There is considerable variance in normal sleep requirements. Common knowledge is that 8 hours of sleep per night are required. However many people need more or less sleep time than this amount.
For a healthy fit young person the typical ideal is 7.5-8 hours per night, with the time between attempting to sleep and falling asleep of half an hour. Wakefulness during the period of sleep should be less than 5% of the time, so again less than half an hour.
Our busy modern lifestyles often don’t leave room in the schedule for sleep durations of this length. Often this is not a major problem, humans can stay awake without issue for 16-18 hours, however a feeling of sleepiness is a function of instability in the wake-sleep cycle.
Sleep experts are often questioned as to how to fall asleep quickly or how to avoid waking up during the night or how to stop snoring. These questions may indicate an underlying sleeping problem.
Alarm clocks and late nights may allow us to live our modern lives as we like, but at the risk of developing sleep debt, sleeping problems and frequently sleeping disorders.
A sleep disorder is any disorder which prevents, interrupts or disturbs sleep. They are very common, half the population report having some trouble sleeping every year while a quarter of the population report that they have trouble getting enough sleep. Snoring is perhaps the most common sleep disorder.
Before we answer the question of how to get a good nights sleep it is important to understand why sleep is important and what can cause sleep problems.
Sleep is divided into two stages. REM or rapid eye movement and non-REM sleep. REM is that period during sleep when dreaming occurs; it is also associated with physiological arousal. Physically the eyelids flicker. Typically REM sleep occurs for short durations of five minutes or so, lasting longer throughout a night of uninterrupted sleep.
Non-REM or slow wave sleep usually lasts for a much longer duration, between sixty and ninety minutes. The REM takes place in between these stages of slow wave sleep.
Slow wave sleep is associated with an increase in hormones and an increased cellular rate. It helps the body to prepare an environment that can maintain the bodies’ defenses, repair of cells and metabolism. Children, adolescents and pregnant women often require additional sleep for this reason.
Both REM and non-REM sleep is required on a regular basis as it helps to preserve recent memories, maintains and refreshes both physical and mental equilibrium and prevents neurotransmitter depletion. The benefits of a good nights rest regularly and generally uninterrupted through the night are clear. Any disturbance of this state, especially involuntarily is to be taken seriously, and medical help should be sought.
The body has a natural rhythm which is evident in the wake-sleep cycle. This cycle is part of the human function known as the circadian rhythm.
The circadian rhythm is a biological function found in humans, other animal and even plants. It is related to the 24 hour cycle of the day and is an internal clock usually governed by the natural light/dark day/night cycle. The human biological clock is located in the hypothalamus and pineal gland of the brain. These glands secrete melatonin in response to the natural rhythm of the day and to light sources which can affect these rhythms. Melatonin is an important hormone for sleep regularity, during day time there is less in the body while the dark of night time increases the production in the glands.
The production of melatonin is heavily dependant on the bodies circadian rhythm, hence a rapid change in time zone from air travel or a switch to shift work is often associated with the sleep disorder known as jet lag.
A sleep disorder often indicates other issues and can be the primary symptom for very serious problems. Depression, anxiety and stress can all manifest themselves this way. Treatment of these problems will often resolve the sleeping issue.
Medical professionals, when presented with complaints of lack of sleep will also look for signs of adverse reactions to over the counter or prescription drugs or even illegal drug abuse.
Obstructive sleep apnea is potentially the most serious cause of interrupted sleeping. Undiagnosed or treated sleep apnea is directly linked with a much higher rate of injury and death due to the lack of deep and beneficial sleep this disorder will cause.
There are a range of other sleep disorders which regularly effect the population.
-somina is the Latin root for “sleep” or “dream”.
Many of the disturbances and disorders that follow will be based on this root
Dyssomnias are a disturbance in the regular pattern of sleep.
Parasomnias are disorders which interfere with sleep due to abnormal dreams, behaviors, actions and emotion experienced while asleep.
Secondary sleep disorders are problems with sleeping associated with another underlying problem. The sleep disturbance is a symptom rather than the primary cause for concern.
Some common sleep disorders
(Source Murtagh (2003), “General Practice” McGraw Hill)
Dyssominas (problem with falling asleep)
- Primary Insomnia
- Nocturnal myoclonus
Excessive somnolence (excessive sleep)
- Primary hypersomnia
Breathing related sleep disorder
- Obstructive sleep apnea (or apnoea)
- Central sleep apnea
- Central alveolar hypoventilation syndrome
Circadian rhythm sleep disorder
- Jet lag
- Shift Work
- Delayed sleep phase
- Nightmares (dream anxiety) Disorder
- Sleep Terror Disorder
- Sleepwalking disorder
Secondary Sleep Disorder
- Medical Condition disorder
- Mental Disorder
- Substance Abuse
Sleep specialists are a relatively new field in medicine. Certified sleep experts can be found by contacting the American Academy of Sleep Medicine or the appropriate medical directorate in your country. Observation in a sleep lab or sleep clinic is often used to diagnose sleeping disorder issues, alternatively the patient may construct their own sleep calendar to develop accurate records of the sleeping troubles.