Flashcards in Sleep Deck (30):
1
What is sleep?
A normal, recurring, reversible state
2
When do you enter NREM sleeo?
Start of night; 3/4 of sleep for young adults is NREM
3
What is NREM sleep?
Synchronised, rhythmic EEG activity, partial muscle realaxation, reduced cerebral blood flow, reduced HR, BP and tidal volumes
4
Do you dream in NREM sleep?
Yes; non-narrative
Wake up with a strong emotion but can't quite remember what the dream was aobtu
5
When do you enter REM sleep?
End of night
6
What is REM sleep?
EEG shows fast activitiy, fMRI shows increased brain activity
Atonic muscles (except diaphragm and extraocular muscles), cerebral blood flow increased, impaired thermal regulation
7
Do you dream in REM sleep?
Yes; narrative dreaming. Muscles paralysed so you don't act out dreams
8
Which part of sleep is most important?
Deep sleep; only part of lost sleep regained after sleep loss
Allows the cortex to recover after a busy day
9
What is the function of REM sleep?
Early brain development; substitute for wakefullness
10
Do you sleep less or more as you get older, and what type of sleep do you lose?
Less
REM sleep falls, REM latency increases
11
What are the 3 mechanisms that control sleep?
Homeostatic
Emotional
Circadian rhythm
12
What is the circadian rhythm important for?
Sleep-wake
Appetite
Hormone secretion
13
What biological processes occur during NREM sleep?
Protein synthesis
Cell division and growth
14
What biological processes occur during REM sleep?
Consolidates memory
Deletes unnecessary memory files
Maintains immunocompetence
15
When are the 2 peaks in sleepiness?
4am
2pm
16
How many hours does the normal circadian rhythm last?
25 hours
17
What is the impact of light on circadian rhythms?
Non-rod and non-cone cells project to suprachiasmatic nucleus to reset the body clock every morning
18
What occurs in sleep deprivation?
Irritable and suspicious
Visual illusions
Microsleeps and concentration lapses
19
What can you still do well even in sleep deprivation?
Prefrontal;
Old and well rehearsed tasks
Routine behaviour
Logic tasks
20
What tasks are not performed well in acute and chronic sleep deprivation?
Understanding complex situations and ignoring irrelevancies
Assessing risks and consequences
Dealing with the unexpected
Tracking events
Updating strategies
Communicating well
Showing lateral thought and innovation
21
How much sleep do we need?
7-7.5hrs a night
A mid afternoon nap of 15 mins is equivalent to 90 mins overnight
22
What are the different types of parasomnias?
NREM
Non-dreaming
Confusional arousals
Sleep walking
Sleep terrors and paralysis
Bruxism (teeth grinding)
Restless legs and PLMS
Complex dissociation
23
When will REM parasomnias manifest?
Latter 1/3rd of the night
24
Which condition is very closely associated with REM parasomnias?
Parkinson's disease
25
What is the presentation of narcolepsy?
Daytime sleepiness
Cataplexy
Hypnagogic hallucinations
Sleep paralysis
RBD
26
What is cataplexy?
Loss of muscle tone triggered by strong emotion
27
What are hypnagogic hallucinations?
Hallucinations occurring at sleep onset
28
What is sleep paralysis?
Inability to move upon falling asleep or awakening with retained consciousness
29
How is narcolepsy investigated?
Overnight polysomnography
MSLT; assess how quickly someone falls asleep and enters REM sleep
LP; CSF hypocretin levels with low levels consistent with narcolepsy
30