23. CIRCADIAN RHYTHM, SLEEP/WAKE CYCLE; NEUROANATOMY OF RESTING STATE AND ACTIVATION Flashcards

1
Q

What is The principle of the control of circadian (daily) rhythms?

A

„Glomerular filtration rate and tubular reabsorption/secretion peak during the active phase and decline during the inactive phase.”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is The pacemaker of the human body?

A

Suprachiasmatic nucleus (SCN)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Name of this area

A

Anterior hypothalamic region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Identify this nucleus

A

Suprachiasmatic nucleus (SCN)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Neuronal inputs to the hypothalamus
-> Identify

A

Retino-hypo-thalamic fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Origin of the retino-hypothalamo pathway

A

Photoreception is not
confined to rods (red) and cones (green) but is also accomplished by a subset of intrinsically photosensitive retinal ganglion cells (yellow), the so-called circadian photoreceptors, that employ melanopsin as a photopigment and give rise
to the retinohypothalamic tract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Name Neuronal connections of the suprachiasmatic nucleus (SCN) - 2

A

GnRH: gonadotropin releasing hormone cells
MPOA: medial preoptic nucleus
CRH: corticotropin releasing hormone cells
dPVN: dorsal subdivision of the paraventrocular
hypothalamic nucleus (PVN)
sPVN: subventricular subdivision of the PVN
DMH: dorsomedial hypothalamic nucleus
PVT: paraventricular thalamic nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Name Neuronal connections of the suprachiasmatic nucleus (SCN) (part 1)

A
  1. Glu: Glutamate
  2. GABA: Gamma aminobutyric acid
  3. VIP: Vasoactive intestinal polypeptide
  4. IGL: Intergeniculate leaf nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Circadian regulation of cortisol secretion from the adrenal gland (Adr)
-> Name the structures involved

A

CRH: corticotropin releasing hormone
ACTH: adrenocorticotropin Adr: adrenal gland
IML: intermediolateral cell column of the spinal cord (sympathetic premotor neurons)
PVN: paraventricular hypothalamic nucleus
SCN: suprachiasmatic nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Make a schematic diagram of Circadian regulation of cortisol secretion from the adrenal gland (Adr)

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

One output of SCN is the pineal gland (PIN), from which ____ provides a negative feedback

A

melatonin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

One output of SCN is the pineal gland (PIN), from which melatonin provides a negative feedback
-> identify

A
  1. RET: retina
  2. RHT: retino-hypothalamic tract
  3. MEL: melatonin
  4. NA: noradrenalin
  5. IML: intermediolateral cell column of the spinal cord (sympathetic premotor neurons)
  6. PVH: paraventricular hypothalamic nucleus
  7. GCS: superior cervical ganglion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Definition / characteristics of sleep

A
  • Decreased motor activity
  • Stereotyped posture
  • Refreshing, fatigue-reducing effect
  • Daily rhythmicity
  • Rebound effect
  • Changes in brain electrical potentials
  • Increase in stimulus threshold
  • Relatively easy to wake up
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Phenomenologic explanation of motivation to sleep
-> S, C, S-C??

A

S: Homeostatic drive to sleep (e.g. a sleep substance)
C: Circadian drive to be awake
S-C shows how sleepy we feel.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Phenomenologic explanation of motivation to sleep
-> What does the schematics explains?

A
  1. Daily rhythm of sleep;
  2. Effects of sleep deprivation: - Why we are less sleepy in the morning than at night; - Why we sleep more the following night (rebound effect) but less than 2 times more.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Sleep stages based on electroencephalogram (EEG)

A

REM sleep: rapid eye movement of paradoxical sleep
Stage 4: slow wave sleep (SWS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name of this system

A

Ascending reticular activating system

18
Q

State-dependent modes of thalamic relay cells
-> Name the nucleus and cell

A
  1. Reticular nucleus
  2. Thalamic relay cell
19
Q

List Cell types and connections of the thalamic reticular nucleus

A

GABA-erg neurons in the thalamus
Cortical pyramidal cell
Reticular cell
Thalamocortical cell

20
Q

Cell types and connections of the thalamic reticular nucleus
-> Identify

A
  1. Cortical pyramidal cell
  2. Reticular cell
  3. Thalamocortical cell
21
Q

Neuronal mechanisms of active sleep control
-> What are some methods of identifying brain areas involved in sleep regulation

A
  • Correlation of neuronal activity with sleep and its phases
  • Investigating how sleep cycle is affected by chemo- and optogenetic manipulation of neuronal activity, as well as brain lesions and pathway transections
  • Neurochemical investigation of pathway systems involved in sleep regulation
  • Influencing sleep with pharmacons
  • Examination of the sleep cycle in transgenic animals
  • Study of sleep disorders
22
Q

What is VLPO?

