It’s not only Dr Who that benefits from regular regeneration. Every night you regenerate too.
Your cells are repaired, your muscles refreshed, your brain sweeps clean the dust and detritus of the day, tries to make sense of it all and files away what it thinks important.
Sleep is crucial for a healthy and productive life. Yet many thousands of Kiwis struggle to get useful sleep, whether at night or by day. Some can’t fall asleep, others cannot help doing so. Some sleepwalk, others grind their teeth.
More than 80 sleep conditions have been characterised in the International Classification of Sleep Disorders, published by the American Academy of Sleep Medicine. This recognises six types, each with its own sub-categories — insomnias, sleep-related breathing disorders, hypersomnolence, circadian rhythm sleep-wake disorders, parasomnias and sleep-related movement disorders.
Between them, they cover sleep apnoeas, narcolepsy and cataplexy, jet lag, night terrors, sleep paralysis and restless legs syndrome.
Just reading the list is enough to make you lose sleep.
Those suffering from a lack of sleep can be referred by their doctor to specialist hospital sleep physicians, though the wait may be from six months to almost two years, depending on where you live.
A sleep physician will provide medical treatment to help cure the underlying issues, which may include equipment to relieve sleep apnoea or medication.
Or you can go to accredited sleep coaches, who train the sleep-deprived to adopt healthier slumber habits by changing their lifestyles and sleep environments.
If you’re one of the lucky ones who sleep soundly, enjoy a vivid dream world and then wake up reinvigorated the next morning, it’s time to spare a thought for the many who dread bedtime and a very long night with either little or highly disturbed sleep.
You’re chatting away with old workmates, but the conversation seems a bit random and jokes that seemed hilarious aren’t really that funny. Everything’s strange — the people you thought you worked with at one place are now working at another, wearing weird clothes and the streets outside are not how you remember them, with odd-looking cars driving randomly. Then it starts snowing. And you’re darn sure the person you’re talking to died last year. When they bring out their pet Tyrannosaurus rex and ask if you want to pat it, your rational brain is starting to struggle, the credibility bubble bursts and you suddenly wake up.
For many of us, dreaming comes towards the end of the model sleep cycle, which lasts between 90 and 120 minutes. We’ve gone through the light, hazy, short first stage of sleep, during which we can be woken easily, into stage two, when we relax more deeply. This second stage can last between 10 minutes and an hour. Our temperature drops and the heart and breathing rates slow.
After that, we have a 20 to 40-minute period of deep/slow-wave sleep, during which the body repairs cells and tissue and builds bone and muscle. Finally, there is the dream or REM (rapid-eye movement) sleep stage. This final stage typically lasts about 10 minutes in early cycles, and up to an hour in later ones.
In an undisturbed night, you can have four to six such cycles. But caffeine, alcohol, nicotine, irregular bedtimes, dozing too long in the afternoon, blue-light exposure, stress, certain medications and sleep disorders can cause havoc.
Dunedin sleep consultant and coach Dr Liesel Mitchell uncontrollably falls asleep three or four times a day, even with medication and management.
Mitchell, who runs The Sleep Lab with Gary Peters, has narcolepsy, a condition that takes you straight to the REM stage of sleep, caused primarily by a loss of brain cells that produce hypocretin, a neurotransmitter which regulates being awake.
Worldwide, about one in 2000 people have narcolepsy, and about 200 of them live in Otago and Southland.
‘‘You are always just on that edge between sleeping and waking,’’ she says. ‘‘It is very confusing. And you can fall asleep in the middle of a conversation and start talking about the dream that you are having.’’
‘‘As I start to talk about the dream, as it comes out of my mouth, I realise that’s not the right thing to be saying. So, if I started saying in this conversation, ‘oh they’re just sitting over the hill’. You’re like, ‘what?’. And I’m like, ‘no, no, that didn’t make any sense, did it?’. So, I’ll start to realise as I speak.
‘‘I’ve come to realise that my memory is probably not as reliable as I would like to think. There’s lots of things that I can’t be sure of. I remember thinking, ‘did I go and see Flight of the Conchords?’. I used to love them and I had this dream that I’d gone to see them. And then I saw on Facebook, a memory popped up and it said, ‘at Flight of the Conchords, so amazing, can’t believe I’m here’ and I was like, ‘oh, it wasn’t a dream’.’’
Mitchell also has cataplexy, in which the muscles become paralysed due to strong emotions, such as laughing, surprise or anger.
‘‘I was 14, on a music camp with some friends, and standing on a bleacher with another
friend who’d just make me laugh all the time, and I fell off the bleacher and hit the floor. And I was like, ‘that’s very strange’.
