Sleep Flashcards
What is sleep?
A normal, reversible, recurring state in which we lose the ability to respond to our external environment.
At which stage of the night is REM sleep?
Mostly towards the end of the night.
In REM sleep, is there more brain activity than in non-REM sleep?
Yes, it is similar to that seen in wakefulness.
Which muscles are not affected by the profound muscle atonia seen in REM sleep?
Ocular muscles
Diaphragm
What form of dreaming occurs in REM sleep?
Narrative dreaming
What do non-REM dreams involve?
A single image associated with intense emotion.
Which phase of sleep is thought to be dispensible?
REM sleep
Which drugs can abolish REM sleep?
Tricyclic antidepressants
What phase of sleep is most important - can be referred to as deep sleep?
Non-REM sleep.
What 3 factors control the onset of sleep?
Homeostatic response
Emotional response
Circadian rhythm
What is the circadian rhythm?
The ‘body clock’.
What is the function of the circadian rhythm?
Controls: Temperature Sleepiness Appetite Alertness Hormone secretion
Which cells are responsible for detecting light for the body clock?
Retinal ganglion cells
What does sleep deprivation affect?
Alertness
Does not impair ability at well-rehearsed tasks.
At which time of night is the risks of sleep deprivation greatest?
4am
What are parasomnias?
Conditions affecting sleep.
What are REM parasomnias?
Where muscle function is not lost in REM sleep.
It can be idiopathic, but also linked to dementia and PD.
What are the features of narcolepsy?
Daytime solemness
Cataplexy
Hypnagogic hallucinations
Sleep paralysis
How is narcolepsy diagnosed?
Overnight polysomnography
Multiple sleep latency test
What occurs in narcolepsy?
Patient falls asleep quickly, however enters REM sleep almost instantly.
Results in non-refreshing, expendable sleep only.
