PDF - Sleep

Question 1

Progression into REM?

Answer 1

Progression “down” through stages 1, 2, 3, and 4 of NREM, then reverse “up” before first REM occurs

Question 2

What goes on in Stage 1?

Answer 2

1. Drowsiness

2. Early EEG slowing

Question 3

What goes on in stage 2?

Answer 3

1. Asleep but easily aroused

2. Unique sleep spindles on EEG

Question 4

What goes on in stages 3 and 4?

Answer 4

1. Sleep deeps, hard to arouse

2. Slowest (delta wave) EEG activity

Question 5

Progression of REM sleep?

Answer 5

• First REM period occurs 90 minutes after sleep begins
• Reoccurs every 90 minutes thereafter
• Lasts only a few minutes at first
• Subsequently lengthens in duration to an hour

Question 6

When is limb hypotonia maximal?

Answer 6

REM sleep

Question 7

What is seem in REM?

Answer 7

1. Limb hypotonia
2. Subtle twitches of face and limbs
3. irregular pulse and breathing
4. Horizontal, rapid, conjugate eye movements

Question 8

EEG in REM?

Answer 8

Similar to wake state

Question 9

Recall in REM?

Answer 9

• Recallable dreams occur in REM

- This stage is important for reinforcing memory traces

Question 10

What does lack of REM cause?

Answer 10

1. Anxiety
2. Hostility
3. Hallucinations
4. Amnesia

Question 11

Impact barbiturates on sleep?

Answer 11

Suppress REM

Question 12

Sleep changes with age?

Answer 12

1. Newborns sleep 15 hours daily
   - Frequent yet shorter periods
2. Elderly Sleep about 6 hours
   - More frequent drowsy periods
3. Percentage of REM falls from 50% in infants to 20% in adults
4. Slow wave sleep (stages 3 / 4) decreases with age
5. Stage 1 and 2 sleep increases with age

Question 13

Function of ARAS?

Answer 13

Important in arousal and wakefullness

Question 14

What does lesion in ARAS cause?

Answer 14

Persistent somnolence or coma

Question 15

Function Pontine REM center?

Answer 15

• Activates brain stem gaze centers responsible for rapid, conjugate eye movements during REM
• Induces hypotonia and increased autonomic activity

Question 16

What controls REM and NREM sleep?

Answer 16

• REM and NREM sleep are promoted by preoptic area of

ventrolateral hypothalamus

Question 17

What is hypothalamic suprachiasmatic nucleus?

Answer 17

“Biological clock”

• Controls circadian sleep-wake cycle
• Receives direct retinal input via optic chiasm, allowing environmental light stimuli to influence the “clock”

Question 18

Cardiopulmonary sequelae sleep apnea?

Answer 18

• Frequent sleep apneas create nocturnal hypoxemia which in turn cause spulmonary hypertension or cardiac
  arrhythmias

Question 19

Pathology OSA?

Answer 19

Upper airway obstruction despite contraction of diaphragm and chest wall muscles

Question 20

Pathology Narcolepsy?

Answer 20

• REM sleep occurring at inappropriate times

- Related to a deficiency of neurons in hypothalamus which release excitatory peptide hypocretin

Question 21

Features narcolepsy?

Answer 21

1. Narcoleptic attacks
2. Cataplexy
3. Sleep paralysis
4. Visual hallucinations when falling asleep or waking up.

Question 22

What is cataplexy?

Answer 22

Loss of muscle tone, for seconds - minutes in duration

• Often provoked by emotional triggers, such as an angry outburst, laughing at a joke or being “surprised”
• Slumps to ground because of REM hypotonia and may not speak well, yet breathes, stays awake, and recalls event

Question 23

What is sleep paralysis?

Answer 23

REM hypotonia transiently preventing getting out of bed on wakening

Question 24

Diagnosis narcolepsy?

Answer 24

Abnormally early onset REM as patient allowed to fall asleep several times (not in state of sleep deprivation)

Question 25

Utility modafinil?

Answer 25

Narcolepsy and somnolence from sleep apnea

Question 26

Rx cataplexy?

Answer 26

TCAs

Question 27

Definition insomnia?

Answer 27

Inadequate quantity and quality of sleep to maintain normal daytime behavior

Question 28

What is REM behavior disorder?

Answer 28

• Abnormality of REM sleep, where typically older male patients lack normal hypotonia of REM
• Appear to be “acting out” dreams to point of injuring themselves or their bed partner
• Often precedes onset of Parkinson’s disease or Lewy body dementia