Chapter 9: WHAT IS SLEEP?

Question 1

What are the three mechanisms for studying sleep?

Answer 1

• EEG: Electroencephalogram
• EMG: Electromyogram
• EOG: Electro-Oculogram

Question 2

What are the characteristic of the wake state?

Answer 2

-Alpha activity: smooth, 8-12 Hz (relaxed state)
and/or
-Beta Activity: Irregular 14-20 Hz (arousal state)

Question 3

What is the activity like during stage 1 of sleep?

Answer 3

• Theta activity: 3.5-7.5 Hz
• NREM sleep
• Theta activity is intermittent during early stages of slow-wave sleep and REM sleep

Question 4

What is the activity during stage 2 of sleep?

Answer 4

• sleep spindles: short bursts of 12-14 Hz, make the transition with stage 3.
• K complex: sudden sharp waveforms
• NREM sleep

Question 5

What is the activity during stage 3 and 4 sleep?

Answer 5

• Delta activity
• Slow-Wave sleep
• Synchronized EEG during deeper stages

Question 6

What is the only difference between stages 3 and 4 of sleep?

Answer 6

• The amount of Delta activity
• Stage 3: 20-50%
• Stage 4: More than 50%

Question 7

What is REM sleep?

Answer 7

• desynchronized EEG activity
• dreaming
• rapid eye movements
• muscular paralysis

Question 8

What physiological activity occurs during REM sleep?

Answer 8

• Heart rate: sudden accelerations and decelerations
• Breathing: irregular
• Brain: more active

Question 9

What is REM sleep also called?

Answer 9

paradoxical sleep

Question 10

SUMMARY: What are the main characteristics of REM sleep?

Answer 10

• EEG desynchrony: rapid irregular waves
• Lack of muscle tonus
• Rapid eye movements
• Penile erection or vaginal secretion
• Dreams

Question 11

SUMMARY: What are the main characteristics of slow wave sleep?

Answer 11

• EEG synchrony: slow waves
• Moderate muscle tonus
• Slow or absent eye movements
• Lack of genital activity
• No data on dreams

Question 12

What activity is there in the prefrontal cortex during REM sleep?

Answer 12

• Low activity

- lack of organization and planning that occurs in dreams

Question 13

What activity is there in the extrastriate cortex during REM sleep?

Answer 13

• High activity

- Visual hallucinations while dreaming

Question 14

What activity is there in the striate cortex during REM sleep?

Answer 14

• Low activity

- Lack of visual input

Question 15

How do the cycles of an adult progress as the night goes on?

Answer 15

• 90 minute cycles

- As the night goes on, there will be less SWS and more REM sleep in each cycle