Sleep Disorders (Part 1) Flashcards
What is sleep?
A normal, recurring reversible state in which there is a loss of ability to respond to the external environment
When sleeping, why are we not conscious?
We are not fully aware of self and the environment
When sleeping, why are we not unconscious?
We can respond when stimulated
When does a) non-REM and b) REM sleep occur?
a) at the start of the night b) at the end of the night
What will an EEG show in a) non-REM and b) REM sleep?
a) synchronised, rhythmic activity b) fast activity
What happens to the muscles and cerebral blood flow in non-REM sleep?
Partial muscle relaxation and decreased cerebral blood flow
What happens to the heart rate, blood pressure and tidal volume in non-REM sleep?
All reduced
What does an MRI of REM sleep show?
Increased brain activity, similar to wakefulness
What happens to the muscles in REM sleep? What are the exceptions to this?
Atonic, except the diaphragm and extra-ocular muscles
In which sleep stage would you have a) narrative dreaming and b) some non-narrative images (emotive)?
a) REM sleep b) non-REM sleep
What happens to the cerebral blood flow in REM sleep?
Increased
3/4ths of all sleep in young adults is which type?
Non-REM
Which type of sleep is deep sleep?
Non-REM
Which stage of sleep is the essential part?
Non-REM
After sleep loss, how much of that is usually regained?What type of sleep is regained?
1/3rd / non-REM
What is the main purpose of REM sleep?
Early brain development
What is a common drug that reduced REM sleep with no effect?
Tricyclics
How many hours a day do neonates spend asleep? What proportion is non-REM/REM?
16 hours, 50/50 REM and non-REM
What happens to the % of REM sleep in the first decade of life?
It decreases
What are some features of sleep patterns in the elderly?
Increased awakenings, reduced REM latency, reduced total sleep time, daytime napping
What factors are responsible for controlling sleep?
Biology and physiology (Circadian rhythm)
Which age groups have a) an advanced sleep pattern b) a delayed sleep pattern?
a) Children and the elderly b) adolescents
When are the two peaks of sleepiness?
Between 2-4am and 1-3pm
What happens biologically during non-REM sleep?
Protein synthesis, cell division and growth
What happens biologically during REM sleep?
Consolidation of memories and possible deletion of unnecessary ones, and maintains immunocompetence
How long does a normal Circadian rhythm last?
25 hours
What is the relationship between sleep and exercise?
There is no muscle recovery during sleep so in theory lack of sleep should not stop people from exercising. However, sleep does help with tissue repair and growth hormone release.
The function of sleep is to allow time for what to rest?
Brain cortex
The effects of lack of sleep are commonly prefrontal and may include what?
Irritability/suspicion, visual illusions, microsleeps and concentration lapses, impaired alertness
Does lack of sleep effect old, well-rehearsed tasks and routine behaviours?
No
Why would sleep deprivation be most likely to kill you?
Car crash
Most studies suggest we need how many hours of sleep per night?
7-8
A mid afternoon nap of 15 minutes is the equivalent of how many night minutes?
90
