Night Owls and Early Birds: Human Sleep patterns explained by psychiatrist Dr Magula.
A good night’s sleep is when you fall asleep quite easily, do not fully wake up during the night, do not wake up too early, and feel refreshed in the morning. Regularly having difficulty falling asleep or sleeping through the night is not normal for healthy people of any age. However, not everyone needs the same amount of sleep. The quality of sleep is different in different phases of life. Young children and older people sleep more lightly than adults and teenagers. The length of time spent in deep sleep phases changes over a person’s lifetime. Babies and toddlers need to sleep a lot more than older children and adults. By the time they reach the age of five, most children have the typical sleep patterns of an adult: they are awake during the day and then sleep through the night. The amount of time spent sleeping gradually decreases until the age of 80.
The body’s master clock, located in the brain, produces and regulates our circadian rhythms (sleep-wake cycle), which help determine sleep patterns for 24 hours.
Environmental signals, such as daylight and darkness, affect circadian rhythms, too. In the normal adult, there are two main stages of sleep that alternate at about 90-minute intervals. Rapid eye movement (REM) sleep can be roughly described as when the brain is active and the body is paralyzed (except for eye movements, middle ear ossicles, and respiration). In non-rapid eye movement (nonREM or NREM) sleep, the brain is less active, but the body can move.
When measuring total sleep time, sleep is considered to start when you close your eyes to fall asleep. The period between first closing your eyes and entering phase 1 is known as sleep onset. Phase 1 is very light sleep, where you are drifting in and out of consciousness and are easily woken.
In phase 2, the brain’s functioning slows down, but there are still short bursts of activity. The first two phases of light sleep make up about half of the total sleep cycle.
Phases 3 and 4 are the deep sleep phases. You dream in phase 4. When this phase ends, you sleep more lightly again before a new full sleep cycle starts. Some people entirely or partially wake up after the sleep cycle ends, while others stay asleep until morning. Total sleep time ends when you wake up and then stay awake and get up.
Why is it that some struggle to wake up and others do not?
The key to waking up early and refreshed lies in the ability to fall asleep on time, maintain your sleep and wake up at the appropriate time after your required hours of sleep for your age. The requirements decrease over age, with babies needing around 12 hours of sleep, children 10 hours and by adolescence 8 hours and the elderly 6 hours of sleep. So if you struggle to fall asleep, you will struggle to wake up early and refreshed. These are the kinds of sleep complaints:
trouble staying awake (hypersomnia),
trouble sleeping (insomnia), and
abnormal sensations or behaviour during sleep (parasomnias).
These complaints often go together, e.g. people who have trouble sleeping may fail to get an adequate amount of normal sleep and have difficulty staying awake the following day.
Trouble staying awake – excessive daytime sleepiness– The most common causes of hypersomnia are insufficient sleep, medications, sleep apnoea (central or obstructive), and narcolepsy. Patients may not complain of sleepiness so much as its consequences, including fatigue, headaches, decreased energy, difficulty concentrating, irritability, or an auto accident (“falling asleep at the wheel”).
Insufficient sleep – Many people do not schedule sufficient time for sleep at night, and sleepiness is expected in the setting of sleep deprivation.
Sleep apnoea – A condition in which patients periodically stop breathing while asleep. There are two types of sleep apnoea- central and obstructive. The most common cause of sleep apnoea is due to temporary obstruction of the upper airway. The extreme changes in the concentrations of oxygen and carbon dioxide in the blood that develop after 1 minute or more without air rouse the sleeper, and a few noisy, choking gasps refill the lungs. Obstructive sleep aponia is the most common medical cause of excessive daytime somnolence. Of significant importance to the diagnosis is a history of apnoeic episodes during sleep. Usually, people are unaware of the episodes because they are brief, and arousal is only partial, so history must be obtained indirectly, typically from a spouse or roommate. Symptoms/signs that are common include loud snoring and pauses in breathing. Additional symptoms include gasping for breath during sleep, dull headaches, and automatic behaviours
Narcolepsy – Narcolepsy is a syndrome consisting of excessive daytime sleepiness and disordered REM sleep regulation, resulting in an intrusion of REM sleep components into NREM sleep and the waking state. For the narcolepsy-cataplexy subtype, the two most significant and consistent symptoms are excessive daytime somnolence and cataplexy (sudden loss of postural tone that occurs while the patient is awake but is otherwise identical to the atonia that occurs during REM sleep). The principal symptom is irresistible sleep attacks lasting 5- 30 minutes during the day. These attacks may occur without warning and at inappropriate times, typically precipitated by strong emotion, mostly laughter. The sleepiness that occurs in narcolepsy cannot be relieved by any amount of normal sleep. The atonia may involve only a single muscle group, or it may be generalized and lead to collapse; consciousness is preserved. Narcolepsy-cataplexy typically starts around adolescence; daytime sleepiness is most often the first symptom to appear, followed by cataplexy
Night terrors (Sleep Terror Disorder) – Night terrors are sudden, partial arousal from delta sleep associated with screaming and frantic motor activity. These episodes occur during the first third of the major sleep episode and begin with a terrifying scream followed by intense anxiety and signs of autonomic hyperarousal.
Is it possible to change from a night owl to an early bird?
Much of what you need to do to wake up on time start by planning your sleep schedule the day and the evening before Getting enough sleep is essential to your health and wellbeing. These are different ways to improve your sleep and prevent being a night owl unwillingly.
Keep your room quiet and dark. Use earplugs to cut noise. Keep out light with window blinds, heavy curtains, or an eye mask. Move any electronic devices out of your bedroom, or turn them off. Even the LED or LCD lights on TVs, tablets, and music players in your bedroom can hamper sleep. Don’t turn on bright lights if you need to get up at night; use a small night-light instead.
Avoid large meals within 2 hours of bedtime. If you are hungry, try a glass of milk.
Time your sleep right. Go to bed at about the same time every night. Try not to nap late in the afternoon. If you do nap, keep it short, just 10 to 15 minutes. A good time to nap is about 8 hours after you wake up.
Calm down before bedtime. Stop working on any task an hour before bedtime, especially those that include computers and devices. Try to keep your mind off worries or things that upset you once you’re in your bedroom. Avoid talking about emotional issues in bed.
If your pet moves around on your bed, you may wake up. Pets also can affect sleep if they contribute to any allergies you have.
Keep your room cool and well ventilated.
Save your bedroom for sex and sleep only. You might want to do other tasks in the bedroom, especially if you can’t sleep. Instead, go into another room or if you only have one room, get out of the bed and sit on your chair and desk and read a book until you feel sleepy, then only can you return to bed.
Practice relaxing. Flexing your muscles, imagining a calming scene, or meditating can help you unwind and get ready to sleep.
Don’t smoke. Nicotine is a stimulant, which can keep you up. So reaching for a cigarette near bedtime or in the middle of the night can ruin sleep.
Stop having caffeine 4-6 hours before bed. That includes coffee, cola, tea, and chocolate, and some over-the-counter medications, too. Cut back on caffeine gradually to help prevent headaches. Coffee can however be a good morning starter to keep you awake if you struggle to wake up.
No nightcaps. Alcohol may make you feel sleepy, but it doesn’t make for a good night’s sleep. As your body processes the alcohol, you may wake up more easily.