Getting serious on sleep

Unfortunately, everyone has probably had sleep issues at some point in their lives. For some, it’s a nuisance, for others a - in some cases literal - nightmare. But could changing the way we think about sleep actually help us to sleep better? Paul Blenkiron thinks so. He's an NHS consultant psychiatrist and a member of the Royal College of Psychiatrists, and he spoke with Katie Haylor...

Paul - When I look back at a survey that was done back in 2010, which is the Great British Sleep survey, this showed that about a third of people have chronic insomnia, they've had difficulty sleeping for at least two years. Research shows that people physically get more problems with diabetes, obesity, high blood pressure if they don't sleep as much as they would like to or want to, and also there are mental health problems linked to sleep problems such as anxiety and depression or simply just not concentrating during the daytime.

Katie - Is it possible for you to summarise what kinds of issues people can have with sleep, because it's not just not getting enough is it?

Paul - That's right. Sleep could be too much, it could be too little, or it could be broken or just dissatisfied for people. Sleep really is part of our sleep/wake cycle and that's linked to stuff in the brain that controls our daily routine. So there's a group of cells in the brain, called the hypothalamus, produces this hormone called melatonin, this is a hormone that makes you sleepy and you produce more of this melatonin when it gets dark. So, of course, when it gets to the light times of the year, such as the summer, people sleep less, in the winter they sleep a bit more.

It’s sometimes people’s perception of sleep which is the problem rather than the actual amount. And people normally wake up during the night for one or two minutes a couple of times a night - so-called micro wakes - and we're normally not aware of those. But if you're bothered by your sleep, you’re going to pay more attention to those periods of waking up and, of course, that sets off this vicious cycle of worrying about your sleep.

Katie - At what point would a psychiatrist like yourself come into contact with people who are having sleep issues, because I'm guessing this goes a little bit beyond the sort of common sleep hygiene type routine stuff that people might be more familiar with?

Paul - Relatively few people with sleep problems will come to see a psychiatrist. I would tend to see people who had problems due to a mental health problem that was linked to sleep such as depression or anxiety, or some sort of stress. But a lot of GPs will see sleep problems quite commonly either leading to mental health problems or mental health problems leading to sleep. In depression, we know that people have poor sleep; they sleep too much or too little but, of course, if you're not sleeping already you become depressed. In that survey I talked about, 80% of people had low mood due to their sleep problems, 75% had poor concentration, and half had a relationship problem, so I think it's a bit of a chicken and egg situation. It can be difficult to disentangle those, even for somebody like me who sees quite a few people with this problem.

Katie - So, from a mental health perspective, are there particular elements of sleep that you would pay particular attention to?

Paul - There's quality and there's quantity. First of all dealing with quantity, we know that as you get older you need less sleep. New-born babies perhaps 18 hours, adults like you and me probably 7 to 8 hours for a good healthy night sleep, and even less as you get older. And, of course, Margaret Thatcher famously needed only four or five hours a night of sleep. So, I tend to look at people’s expectations of sleep as much as the content.

Katie - And could you just describe for us the various stages of sleep and what the brain's doing throughout the night?

Paul - We have two main types of sleep: slow wave sleep and REM sleep or rapid eye movement sleep. The REM sleep period last about 60 to 90 minutes at a time. They get more common as the night goes on and during those periods of time you're sleeping lighter than before and more likely to dream during those periods. People, if they're woken during slow wave sleep, tend to be really irritable, disoriented and confused, and in REM sleep if they’re are woken then they'll probably remember the dreams they've been having.

Katie - Is there any connection between the quality or quantity of dreams and mental well-being?

Paul - Well, this is a fascinating area and, of course, it was Sigmund Freud more than a hundred years ago who said that "our dreams are caused by unconscious impulses, unfulfilled wishes." I think there are few mental health professionals these days that would really interpret dreams in the same way. But we do know that people are bothered by dreams sometimes. If you’ve had a traumatic experience in your life you might get flashbacks or nightmares to that trauma and it might come out in the dream. But for most clinical people, I would say they're not really so concerned about the content unless the patient in front of them is concerned about it, they're more concerned about the overall quality of sleep, and dreams can be affected by mental health problems and by certain medications.

Katie - What can be done to help people who are suffering from bad sleep? What might you be doing as a psychiatrist?

Paul - First of all, address the cause of the sleep problem. Common sense tells you that if you've got a noisy room or your partner snores then that's the issue that should be dealt with. If there's some sort of heart problem that's keeping you awake or some sort of asthma, then get that treatment. So first of all deal with the cause where possible.

The second thing to do is to look at lifestyle changes, something that's called sleep hygiene. Even before people see me, I'm sure their GP will have given advice on avoiding caffeine and alcohol, using the bedroom just for sleep and little else, and generally making sure there's a regular routine.

When they get to see me I've got 2 interventions I could offer. Medication is one possibility, but a better, more long-term solution is to consider Cognitive Behavioural Therapy.

Katie - So this is actually changing the way people are thinking about sleep or the reasons why they're not sleeping, is that right?

Paul - That's a good summary. The B part first of all is about your behaviour, so often we might get people to keep sleep diary and, for example, if they’re only getting an average of 5 and a half hours sleep, we get them to go to bed a bit later than normal, maybe 1a.m. if they need to be up for 7 a.m. The key thing here is not to sleep in in the morning and to train yourself to get up after that 6 hour window for sleep to begin the day. That's the behavioural part of things.