A

VLPO: ventrolateral preoptic nucleus

23
Q

Antero-posterior regions of the hypothalamus
-> Identify these regions

A
24
Q

Ascending monoaminerg reticular activating systems
-> Name 4 systems

A
25
Q

What is the characteristics of Ascending monoaminerg reticular activating pathways?

A

reach the cerebral cortex without relay in the thalamus

26
Q

Which part of the brain promote waking?

A

The hypocretin / orexin neurons in the lateral hypothalamic area

27
Q

What can disappearence of orexin neurons cause?

A

It causes narcolepsy, a relatively frequent disease characterized by sleepiness, cataplexy, and hypnagog hallucinations.

28
Q

́Flip-flop ́ model of sleep regulation

A
29
Q

Rapid eye movement (REM) sleep stage

A
  • Low-amplitude, mixed- frequency EEG
  • Ponto-geniculo-occipital (PGO) waves
  • Easier to wake up
  • Increase in cerebral metabolism and temperature
  • Heart rate, blood pressure and breathing rate increase compared to slow wave sleep
  • Weakening of homeostatic regulation
  • Trunk muscle atony
  • Pupil constricts (miosis)
30
Q

What does Resting state mean?

A

A cognitive state in which the subject is alert but at rest, and does not participate in any specific cognitive or behavioral task.

31
Q

Classification of cerebral cortical brain regions

A
32
Q

There are 3 groups of brain regions, called 3 functional connectivity networks, whose activity changes similarly in the resting state
-> Name of these 3 networks?

A
  1. Default Mode Network (DMN)
  2. Central Executive Network (CEN)
  3. Salience Network (SN)
33
Q

Resting-state networks
-> What is the role of Default Mode Network (DMN)?

A

„Task-negative” network because its activity is actually reduced during behaviour. In turn, the activity of the network increases during internal mental activity, e.g. self examination but not when specific tasks are addressed

34
Q

Resting-state networks
-> Which structures involve in Default Mode Network (DMN)?

A

VMPFC and DMPFC (MDPC) ventromedial and dorsomedial prefrontal cortex

ACC, MCC and PCC: anterior, middle and posterior cingular cortex

PC: precuneus; PHG (SPL): parahippocampal gyrus

Hi: hippocampus

LTC: lateral temporal cortex (not visible)

35
Q

Resting-state networks
-> What is the role of Central Executive Network (CEN)?

A

Increased activity during any cognitive or affective process, especially during goal-oriented behavior

36
Q

What is the role of Salience Network (SN)?

A

Increased activity during cognitive or affective processes, especially during the perception, integration and highlighting of relevant autonomic and emotional information

37
Q

What are Sub-networks of the Default Mode Network?

A

Diffusion tensor imaging verified pathways connecting the elements of the DMN. It also contributed to define a dorsal DMN subnetwork (prefrontal, cingular cortices and precuneus) and a ventral DMN subnetwork: from precuneus to hippocampus.

38
Q

The role of Precuneus

A

Precuneus is responsible for visual-spatial imaging, memory recall, meditation, self- control, self-awareness, point of view, individual thoughts, planning, forming a vision of the future.
=> In addition to other parts of the DMN, it also connects to the supplementary and premotor cortex to initiate the motor executive program.

39
Q

Resting-state networks
-> Which structures involving in Central Executive Network (CEN)?

A

DLPFC and DMPFC: dorsolateral and dorsomedial prefrontal cortex; PPC: posterior parietal cortex; FEF: frontal eye field

40
Q

Resting-state networks
-> Which structures involving in Salience Network (SN)?

A

IC: insular cortex; dACC: dorsal anterior cingulate cortex; TP: temporal pole; Amy: amygdala

41
Q

Comparison of resting-state networks
-> Which slide belong to which networks?

A