EEG, Sleep and Circadian Rhythm

Question 1

Which part of the brain controls sleep?

Answer 1

Reticular formation in the brainstem

Question 2

Which part of the brain is involved in the induction of sleep?

Answer 2

Suprachiasmatic nuclei (SCN) in the hypothalamus

Question 3

Which hormone produces feelings of sleepiness?

Answer 3

Melatonin

Question 4

Which hormone is required for wakefulness and where is it released from?

Answer 4

Orexon/hypocretin

Question 5

Which part of the reticular formation is responsible for wakefulness?

Answer 5

Ascending Reticular Activating System (ARAS)

Question 6

How are levels of consciousness assessed in an awake patient?

Answer 6

1) Assess behaviour, general alertness, speech content, reading, writing, calculating skills etc.
2) EEG

Question 7

What are the four types of waves seen on an EEG?

Answer 7

Alpha, beta, theta and delta

Question 8

What waves are most commonly seen on an EEG when a person is in a relaxed, awake state?

Answer 8

Alpha waves (high frequency, high amplitude)

Question 9

What waves are most commonly seen on an EEG when a person is alert and awake?

Answer 9

Beta waves (very high frequency, low amplitude)

Question 10

When are theta waves commonly seen on an EEG?

Answer 10

In children, during stress and frustration in adults and during sleep in adults and children (low frequency, varying altitude)

Question 11

When are delta waves seen on a EEG?

Answer 11

Deep sleep ( low frequency, high altitude)

Question 12

What is the 1st stage of the sleep cycle?

Answer 12

Slow wave, non-REM sleep, slow eye movement, light sleep, theta waves

Question 13

What is the 2nd stage of the sleep cycle?

Answer 13

No eye movements, frequency slows and sleep spindles (bursts of rapid waves)

Question 14

What is the 3rd stage of the sleep cycle?

Answer 14

Delta waves interspersed with short episodes of faster waves

Question 15

What is the 4th stage of the sleep cycle?

Answer 15

Exclusively delta waves

Question 16

What is the 5th stage of the sleep cycle?

Answer 16

REM sleep - dreams occur during this stage

Waves are very similar to those of someone who was awake

Question 17

What happens to BP, respiration and metabolic rate during deep sleep?

Answer 17

BP decreases
Respiration decreases
Basal metabolic rate decreases

Question 18

Can dreams occur during deep sleep?

Answer 18

They can but are rarely remembered

Question 19

What happens to HR and resp. rate during REM sleep?

Answer 19

They become irregular

Question 20

What happens when a person becomes sleep deprived?

Answer 20

Impairment of cognitive function, impairment of physical performance, sluggishness and irritablity

Question 21

Why is sleep important?

Answer 21

Sleep supports: neuronal plasticity, leaning and memory, cognition, clearance f waste from the CNS, conservation of body energy and immune function

Question 22

What is the definition of insomnia?

Answer 22

A chronic inability to obtain the necessary amount or quality of sleep to maintain adequate behaviour

Question 23

What effect do barbiturates have on sleep?

Answer 23

Depress REM and delta sleep

Question 24

When do night terrors occur?

Answer 24

In delta sleep