The C is cognitive, which is how you change your view of sleep. We all know from sleep problems that when we're lying there in the middle of the night, these unhelpful thoughts keep going round our head - “I'm never going to sleep”, “everyone else is sleeping” and “I might go crazy if I don't get enough sleep”. And the idea of CBT is to encourage people to have more helpful and realistic thinking. So I might encourage people to train themselves to say in the middle of the night; this doesn't matter, I can function well enough without sleep; I'll sleep better tomorrow; I'll fall asleep when my body is ready.

The key thing, of course, is not to actually try and get to sleep because if you try really hard to push a thought out of your mind, back it comes again. So we practice a form of psychological adjustment called mindfulness. Letting your thoughts stay with you, being okay about that and being, so to speak, chilled out in bed, ready for sleep when it takes you.

Katie - How effective can this cognitive behavioural therapy be first of all, and also does having a pre-existing mental health condition just make things all the much more complicated when it comes to CBT?

Paul - Most CBT on the NHS is offered for other mental health conditions. So the National Institute for Health and Care Excellence recommends CBT for pretty much everything in mental health as being a good treatment, but it’s also useful for sleep problems on their own. It does complicate things when there are other problems present and we will treat depression and anxiety in other different ways. But CBT is still a useful intervention and in the right hands and if people actually do it, it can help at least three out of four people.

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When it comes to memory, the importance of sleep goes well beyond the negative impact of being tired. The process of sleep plays an active role in memory formation. So says Anna Weighall - cognitive psychologist from the University of Sheffield, and she spoke to Katie Haylor. First up, Anna explained how sleep helps to integrate new information learned that day into pre-existing information stored in our brain...

Anna - We, as human beings, children or adults can learn new information really quickly and easily. So, for example, we might learn a new word - I'll introduce one now, for example, hippocampus. Hippocampus is a little part of the brain the shape of a seahorse that's really important for memory and, in particular, when we learn something new, like the new word hippocampus we’ll initially store it there, so that happens while we are awake.

Imagine we've learnt this new word and now we need to put it in our mental dictionary with all the other words that we know already. Well what seems to happen during sleep is that the new words stored in our hippocampus, which is like a temporary bit of memory if you like, transfers into our long-term memory which is stored in the neocortex. And it looks as though sleep actually facilitates it helps the links between the immediate memory in the hippocampus and our long-term memory in the neocortex.

Katie - Can we see that effect happening in the brain waves?

Anna - Yeah. So, we can see it in several different ways. Thinking about the brainwaves, in a sleep experiment a researcher might invite participants to come into the lab to learn some information and then to stay overnight or to have a nap in the lab, so your brain waves will be recorded. We can then look the next day at how well the participant remembers the information they learned previously, and we look to see whether they remember more or less than they did before they went to sleep. And we can then look for associations between the brain activity, so how much of certain types of sleep did you have, and we can look for a relationship between that and how much you remember the next day. Spindles are little sharp spikes in the electrical activity that happen during that slow wave sleep. Neuroscientists believe that those are associated with transmission of information and the connections from the hippocampus to the neocortex.

Katie - So now we know why sleep is important for memory and learning, what effect can suboptimal sleep have then on someone's ability to remember something?

Anna- Not having enough sleep, or learning information and then not sleeping on it, might cause you to forget more of that information. It will depend, of course, on what that information is. Just occasionally having a poor night's sleep, I don't think we need to worry that that's going to drastically affect our memory. However, we do know that if people are tired, in the short term it will affect their performance on a given day so it might affect their ability to encode memory because they're tired. And, over time, if people are consistently sleep deprived then again that can affect their memory abilities.

Katie - Most people are probably aware of general sleep hygiene, things that are common sense, a good idea, sometimes difficult to implement. Does it go beyond that?

Anna - Especially with children and young people, encouraging them to have good sleep habits is a really good place to start. At the University of Sheffield, the hospital, and in collaboration with an intervention designed by the Children's Sleep charity, they've shown that you can actually improve sleep by as much as 2 1/2 hours. You can increase a child's sleep by as much as 2 1/2 hours where they've been experiencing difficulties and where the family becomes involved in an intervention that improves attitudes around sleep and bedtime behaviour. That's actually a much bigger improvement than we've seen in the leading trial using melatonin, which is a hormone that’s sometimes used to improve sleep.

Katie - If sleep is so important for learning and memory, is there anything about sleep that we can tweak to help us be better at remembering things?

Anna - This is a very exciting emerging area of neuroscience, I think, and we certainly still don't have all the answers. But a few researchers in a few labs now have demonstrated that you can actually change the properties of sleep using quite simple techniques. You can boost the power of slow wave sleep, the depth of the slow-wave so you make the slow-wave sleep perhaps last for longer and perhaps have more potential to affect learning and memory. So, you kind of make that deeper sleep even deeper perhaps is a way to think about it, using something called auditory stimulation. Monitoring somebody's brainwaves while they sleep and once they begin to enter a phase of slow-wave sleep they are played a noise,  pink noise, which if you've heard of white noise, pink noise is basically very similar, it sounds similar if you've heard it, it's just not quite as crackly. And what they do is synchronise the onset of this pink noise with the onset of the slow-wave sleep and by doing so you can actually see these sleep waves changing in a measurable way.

This is a very experimental technique and it needs further replication, but there is preliminary evidence that suggests that boosting slow-wave sleep in this way can be associated with increases in memory recall for information that you learnt before that sleep, so that's been shown in studies with adults. And there’s some very preliminary emerging evidence that there is potential for this sort of intervention in atypical populations, for example children with ADHD. So there's still a lot to learn, but if that finding bares out, then that's potentially very powerful intervention that might help people who have problems sleeping.