Week 4- sleep and hypersomnolence

Question 1

What is sleep?

Answer 1

A normal, recurring reversible state. Loss of ability to respond to the external environment.

Question 2

Are you conscious or unconscious in sleep?

Answer 2

Neither. You are not fully conscious because you are not fully aware of yourself/environment. However you can respond when stimulated.

Question 3

Describe Non- REM sleep?

Answer 3

Makes up about 3/4 of sleep. Happens at the start of the night.

Question 4

Describe the EEG of NREM sleep?

Answer 4

Slower, rhythmic and synchronised EEG.

Question 5

Describe the muscles and blood flow in NREM sleep?

Answer 5

Partial muscle relaxation.

Reduced cerebral blood flow.

Question 6

Describe the heart rate, blood pressure and tidal volume in NREM sleep?

Answer 6

Reduced heart rate, bp and tidal volume.

Question 7

You can have dreams in both NREM and REM sleep. True or false?

Answer 7

True- however the dreams differ.

Question 8

Describe the dreams in NREM sleep?

Answer 8

Usually a strong emotional connection.

Usually a single image.

Question 9

Describe the dreams in REM sleep?

Answer 9

Usually a story or narrative.

Question 10

Describe the EEG of REM sleep?

Answer 10

Almost like wakefulness. Fast activity and an FMRI will show increased brain activity.

Question 11

What happens to the muscles in REM sleep?

Answer 11

they become atonic (lack muscular tone).

Question 12

Other physiological changes in REM sleep?

Answer 12

Increased cerebral blood flow and impaired thermal regulation.

Question 13

Which type of sleep is the most important?

Answer 13

NREM.

Question 14

Which part of sleep is regained after sleep loss?

Answer 14

Deep sleep. (NREM sleep). It allows the cortex to recover after a busy day.

Question 15

When is REM sleep important?

Answer 15

Important in early development.

Question 16

Which drugs suppress REM sleep?

Answer 16

Tricyclics.

Question 17

In infancy, what makes up the majority of sleep?

Answer 17

REM sleep.

Question 18

As you get older, the amount of NREM sleep decreases. True or false?

Answer 18

False. The amount of REM sleep decreases but the amount of NREM sleep remains the same.

Question 19

What physiological processes are said to occur in non REM sleep?

Answer 19

Protein synthesis, cell division and growth.

Question 20

What physiological processes are said to occur in REM sleep?

Answer 20

Consolidates memory and possibly deletes unnecessary ones.

Question 21

Can you control your sleep?

Answer 21

Nope- if your body wants to sleep, no matter the situation it will sleep.

Question 22

When are the two bouts of sleepiness in the body?

Answer 22

2-3 o-clock in the afternoon and 3-4 o clock in the morning.

Question 23

Different ages run on different body clock times. True or false?

Answer 23

True- babies run at an earlier body clock (go to bed earlier, wake up earlier). Young adults run at a later body clock.

Question 24

Why is there a dip at 3/4 o’clock in the morning?

Answer 24

Cortisol levels dip then.

Question 25

How long is the normal circadian rhythm?

Answer 25

25 hours. It runs to this and has to reset to 24 each day.

Question 26

NOTE- there are certain cues to say that you are awake. E.g. wake up, have breakfast. And certain cues to say you should be asleep, being in bed etc. Also light has a major influence. This is why when its dark in the winter you struggle to get up.

Answer 26

:)

Question 27

Is there a correlation between exercise and sleep?

Answer 27

No- no evidence of muscle recovery during sleep. However sleep does help with tissue repair.

Question 28

When people are deprived of sleep- it can lead to mood changes, why is this?

Answer 28

The cortex can’t fully relax when you are awake. If you are awake for too long it can lead to irritability and suspicion. You can also have visual illusions and concentration lapses.

Question 29

How does sleep affect prefrontal function?

Answer 29

Not affected.
Tasks that are old and well rehearsed will still be able to be done. However does impair your alertness and ability to think laterally.

Question 30

What is the minimum sleep per night to not be sleep deprived?

Answer 30

6-7.5 hours

Question 31

Why is chronic sleep deprivation an issue?

Answer 31

When you are chronically sleep deprived, you do not realise you are.

Question 32

What are parasomnias?

Answer 32

Broadly speaking there are two categories. Non REM and REM parasomnias.
When you go from sleep to wakefulness, the process takes seconds to minutes. Parts of your brain wake up before the others. E.g. memory tends to wake up late.
REM parasomnias- If they are kicking a football in the dream, they will be doing it in real life.
Non-REM- patient responds to dream emotionally.

Question 33

What is narcolepsy?

Answer 33

Daytime sleepiness- involuntary somnolence during eating/talking. May be severe and impossible to resist.
Cataplexy- loss of muscle tone, triggered by emotion
Hypnagogic hallucinations- hallucinations occurring at sleep onset.
Sleep paralysis- unable to move upon falling asleep or awakening with retained consciousness.
RBD- REM Sleep behaviour disorder.

Question 34

What investigations could you do into narcolepsy?

Answer 34

Overnight polysomnography
Multiple sleep latency test- how fast a patient falls asleep basically.
Lumbar puncture

Question 35

What will a lumbar puncture of a patient with narcolepsy show?

Answer 35

CSF can show low hypocretin levels.

Question 36

Can patients with narcolepsy drive?

Answer 36

They have to cease driving until things are controlled (about two years).