ECG, sleep and circadian rhythms

Question 1

Where do active inhibitory processes arise to cause sleep?

Answer 1

pons - reticular formation

Question 2

Where does the reticular formation send its activity?

Answer 2

thalamus and higher cortical areas

Question 3

What is the precursor of melatonin crucial for sleep production?

Answer 3

serotonin

Question 4

Damage to the SCN causes what?

Answer 4

disrupts sleep-wake cycle

Question 5

Where does melatonin release occur due to SCN activity?

Answer 5

pineal gland

Question 6

What does the hypothalamus release for wakefulness?

Answer 6

orexin/hypocretic

Question 7

When is orexin active and inactive?

Answer 7

active = awake

stop firing during sleep

Question 8

What can a defect in orexin cause?

Answer 8

narcolepsy

Question 9

2 main ways to assess consciousness levels

Answer 9

1 - behaviour, general alertness, speech etc

EEG

Question 10

EEG frequency increases with what?

Answer 10

neuronal excitation

Question 11

4 main types of EEG wave pattern

Answer 11

alpha, beta, theta, delta

Question 12

Alpha wave - what state?

Answer 12

awake, relaxed

Question 13

Alpha wave - EEG

Answer 13

high frequency, high amplitude

Question 14

Beta wave - what state?

Answer 14

awake, alert

Question 15

Beta wave - EEG

Answer 15

higher frequency, lower amplitude and asynchronous as waves cancel out

Question 16

theta - what state?

Answer 16

stressed, emotional, children

Question 17

Theta - EEG

Answer 17

low frequency, varied amplitude

Question 18

Delta - what state and EEG

Answer 18

deep sleep

low frequency, high amplitude

Question 19

Sleep cycle

Answer 19

1 - theta, eye moves, easily awoken 
2 - eye moving stops, sleep spindles 
3 - delta waves with spindles 
4 - delta 
5 - REM

Question 20

What stage can REM sleep look like on an EEG?

Answer 20

1

Question 21

Deep, slow wave sleep - physiological characteristics

Answer 21

reduced vascular tone and bp, decrease temperature and BMR and resp rate

Question 22

Inhibitory projections from where in REM sleep inhibit skeletal muscles?

Answer 22

pons –> spinal cord

Question 23

What muscles are not inhibited in REM sleep?

Answer 23

eye muscles

Question 24

What does sleep support?

Answer 24

neuronal plasticity, cognition, memory, immune system

Question 25

No sleep can lead to..

Answer 25

psychosis, irritability, sluggish, impairments

Question 26

2 types of insomnia

Answer 26

primary, no underlying problem, chronic

acute, secondary to bereavement, pain etc

Question 27

Night terrors - explain

Answer 27

children wake up in a shock with eyes open, not remembered the next morning

Question 28

What stage of sleep does nightmares occur in?

Answer 28

REM