sleep physiology

Question 1

which sleep stage is towards the end of the night and has similar characteristics to wakefulness?

Answer 1

REM sleep

Question 2

Which muscles are NOT profoundly atonic during REM sleep?

Answer 2

extra ocular muscles and diaphragm

Question 3

What is the main function of REM sleep?

Answer 3

mainly for early brain development (important in childhood)

Question 4

Why is thermal regulation impaired during REM sleep?

Answer 4

increased cerebral blood flow

Question 5

Which type of sleep occurs at mainly at the start of the night and is a profound state of relaxation?

Answer 5

non-REM sleep

Question 6

What are the findings during NREM?

Answer 6

synchronised, rhythmic EEG activity
partial relaxation of muscles
reduced cerebral blood flow
reduced HR, BP and tidal volumes

Question 7

You can only dream during REM sleep. T/F?

Answer 7

FALSE - can dream in both types
NREM -> strong emotional link but can’t remember what happened; prominent single image occurs before you wake up.
REM -> illustrative-narrative dream

Question 8

Name the 3 critical processes for sleep onset.

Answer 8

1. “homeostatic” response
2. emotional response
3. circadian rhythm

Question 9

The effects of sleep deprivation are mostly prefrontal… what does this affect?

Answer 9

Impairs alertness but not old and well-rehearsed tasks, routine behaviour, logic tasks.

become irritable, suspicious

Question 10

Visual hallucinations are a common sign of sleep deprivation. T/F?

Answer 10

FALSE - visual illusions can occur but no psychoses

Question 11

Which cellular process peak during sleep?

Answer 11

cell division; skin mitoses

Question 12

Sleep helps with tissue repair and muscle recovery. T/F?

Answer 12

FALSE
Helps with tissue repair
but no evidence of muscle recovery during sleep

Question 13

What is the suggested minimum acceptable length of sleep?

Answer 13

7-7.5 hrs

Question 14

What is parasomnia?

Answer 14

a disturbance of sleep

Question 15

What kind of parasomnia is sleep walking, sleep paralysis and bruxism?

Answer 15

non-REM parasomnia

Question 16

Describe REM parasomnias.

Answer 16

dreaming, much simpler behaviour, usually latter 1/3 of night

Question 17

Parkinson’s is associated with which type of parasomnia?

Answer 17

REM

Question 18

when are the 2 peaks of onset of narcolepsy?

Answer 18

15 and 36

Question 19

What is cataplexy and how common is it in narcolepsy?

Answer 19

loss of muscle tone with strong emotions e.g. anger, laughing
Present in 70% of patients

Question 20

what are hypnagogic hallucinations?

Answer 20

seeing things as you fall asleep

Question 21

Give an example of daytime sleepiness.

Answer 21

embarrassing situations, e.g. falling asleep into meals

Question 22

Describe the multiple sleep latency test.

Answer 22

4x 35-min naps scheduled 2hrs apart.
Record EEG, muscle activity & eye movements.
Measure time from start of daytime nap to the 1st signs of sleep (sleep latency).
Faster patient falls asleep, the more tired they are.

Question 23

What investigation can you do in narcolepsy but it isn’t sensitive or specific?

Answer 23

CSF hypocretin