‘‘When I got home from school camp, I told my mum about it, and she was like, ‘that’s just you being a big drama queen’. Then I was with another friend and my mum, and we’re walking through the New World carpark in Dunedin. My friend and I were talking and she made me laugh, and I fell over on the concrete in the middle of the carpark in front of my mum. And she was like, ‘oh, that’s odd’.’’
Mitchell’s doctor suggested she see a specialist, thinking it could be heart related.
‘‘They discovered it could be this thing called cataplexy, ‘so we’ll send you to neurology’. And it got a bit scary.
‘‘They tested me for sleep, did a whole lot of EEGs and a sleep latency test to see how quickly I went to sleep. And they said it is this thing called cataplexy and I would develop symptoms of narcolepsy. Both of those words meant almost nothing to me, and they handed me some medical journals and said go away and read.
‘‘Cataplexy is basically when strong emotions, laughter, fear, surprise, anger, things like that, release chemicals that would normally be released when you’re sleeping, to relax your body, but basically it’s all out of whack. Your muscles literally all just go weak and you’ve got no control at all. You’re fully conscious, but kind of unable to move.
‘‘You know those giraffes that are kind of those little kids’ toys, on a little platform, and you sort of push under it and they just collapse? It’s like that.’’
‘‘Somehow’’ Mitchell passed her BA in art history and theatre studies at the University of Otago.
‘‘I was falling asleep in all my lectures. My friends would see me sitting here and my pen would start drifting off the page. And then they’d see me wake up for a point that might have been really pertinent, something brilliant. I’d write it down and then go back to sleep.
‘‘I was falling asleep watching slides of Italian Renaissance art. I was asleep as soon as I turned the lights out. Why was I doing art history? What a crazy choice! Theatre studies was much better because it was much more hands-on and active.’’
In 2023, she completed her PhD at the university’s National Centre for Peace and Conflict Studies on Moving the Masses: Does Nonviolent Discipline Matter?
Mitchell carried on with her life, working as a quality manager for a small, global New Zealand company, and dealt with narcolepsy as well as she could. She trained as a patient advocate with the United States-based sleep research organisation Project Sleep.
At the end of last November she was made redundant. That was the opportunity she had been waiting for and the catalyst for The Sleep Lab.
‘‘For years I’d lived with this and thought of it as something that I live with but that wasn’t really a big part of me, it’s just this thing. But I suddenly realised it’s a huge part of my life, but I’ve also got all this knowledge about sleep and with that experience maybe I could help others.’’
Sleep has been around an awfully long time, Wellington Hospital sleep physician Dr Andy Davies says.
‘‘Ever since single-cell organisms, sleep has been a thing. Even microbes have a 24-hour cycle. We think it’s to do with recovery, to do with sorting, resetting metabolic processes, to do with healing.
‘‘Your brain cells use energy faster than they can get rid of the debris from all the metabolic processes that go to run brain cells. So, if you run a brain cell constantly, without a standby period, for want of a better term, the metabolites all build up and they become less efficient. That’s partly why we think that people who haven’t slept properly don’t think straight, because your brain cells haven’t cleared out all the waste.’’
Davies works with the University of Otago’s Wellsleep Centre in Wellington. He says even people with good sleep patterns can experience periods of sleeplessness or sleep disturbance, due to being anxious, or caused by jet lag, shift work or even daylight saving time.
‘‘Insomnia is by far the commonest. A good 60% of people will experience insomnia at some point. When these periods start affecting your daily life, your ability to work, and some people can be completely debilitated, you need to do something about it.
‘‘The next commonest thing we see is sleep apnoea, a collapse of your airway when you fall asleep. And the incidence of that has been going up as obesity rates have been going up. It’s not just obesity which causes it, but it is the biggest risk factor that is increasing.
‘‘Up to 40% of the population in some regions of New Zealand have sleep apnoea. New Zealand is particularly high because of our obesity rate.’’
While alcohol is a soporific, the quality of sleep after drinking is worse, he says.
‘‘And you don’t get deep sleep. So, for people who’ve had alcohol, same with cannabis, your brain’s much more active when you’re asleep, so you don’t get the inactive brain state, so your cells can’t clear out all the debris, and next morning you are less rested because your brain’s been busier, even though you slept more.
‘‘The other thing that affects middle-aged men with too much alcohol is the incidence of sleep apnoea is much higher in that group. Alcohol relaxes your muscles more, so the muscles at the back of your throat relax more, so your sleep apnoea is a lot worse.’’
