Week 10 Pt 2: Sleep And Waking

Question 1

What are circadian rhythms?

Answer 1

Physical, mental and behavioural changes that follow a roughly 25-hour cycle
Responds primarily to light and darkness in an organisms environment

Question 2

What is ultradian?

Answer 2

Shorter cycles

e.g. pulsatile release of pituitary hormones, apetite

Question 3

What is infradian?

Answer 3

Longer

e.g. ovarian cycle

Question 4

What does suprachiasmatic nucleus within hypothalamus have?

Answer 4

Input from retina via Ganglia cells which are responsive to light

Question 5

What do retinal rod and cones project onto?

Answer 5

Ganglia cells which form axons of optic nerve

Question 6

What does optic nerve axons have?

Answer 6

Light sensitive neurons (respond to blue light)

Question 7

What is suprachiasmatic nucleus?

Answer 7

master pacemaker

Question 8

What cells from outside the SCN exhibit circadian pattern?

Answer 8

Pituitary gland
Pineal gland
Outside brain: liver, lungs

Question 9

What is SCN?

Answer 9

Paired nuclei found within the hypothalamus

Question 10

What is the function of SCN?

Answer 10

Maintain circadian rhythms or biological pattern that follow 24 hour cycle

Question 11

What do cells of SCN contain?

Answer 11

Biological clock

Question 12

What does cells in SCN produce?

Answer 12

2 proteins:
Clock
BMAL1

Question 13

What does clock/BMAL1 promote the transcription of?

Answer 13

PER and CRY genes

Question 14

What happens when PER and CRY genes bind together?

Answer 14

Inhibit the transcription of their own genes

Question 15

SCN

Answer 15

PER and CRY proteins begin to degrade
Allow clock/BMAL1 to promote PER and CRY transcription again
Entire cycle takes about 24 hours

Question 16

What is found in the core region of SCN?

Answer 16

Vasoactive intestinal peptide

Question 17

What is found in the shell region of SCN?

Answer 17

Vasopressin

Question 18

Where does input coming from light go to?

Answer 18

Core region of the SCN

Question 19

What is the major input of SCN?

Answer 19

Light entrainment directed from ganglion cells (sensitive to light)
Inputs from serotonergic systems
Input from processing if intergeniculate nucleus

Question 20

What is the intergeniculate nucleus?

Answer 20

Nucleus associated in reflex behaviours of visual system

Question 21

Where does the shell region of SCN transmit the information to?

Answer 21

Brain

Question 22

Where does the ventral subparaventricular zone project to?

Answer 22

Dorsal medial nucleus of the hypothalamus

Question 23

What is dorsal medial nucleus involved in?

Answer 23

Circadian regulation
Particular temperature regulation
Through medial preoptic area

Question 24

What does output to dorsal-paraventriculsr nucleus of hypothalamus involve?

Answer 24

Sympathetic regulation of melatonin production

Question 25

What is sleep cycle driven by?

Answer 25

Inhibitory group of neurons in ventrolateral preoptic area

Question 26

What is melatonin production caused by,

Answer 26

Sympathetic nerve activity to the membrane pineal gland found above the midbrain

Question 27

How is melatonin secreted?

Answer 27

A short light burst

Question 28

What does melatonin supplement?

Answer 28

Suprachiasmatic neural output and reinforces them

Question 29

What does melatonin have an effect on?

Answer 29

Normal sleep pattern

Question 30

What is important for sleep?

Answer 30

Preoptic area

Question 31

What is necessary for survival deprivation?

Answer 31

``` Animal models Loss of weight Failure to regulate body temperature Infections Death ```

Question 32

Human studies

Answer 32

``` Cognitive and memory impairment Leads to mood swings Hallucinations Fatal familial insomnia condition REM sleep ( rapid eye movement sleep) ```

Question 33

What is stage 1/2 of sleep as seen on EEG?

Answer 33

Sleep spindle is seen | Organised activity/ bursting activity/wider and higher amplitude - lower frequency EEG patterns

Question 34

Stage 3/4 of sleep seen on EEG

Answer 34

Slow waves/delta waves High amplitude Slow wave EEG pattern

Question 35

When does rapid eye movement state of sleep Increase?

Answer 35

during night

Question 36

Slow wave sleep

Answer 36

Considered stages III and IV

Question 37

What are active during REM sleep?

Answer 37

EOG-electro-oculogram- muscles

Question 38

What is observed during REM sleep?

Answer 38

Large muscles show paralysis

Question 39

What dominates in slow wave sleep?

Answer 39

Parasympathetic activity

Question 40

What neurotransmitter is involved in sleep/waking cycle?

Answer 40

Serotonin | Noradrenaline

Question 41

Where are the ACH cells found?

Answer 41

Between junction of mesencephalon and pons

Question 42

What prompted the cortical arousal?

Answer 42

Reticular formation has key nuclei

Question 43

What are important for waking stage?

Answer 43

Brainstem Locus coeruleus and Raphe ACH projections

Question 44

What brain regions are important for sleep promoting?

Answer 44

Anterior hypothalamus Ventrolateral posterior Ventrolateral preoptic area

Question 45

What plays an important role in controlling the sleep wake transition?

Answer 45

Oregon neurons of the lateral hypothalamus

Question 46

What does Previn neurons promote?

Answer 46

Arousal and wakefulness

Question 47

What does autoimmune destruction of ore in neuron cause?

Answer 47

Narcolepsy

Question 48

What does circadian rhythm do?

Answer 48

Keep us awake

Question 49

What is caffeine?

Answer 49

Antagonist against adenosine receptor

Question 50

What did Borberly and Dawn ‘84 purpose?

Answer 50

Circadian process and sleep homeostasis are integrated

Question 51

What does sleep homeostatic process Increase with?

Answer 51

Length of time awake

Question 52

What are the two electrophysiological state of Thalamocortical neurons?

Answer 52

Bursting | Totally active