Sleep

Question 1

What is the role of the suprachiasmatic nucleus?

Answer 1

Circadian pacemaker

Optic chiasm

Question 2

What are the stages of sleep?

Answer 2

• 90 mins each cycle
  1) Wakefulness - alpha rhythm
  2) N1 - theta, slow eye movements
  3) N2 - K complexes + sleep spindles
  4) N3 - delta
  5) REM

Question 3

How is sleep regulated?

Answer 3

1) Homeostasis - adenosine increases sleep pressure, chronotype changes with age
2) Circadian rhythm - clock genes, melatonin makes you sleepy, levels peak @ 4
3) Zeitgebers = enviro agent that provides stimulus or resets biological clock of organism e.g. light

Question 4

What is insomnia?

Answer 4

• Primary = isolated insomnia
• Secondary = due to co-morbid psychiatric disorder or medication, treating disorder doesn’t always improve sleep
• Chronic = reduced sleep quality/quantity, 3 x week for 3 + months

Question 5

How is insomnia treated?

Answer 5

• Sleep hygiene strategies
• Short term medication
• Sleeping tablets - Benzodiazepine receptor agonists, Melatonin
• CBT

Question 6

What is obstructive sleep apnoea?

Answer 6

Upper airway completely or partially blocked while sleeping

Question 7

How is obstructive sleep apnoea treated?

Answer 7

CPAP = continuous positive airway pressure

Question 8

What is restless leg syndrome?

Answer 8

• Constant urge to move legs at rest
• Temporarily relieved with activity
• Usually in evening
• Can be secondary to low iron levels - pregnancy
• Common as you get older - relate to dopamine levels

Question 9

What is periodic limb movements of sleep?

Answer 9

• Repetitive involuntary movements of limbs during sleep

- Related to dopamine

Question 10

What are pasasomnias?

Answer 10

Undesirable physical events or experiences that occur during entry into sleep, or during arousal from sleep

Question 11

What are the different types of parasomnias?

Answer 11

REM
- Nightmares

NREM

• Sleep walking
• Sleep eating/drinking
• Night terrors

Not specific to sleep stage

• Exploding head syndrome
• Sleep-related hallucinations

Question 12

What is hypersomnia?

Answer 12

Prolonged sleep duration + excessive sleepiness

Question 13

What is Narcolepsy?

Answer 13

• Excessive daytime sleepiness
• Involuntary sleep attacks
• Cataplexy (sudden muscle weakness causes by strong emotions)
• Sleep paralysis
• Hypnagogic/hypnopompic hallucination
• Low orexin

Question 14

What is Kleine-Levin?

Answer 14

• Episodic hypersomnia
• Hyperphagia - compulsive eating
• Hypersexuality episodes