Sleep-J.E
Sleep is an important part of your daily routine. About one third of your day is spent sleeping. It is essential. Sleep is important for how nerve cells communicate with each other, and everybody needs sleep. Sleep is complex and is a dynamic process. It is not like a light bulb which is either on or off; but has different stages.
STAGES OF SLEEP
There are 2 main types of sleep: Rapid Eye Movement (REM) and non-REM (NREM). Sleep cycles between NREM and REM sleep through the night, with increasingly longer, deeper periods of REM sleep occurring nearer the morning. It is normal to wake up several times - although we may not remember doing so.
NREM is divided into 3 stages: light sleep, deeper sleep and deepest sleep. Each of these stages are linked to specific brainwaves and activity of the nerve cells, (neurones).
STAGE 1 of NREM sleep is the changeover from wakefulness to sleep. This lasts only several minutes of relatively light sleep.
STAGE 2 of NREM sleep is a period of light sleep before entering deep sleep. The heartrate and breathing slow down and muscles further relax. The body temperature drops, and eye movements stop. Brain wave activity slows- but there are still bursts of activity albeit brief.
STAGE 3 of NREM is the stage required to feel refreshed in the morning. It occurs in longer periods in the 1st half of the night. Your heartrate and breathing are at their lowest. Your muscles are so relaxed it may be difficult to wake you. Brain waves are slower.
REM SLEEP occurs about 90mins after falling asleep. Your eyes move rapidly from side to side behind closed eye lids. There is a mixed frequency of brain wave activity occurring- similar to that seen when awake. Breathing is fast and irregular. Your heart rate and breathing rate reach near that of waking levels and most of your DREAMING occurs during REM sleep.
As you age your need for sleep and your patterns of sleep change. The amount of sleep required varies between individuals. Babies need the most sleep (16-18hrs a day). School children and teenagers need up to 9.5hrs and most adults need 7-9hrs. After the age of 60, sleep tends to become shorter, lighter and has many awakenings.
SLEEP MECHANISMS
There are 2 main biological mechanisms:
Circadian rhythm controls the timing of your sleep causing you to feel sleepy at night and to wake up in the morning without an alarm. The body has a biological clock that is based on a 24hr day and controls most circadian rhythms. These rhythms affect the body’s wakefulness, temperature, metabolism and release of certain hormones. These circadian rhythms synchronise with environmental factors such as light and temperature, and actual time of day.
Night shift workers often have difficulty sleeping when they go to bed and have trouble staying awake at work. This is due to their natural circadian rhythm and sleep-wake cycle being disrupted.
Circadian rhythms are out of sync in jet lag. This is due to a mismatch between the body’s internal clock and the actual clock.
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Sleep-Wake Homeostasis
keeps track of your need for sleep. It will remind the body to sleep after a certain time and it regulates the intensity of sleep. The drive to sleep increases every hour you are awake. If you have less sleep at night than your body needs, the drive to sleep gets stronger and causes longer and deeper sleep.
Various things can influence sleep-wake needs. These include:
- Medical conditions
- Medications
- Stress
- The sleep environment
- When you eat and drink
- Exposure to light. Cells in your eyes process light and tell your brain if it is day or night. It is possible to advance or delay our sleep-wake cycle. Exposure to light makes falling asleep more difficult and also makes it harder to return to sleep once awakened. This can be an issue if you look at your phone or a tablet prior to going to sleep.
According to Professor Russell Foster (Prof of Circadian rhythm, Oxford) phone light doesn’t significantly affect circadian rhythm. The theory being photoreceptors are maximally sensitive to blue light, we could be affected by blue light of screens. However human photoreceptors need really quite bright light to get activated to affect circadian rhythm, at a minimum of 100 lux (and that won’t do much, you need more like 400) and a screen is only 30 lux. In the famous iPad experiment, light from a screen only affected sleep onset by about 10 minutes. The major problem is the mental stimulation of the content people look at. Turning down screen brightness from its maximum can’t hurt. One theory why photoreceptors are maximally sensitive to blue light is that is what is in the sky mostly at dawn and dusk-so the photoreceptors are “dawn and dusk” receptors.
