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Sleep is a state of consciousness that happens every 24 hours. It is a period of rest and recuperation for the body and much needed ‘down time’ for the brain. People vary in the amount of sleep they need, depending on their age, lifestyle, diet, personality and environment.

Generally, we sleep less as we age and our sleep tends to be more broken. Newborn babies tend to sleep for around 16 hours out of every 24, while adults average eight hours and the elderly sleep a little less. Sleep is regulated by an internal ‘clock’, which is tuned by the day-night cycles (circadian rhythm).

When the sun sets, your brain starts to release ‘sleepy’ chemicals, until eventually you feel the need to retire for the night. In the morning, exposure to daylight prompts your brain to reduce ‘sleepy’ and release ‘awake’ chemicals. Sleep isn’t a static state of consciousness.

We all go through various distinct stages of sleep, over and over, every night. Generally, the brain moves from light sleep to deeper sleep and eventually to rapid eye movement, or REM, sleep. REM sleep occurs regularly, about once every 90 to 120 minutes.

Brain waves in REM sleep are faster than in non-REM sleep. REM sleep is associated with dreaming and with stimulation of the parts of the brain used for learning, while body repair and growth tends to happen during non-REM sleep. It is important to get the right mix of both REM and non-REM sleep to maintain your natural sleep cycle and help you wake rested and refreshed.

Sleep is a complicated state of consciousness, since it can be disturbed in so many ways. Some of the more common sleep complaints include: – refers to difficulties in getting to sleep or staying asleep. It is the most common sleep disorder in adults.

– a different time zone throws off the body’s internal clock, which takes a few days to reset.

Working night shift can mimic the symptoms of jet lag

– is muscle spasms of the legs that may wake up the sleeper. This is more common in the middle-aged and elderly. – is discomfort in the lower legs, which gets better with movement and gets worse later in the day makes the person need to move their legs or get up and walk around.

It is more common in males

– the sleeper tends to act out what’s happening in their dreams, which could mean punching or kicking. Some disorders such as sleepwalking, sleep starts and snoring often don’t require any treatment because they are harmless. Lifestyle changes can help relieve mild or occasional symptoms if they are causing an unwanted disruption to your life.

Insomnia, the most common form of sleep complaint, is a symptom, not a diagnosis, and, requires assessing and treatment of the cause (or causes) rather than the insomnia itself. Some of the more involved sleep disorders need to be treated at a sleep disorder clinic. While snoring alone may be harmless (benign snoring), it may indicate the presence of a more serious medical condition – obstructive sleep apnoea.

The body clock Sleep stages Common sleep disorders Insomnia Jet lag Narcolepsy Periodic limb movement disorder Restless legs Snoring Sleep apnoea Sleep starts Sleepwalking REM sleep behaviour disorder Treatment for sleep disorders Where to get help Your GP (doctor) Sleep Health Foundation Sleep disorder clinic / sleep specialist a sleep specialist is a medical doctor who has undertaken specialised training in the field of sleep medicine.

Key Points

  • Some of the more common sleep complaints include: – refers to difficulties in getting to sleep or staying asleep
  • the most common sleep disorder in adults
  • Working night shift can mimic the symptoms of jet lag
  • more common in the middle-aged and elderly
  • – is noisy breathing caused by a narrow throat and nose