relate to issues with sleep routine or habits, or to the effect on sleep of other medical problems, there are >100 disorders of sleep itself.

Most are treatable

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Children’s sleep services like those @EvelinaLondon are here to help in assessment/management of complex, rare and refractory sleep diseases/disorders

We do as much public outreach work as we can to try to help as many people as possible

evelinalondon.nhs.uk/our-services/h…

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Because being a children’s sleep doctor is a bit, well, weird, the @PaediatricFoam team came to ask me about how I ended up doing this:

#WorldSleepDay @begley_roisin @PriyenShah86 (thanks both!)

https://twitter.com/paediatricfoam/status/974636880359804928?s=21

I’m not going to talk about all the different sleep diseases/disorders today, but I am going to mention one that is a very personal one for me: sleep paralysis

I’ve had recurrent episodes of sleep paralysis since my teens; they’re why I ended up a sleep doctor

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Sleep paralysis is the sensation of waking up but feeling as if you can’t move, often associated with a feeling of pressure or restriction around your chest.

It can also be accompanied by very vivid visual hallucinations - often interpreted as supernatural

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No matter how knowledgeable you are about it, and how familiar you are with it, sleep paralysis episodes often remain an intrinsically terrifying experience

The original meaning of night-maere relates not to a horse but to a demon ... sleep paralysis

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Many cultures, all across the world, have a myth of a demon who comes in the night and attacks people in their sleep

In medieval times, incubi and succubi were demons who would come and sexually attack men and women in their sleep

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The ephialtes was a demon from Ancient Greece who would leap upon people as they slept and cause nightmares

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The luupainaja is an Estonian demon who “stalks your bones” in your sleep

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In Japan, the kanashibari demon will make you feel as if you are bound in metal as you sleep

All across the world, and all the way back to the dawn of history, cultures report phenomenon we now recognise as sleep paralysis

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Sleep paralysis occurs as a partial transition from REM to wake. Elements of dream intrude into wake, so you always feel like you are in the place where you fell asleep.

Often accompanied by visual and other sensory sensations - hypnagogic/pompic hallucinations

#WorldSleepDay

During REM - dream sleep - tone in your voluntary muscles drops to virtually zero. This means you are paralysed. Sounds scary, but it’s essential to stop you acting out your dreams in your sleep

Normally we’re unaware of this paralysis as it stops as we wake

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In sleep paralysis this persists

You try to take a deep breath in, but can’t because accessory muscles of respiration are paralysed

Your brain interprets that as pressure on your chest, or a band around it, or choking sensation

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There is almost always a sense of primal fear and terror, and a sense of a threatening presence, either seen or just out of the eyeline.

It’s terrifying as an adult with a detailed understanding of sleep.

Imagine it happening to a 5 year old.

#WorldSleepDay

In modern times, I think sleep paralysis and hypnagogic/pompic hallucinations account for many reports of alien abductions and nocturnal supernatural encounters

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The best (only!) teaching I had about sleep medicine at medical school was doing parapsychology @EdinburghUni during my psychology degree, scientifically explaining the paranormal

(From the excellent Prof Bob Morris, first Professor of Parapsychology @EdinburghUni)

@KPUNews

There is genetic element to susceptibility; can occasionally track through families.

As with most sleep problems, SP much more likely to occur if you’re not getting enough good quality sleep: focus on improving core sleep routine and habits, cut out usual culprits like caffeine

Sleep paralysis is found much more commonly in people who have narcolepsy, as are hypnagogic hallucinations BUT most people who have episodes of sleep paralysis don’t have narcolepsy.

#WorldSleepDay

If you do get sleep paralysis:

- try to stay calm (not easy), focus on slow calm breaths
- focus on ONE part of your body and move that. Once you get ANY movement, paralysis usually breaks. (I usually wiggle my toe)
- external sensory input (eg touch) can help but tricky to do!

Sleep paralysis still makes me feel scared when it happens but it absolutely fascinates me at same time; a glimpse into the amazing physiology of our sleeping brains and bodies

It’s also a great example of how sleep is all about science, stories and social lenses

#WorldSleepDay

We all spend about a third of our lives asleep.

Every human who’s ever lived, has shared this brilliantly bizarre thing that we all do and all take for granted - and we’re only now beginning to really understand.

#WorldSleepDay

Sleep has an innate biological rhythm, but it can also be modified by social and cultural influences - siestas are normal in some places, frowned on in others for example.

#WorldSleepDay

Sleep slips into our language and our ideas and as we sleep, we dream of the impossible ... and sometimes when we wake up we do it.

For me, where science meets story, our sleep is all about what makes us human.

That fusion of culture, biology and human imagination is amazing

It’s why I love @neilhimself’s Sandman so much ... it was practically written for me (a geeky comics-loving sleep physician-to-be, already fascinated by sleep because of the weirdness of sleep paralysis)

Every time I come back it it, I take something new away

(My Sandman volumes live by my bed ... with some duplicates in my office in work 😁)

I’ve almost run out of #WorldSleepDay, so much about sleep I haven’t even touched on

Hopefully I’ve not filled up your timeline too much, and you’ve learnt something new or interesting or useful about sleep.

(This was me as a kid...I didn’t need an iPhone to stop me sleeping!)

Sleep helps define who we are.

Sleep is still full of mystery and magic and wonder.

It’s where science meets story, where medicine meets myth.

It is both rhythmical and random, and it’s a privilege to spend so much of my life delving into it.

#WorldSleepDay

Thank you, as always, for reading and responding (and indulging!) - I hope it’s given a bit of an insight into why I think sleep is so fascinating.

And, sleep well!

Tomorrow is another day.

#WorldSleepDay

If you want to carry on delving into the world of sleep, I thoroughly recommend these books:

@neilhimself: The Sandman
@sleepdiplomat: Why We Sleep
@guylesch: The Nocturnal Brain

#WorldSleepDay