Sleep Disorders

Question 1

Where is melatonin released from?

Answer 1

Pineal gland

Question 2

What is the role of the suprachiasmatic nucleus?

Answer 2

To stimulate the pineal gland to release melatonin

Question 3

What increases concentrations of melatonin?

Answer 3

Darkness

Question 4

When are cortisol levels highest?

Answer 4

In the morning

Question 5

What constitutes a sleep disorder?

Answer 5

Conditions that affect the ability to sleep well on a regular basis and interferes with daily life

Question 6

What is insomnia?

Answer 6

Difficulty falling or staying asleep

Question 7

What is sleep apnoea?

Answer 7

Breathing repeatedly starts and stops during sleep

Question 8

What is hypersomnia?

Answer 8

Exhaustion even after a full nights sleep

Question 9

What is narcolepsy?

Answer 9

Irregular sleep wake cycles

Question 10

What is parasomnia?

Answer 10

Unusual behaviour during sleep

Question 11

What are results of insomnia?

Answer 11

Irritability
Mood changes
Poor concentration
Memory defects
Increased appetite
Impaired creative thinking, verbal processing and problem solving

Question 12

Describe the rodent model of insomnia

Answer 12

A rodent is placed on an inverted flowerpot with a smaller diameter than their body length. The flowerpot is placed in cold water
At the onset of REM sleep, muscle relaxation occurs so the mouse falls into the cold water and wakes up

Question 13

What is fatal familial insomnia?

Answer 13

A genetic condition which results in an inability to reach REM sleep which causes dementia

Question 14

What is the mortality rate for fatal familial insomnia?

Answer 14

100%

Question 15

What neurological changes are seen in fatal familial insomnia?

Answer 15

Changes in the spongiform cortex

Thalamic atrophy

Question 16

What is the genetic link to fatal familial insomnia?

Answer 16

Heterozygous D178N mutation, with methionine at position 129 of PRNP gene

Question 17

How may sleep disorders be diagnosed?

Answer 17

Polysomnography

Wrist actigraphy

Question 18

Describe polysomnography

Answer 18

The patient sleeps with a number of devices attached that measures eye movement, brain activity, nasal air flow, breathing and blood oxygen saturation

Question 19

Describe wrist actigraphy

Answer 19

A device is worn on the non-dominant hand to determine time spent sleeping in each stage of sleep

Question 20

What is the link between schizophrenia and sleep?

Answer 20

Schizophrenic patients saw a shift in sleep onset, melatonin peak and sleep offset which may contribute to hallucinations and psychosis

Question 21

Which hormones promote sleep?

Answer 21

GABA, melatonin, adenosine

Question 22

Which hormones promote wakefulness?

Answer 22

Noradrenaline, dopamine, serotonin, histamine, acetylcholine, hypocretin

Question 23

What may be used to treat insomnia?

Answer 23

Benzodiazepines
Benzodiazepine receptor agonists
Antidepressants
Hypocretin antagonists
Melatonin agonists
Anticonvulsants

Question 24

What is the mechanism of a benzodiazepine or benzodiazepine receptor agonist?

Answer 24

Binding to Alpha-1 GABA subunit to increase sleep duration

Question 25

Give an example of a benzodiazepine?

Answer 25

Clonazepam, clorazepate, diazepam, lorazepam, temazepam

Question 26

Give an example of a benzodiazepine receptor agonist

Answer 26

Zolpidem, zaleplon, zopiclone, eszopiclone

Question 27

What does drug treatment for narcolepsy aim to do?

Answer 27

Control daytime sleepiness and cataplexy

Question 28

How does modafinil treat narcoleptic symptoms?

Answer 28

Mechanism unknown

Thought to be a dopamine reuptake inhibitor which increases hypocretins and histamines

Question 29

How does methylphenidate treat narcoleptic symptoms?

Answer 29

Noradrenaline-dopamine reuptake inhibitor

Question 30

How does sodium oxybate treat narcoleptic symptoms?

Answer 30

Mostly unknown

Interacts with GABA B receptors