ANATOMY OF SLEEP
A part of the brain called the hypothalamus contains nerve cell groups that act as control centres affecting sleep and arousal. The brain stem - at the base of the brain - communicates with the hypothalamus to control transitions between wakefulness and sleep. A brain chemical known as GABA is produced by sleep promoting cells. It reduces the activity of arousal centres in the hypothalamus and the brain stem. The thalamus is active during REM sleep and sends images, sounds and other sensations to the brain cortex. It is these that fill our dreams.
The Pineal gland releases a hormone called MELATONIN. Melatonin keeps you asleep once the lights go out. Another hormone of importance is ADENOSINE.
Adenosine supports sleep drive and caffeine counteracts sleepiness by blocking the actions of adenosine.
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CHEMICAL SIGNALS TO SLEEP
Nerve cells (neurones) that promote sleep are in clusters in many areas of the brain and increase in activity as we are getting ready for bed. Neurotransmitters (nerve signalling molecules) are able to switch off the activity of cells that signal arousal or relaxation, GABA is associated with sleep, muscle relaxation and sedation. NORADRENALINE and OREXIN keep some parts of the brain active whilst we are awake. Other neurotransmitters that shape sleep include:
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Sleep problems are very common and can occur for a variety of reasons:
- Age
- Medical reasons- a sleep disorder
- Emotional reasons- stress and worry
- Unhelpful surroundings-sleeping environmental problems
- Disrupted sleep routines, such as shift work or jet lag.
- Being a parent or a carer
- Taking medication
- Coming off medication
- Recreational drugs
- Alcohol
- Working nights/shifts
- Current/past trauma
- Mental health issues- anxiety (racing thoughts. Panic attacks), Depression (this may also cause one to sleep too much), flashbacks from previous trauma, paranoia, psychosis, mania (you may not feel tired).
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If you are having problems sleeping you might be:
- More anxious, depressed or suicidal
- Feeling isolated
- Struggling to concentrate
- Feeling irritable
- Lacking energy
- Having difficulty living day to day life
- Affected by other health problems as well as mental health
Sleep QUALITY is not the same as QUANTITY of sleep. Quality is at least as important as quantity. Good quality of sleep allows you to form or maintain pathways in your brain that let you learn and create new memories, concentrate and function as well as you can.
Whilst you are asleep, your brain and body are still active. Sleep removes toxins that build up in your brain when you are awake.
Sleep is vital and affects almost every type of system in the body- from the brain, heart and lungs, to metabolism, mood, immune function, and disease resistance.
Treatment of sleep problems
Is sleeping your main problem, or is there another problem which may be causing you to have difficulty sleeping?
PROBLEM=worrying about not getting enough sleep. Worrying will just make it worse.
Thoughts such as “I’ll be shattered tomorrow”, or “I’ll never get to sleep” may run through your mind, leading you to feel tense and anxious and less likely to drop off to sleep. This in turn leads to a vicious circle with worrying thoughts about not sleeping leading to poorer sleep.
SOLUTION=Try to relax and clear your mind. You know that eventually you will fall asleep. Try laying calm and relaxed in bed and don’t keep on looking at the time. Have a daydream instead about something pleasant like a relaxing holiday. Imagine the sights, sounds and smells. Focus on breathing deeply through your nose and out with a nice long breathe via your mouth. Focus on your breathing. If your mind wanders- refocus on nice deep breathes. Deep muscle relaxation can also be helpful. Start from the toes and progressively tighten and then relax each muscle group in turn. Focus on the relaxed feelings as they begin to spread through the body.
Tom Middleton’s sleep CD is an example of a recording available to assist sleep
“SLEEP BETTER” Soundscapes to enhance sleep quality https://www.amazon.co.uk/Sleep...
