Neuro Exam 4: Sleep

Front 1

What are the four stages of sleep?

Back 1

Stage N1: aka drowsiness; reduced alpha rhythm; some theta; mild decreased in EMG; slow roving eye movements
Stage N2: increased theta, vertex waves sleep "spindles"; mild decrease in EMG; no eye movements
Stage N3: high amplitude delta; mild decrease in EMG; no eye movements; some poorly recalled dreams, most parasomnias
R(or REM): low amplitude, mixed frequency PGO spikes; dramatic decrease in EMG (paralyzed --except eye,ear,respiration); bursts of rapid eye movements; increased physiologic activity; no regulation of body temp; penile erection; report dreams if awakened

Front 2

What does a sleep cycle consist of?

Back 2

1. N1 followe sequentially by stages N2 and N3 and reversing sequentially to stage N2.
2. First REM cycle about 90-100 min after falling asleep
**So each sleep cycle lasts about 90 minutes.
**Stage N3 occurs early in the night and more REM intervals late in the night

Front 3

How often are sleep cycles repeated through the night?

Back 3

4-6 times
-as night progresses, REM periods lengthen and N3 stage shortens within each cycle

Front 4

How much does each stage account for in total sleep time?

Back 4

N1: 5-10%
N2: 50-60%
N3: 10-20%
REM: 20-25%

Front 5

Describe how sleep changes over the lifetime?

Back 5

-Sleep shortens progressively with age (16 hrs infants, 8 hrs young adults, less in elderly)
-Distribution of sleep periods throughout 24-hour day changes with age
-Sleep stage patterns undergo age-related changes

Front 6

What happens if deprived of REM sleep?

Back 6

-There is no ill effect, thought there will be a rebound increase in REM sleep when allowed to dream again

Front 7

What is narcolepsy?

Back 7

1) Sleep attacks: suddenly go into REM sleep when should be awake (also have excessive daytime sleepiness present all day, every day)
2) Cataplexy: suddenly turn on REM sleep-paralysis system when awake
3) Sleep paralysis: wake up paralyzed longer because REM sleep-paralysis system is delayed in shutting off
4) hypogogic hallucinations: suddenly have dream imagery with sleep attack
*Have marked reduction of hypocretin-containing neurons and low levels of hypocretin in CSF

Front 8

What is REM behavior disorder?

Back 8

-Intermittent loss of general muscle paralysis of REM sleep which leads to complex motor activity associated with dreaming
-Most common in older men who have or will develop a neurodegenerative disorder than includes parkinsonism

Front 9

What is restless legs syndrome (RLS)?

Back 9

-Unpleasant sensation in legs at rest producing irresistiible need to keep legs in motion
-Associated with paresthesias/dysesthesias
-Symptoms worse at rest, relived by activity, worse at evening/night

Front 10

What are the three types of sleep apnea syndrome (SAS)?

Back 10

1) Obstructive: blockage of airflow at level of pharynx (most common)
2) Central: failure of CNS to stimulate diaphragm and intercostal muscles (more common in those with heart disease)
3) Mixed: due to central apnea component followed by obstructive component

Front 11

What are the factors that contribute to sleep apnea syndrome?

Back 11

Obesity, large tongue, enlarged tonsils, long uvula, long soft palate, micrognathia, retrognathia, narrow face, and nasal congestion

Front 12

What is primary insomnia?

Back 12

-Greater than one month of difficulty initiating sleep, difficulty maintaining sleep, or non restorative sleep
-Causes significant distress