Sleep and Perception: Sleep Flashcards
What is defined at sleep insufficiency?
Less than 7 hours of sleep
How is sleep divided into 2 halves?
Core sleep: First 5 hours. Core sleep is the essential part of the sleep and is mainly slow wave sleep. This type of sleep is mostly composed of stages 3 and 4 on non-REM sleep (NREM 3-4). Core sleep is obtained during the first three sleep cycles and the remainder of the night sleep is considered optional sleep. It also is composed half of REM sleep.
Optional Sleep: Next 2+ hours. Mostly stage 2 &1
What are the different stage of NREM sleep?
Non-REM sleep is ordered from stages 1-4.
Stage 1 and 2: Acutely awake with a fast series of low amplitude brain waves
Stage 3 and 4: Slow deep wave. It is deeper sleep. This is often associated with dreams and the dreams you remember.
What was the Bunker Study?
Individuals were taken into a tunnel in Switzerland. They were able to then acclimatise. After which they were taken of everything that would indicate light or time. They were then allowed to sleep any time they like and be active at any time. They then settled down in a rhyme. A circadian rhythm. It is phase shifted by the average of an hour. The biological system (ultradian) that monitors time, is around 25 hours.
How many years does an individual spend sleeping?
25 years and 5 years in dream state
How does the proportion of time we spend in REM sleep change as we age?
It decreases
Sleep over a lifetime shows new-born’s sleep for around 16 hours a day and spend half of their sleeping time in REM sleep. A foetus, halfway through development, spends nearly all their time in REM sleep. REM sleep seems to be about organisation of the neuronal system in the brain. The proportion of REM sleep declines as we age. This may be due to the amount of activity – we become less activite and the relationship between activity and resting time become more blurred. By the age of 40, most spend very little in stage 3 or 4. There is also a reduction in parasomnias – which are associated with stage 3 and 4. Parasomnias include sleep talking, sleep walking and night terrors. As a result as we age, the proportion of time spent in REM sleep decreases, the proportion of time we spend in core sleep decreases (stages 3 and 4) and the amount of time we sleep decreases.
What is sleep latency?
Sleep latency – how long did it take you to get to sleep before you went to sleep. Latency is the time between setting up a behaviour and the initiation of the behaviour. Loss of sleep is a somatic indicator/marker for depression.
How can we monitor sleep?
Sleep logs can be used to map behaviour. It can give an indication between problematic behaviour and sleep; giving strategies for intervention.
In terms of monitoring movements during sleep you can use a mobile phone sleep app, video camera or tilt sensors. People do not move during REM sleep – they move before and after bursts of REM sleep. Movement during sleep is expected, common and necessary.
When do dreams occur?
While dreams are more common in REM sleep, they are not exclusive to REM sleep – typically stage 2 sleep (may remember these more). REM sleep dreams are twice as long, more vivid and longer.
What is a lucid dream?
A part of the dream in which we become aware you are dreaming. Experienced lucid dreamers can affect their dreams and characters within them. In sports you can imagine certain motor movements and so train yourself. In lucid dreams, some can even perform these situations.
What is the mean sleep duration?
7.75 hours
There is little variation though – you can capture the majority of the population between 6 and 9 hours.
What are micro-sleeps?
Microsleep refers to periods of sleep that last from a few to several seconds. People who experience these episodes may doze off without realizing it. Some may have an episode in the middle of performing an important task. It can occur anywhere, such as at work, at school, or while watching TV.
What is the prevalence of insomnia?
30% of the population have insomnia. 33% of the 30% of people with insomnia, have it so severe that they seek clinical attention (10%).
What are the causes of insomnia?
- It is rarely the main reason people go to see the doctor. Many doctors prescribe hypnotics – pharmaceuticals with sleep inducing properties (there was 15.3 million in 2011).
Insomnia is almost always a secondary problem i.e. a symptom of something else. - Psychological problems (Depression and anxiety being the most common)
- Other medical disorders (e.g. pain)
- Social environment (misuse of alcohol, drugs – chronic alcohol misuse can cause insomnia)
What is the treatment of insomnia?
- Hypnotic drugs – many of which are addictive
- Sleep education (psychoeducation – knowing about sleep. Reassuring some insomniacs that they have had enough sleep to alleviate anxiety and depression which may in turn improve sleep)
- Sleep hygiene (e.g. behavioural changes
- Dealing with tension/intrusive thoughts – using relaxation and cognitive approaches e.g. counting sheep