CBT-I (Cognitive Behavioural Therapy for Insomnia)
CBT-I comprises eight sessions, each designed to address different aspects of insomnia
1. Introduction to the sleep diary – by keeping a sleep diary we can help identify both helpful and unhelpful patterns. It will also help us identify the best sleep schedule for you
2. Sleep rescheduling – we aim to look at the best sleep and wake times to try to get you back into a sleep routine whilst reducing unwanted time awake in bed
3. Stimulus Control – this session helps you to manage the worry and frustrations associated with being awake in bed during the night
4. Sleep Hygiene – this session looks at how your daytime and night time routines and behaviours, as well as your sleep environment, can impact on the sleep you are getting so we can maximize the opportunities for sleep
5. Cognitive Control – we aim to help manage the racing mind at night by putting the day to bed before you go to bed
6. Distraction Techniques – techniques that you can use if you are in bed and are awake to stop you from having lots of intrusive thoughts
7. Other Cognitive Techniques – this session looks at any additional techniques you might require to help manage the worry, stress and anxiety that builds up during the night if you are awake
8. Review and Relapse Prevention – this session focusses on ways to protect your sleep in the future and how you can best manage your sleep
PROBLEM=Needing to go to the toilet in the night. Are you up several times needing to empty your bladder?
SOLUTION=There may be a medical reason for this and the solutions vary depending on the problem. Bladder retraining can be of use, as can restricting caffeine and fluid late at night. Seek medical advice to assist you.
PROBLEM=Are you in a lot of pain? Does pain wake you or stop you getting off to sleep?
SOLUTION=Your GP may be able to help- seek advice. Deep muscle relaxation can help with pain- as being tense can make your pain worse.
PROBLEM= Have you experienced a loss or bereavement recently?
SOLUTION=Try not to worry about disrupted sleep patterns as it is very common to have disturbed sleep following a bereavement. Your sleep pattern should return to normal in time. Relaxation techniques may help. Talking to a friend, a counsellor or your GP may be of benefit.
PROBLEM=Anxiety, depression and stress all can affect your sleeping habits. It may be that as soon as your head hits the pillow, your mind starts working overtime thinking of your problems/worries.
SOLUTION=If your mind is racing, try relaxation techniques, focusing on a relaxed image or on your breathing. Make your breathing deeper and slower. This breathing will reduce your heart rate and in turn reduce the hormone cortisol. Cortisol is released when we are anxious. Think calming happy thoughts as it should help you sleep. Anxious worrying thoughts keep you awake.
If worry is a big problem for you, write down in a notebook each worry then take each worry in turn and ask yourself if there is anything you can do to solve each problem. Make a plan for when you are going to deal with that problem. Try setting aside 30 minutes of “worry time” a day. When you next start to worry, remind yourself to save until your next “worry time”.
PROBLEM=Sleep apnoea- snoring loudly, pausing and gasping frequently in the night
SOLUTION =Lifestyle changes. Losing excess weight, cutting down on alcohol, sleeping on your side. You may benefit from a GP referral to a sleep clinic.
GOOD SLEEP HABITS
Ensure a sleep-productive environment: Earplugs, blackout blinds, eye mask, hot water bottle, bed socks. If your partner is keeping you awake, a spare room may be of use.
Avoid anything that contains caffeine taken near to bedtime e.g. coffee, tea, hot chocolate, cola. Avoid these within 6 hrs of going to bed, or have it decaffeinated. A malty drink may aid length of sleep and reduce broken sleep.
Nicotine is a stimulant. Avoid smoking last thing at night. Aim to have your last cigarette at least 4hrs before bedtime. NB nicotine patches and gum can also affect sleep adversely.
Medicines and other drugs can act as stimulants and so affect sleep e.g. asthma drugs, migraine drugs.
Avoid large amounts of alcohol as this affects sleep quality.
Get up and go to bed at the same time each day i.e. consistency.
Don’t nap during the day.
Only go to bed if you feel tired.
Pre-sleep routine: try to unwind and prepare for sleep an hour before getting into bed. Dim lights, avoid blue light from computer screens and laptops/mobile phones etc. Blue light emitted from electronic devices inhibits melatonin (the hormone that helps you sleep).
Aromatherapy oils and pillow mist and some calming music can help prepare for sleep.
A nice relaxed warm bath.
Exercise during the day, but avoid exercise too near to bedtime.
If you are troubled with insomnia, take a warm shower during the night. As your body temperature cools after the shower, your sleep hormones become active, and you should eventually drift off to sleep.
If you have not fallen asleep within 20mins, get up. Listen to relaxing music, read a relaxing book or watch something boring on the TV until you feel sleepy.