3. DSA: Hypothalamic and Limbic Systems Flashcards

1
Q

Small anatomical region of diencephalon that integrates information from forebrain, brainstem, and SC

A

Hypothalamus

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

What is the primary role of the hypothalamus?

A

Maintenance of homeostasis (water and electrolyte balance, food intake, temperature, blood pressure, circadian rhythm, stress responses, body metabolism)

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

Name the boundaries of the hypothalamus.

A

Optic chiasma (anterior) and tegmentum/PAG of midbrain (posterior)

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

What forms the floor and ventral walls of 3rd ventricle?

A

Hypothalamus

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

What is continuous through the infundibular stalk with the posterior pituitary?

A

Hypothalamus

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

What forms the posterior part of the hypothalamus?

A

Mammillary bodies

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

What are adjacent to the cerebral peduncles?

A

Mammillary bodies

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

Where is the tuber cinerum?

A

Small swelling between the mammillary bodies and optic chiasm/tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Where is the median eminence?

A

Arises from the tuber cinerum and narrows into the infundibulum (attaches to the pituitary gland)

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

What are the longitudinal divisions of the hypothalamic nuclei?

A

Anterior region, tuberal region, and posterior (mammillary) region

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

Where is the anterior region?

A

Superior to the optic chiasm extending anteriorly to the lamina terminalis

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

Where is the tuberal region?

A

Superior to and including the tuber cinerum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is the mammillary/posterior region?

A

Superior to and including the mammillary bodies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where is the periventricular zone?

A

Periaqueductal gray (midbrain) through in the wall of the 3rd ventricle

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

What divides the hypothalamus into the medial and lateral zones?

A

Fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Where is the median forebrain bundle (MFB) located?

A

Lateral zone of the hypothalamic nuclei

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

Damage to the lateral zone of the hypothalamic nuclei results in __.

A

Decrease in feeding behavior

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What nucleus contains oxytocin and ADH?

A

paraventricular (OT)/Supraoptic(ADH) nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where does the supraoptic/paraventricular nucleus lead into?

A

Posterior pituitary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lesion in the SO/PVN results in __.

A

Diabetes insipidus (DI), increased H2O intake, and increased urination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What nucleus receives retinal input and is involved in circadian rhythms?

A

Suprachiasmatic nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Lesion in the SCN results in __.

A

Modification or elimination of circadian rhythms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the anterior nucleus responsible for?

A

Range of visceral/somatic functions and temperature regulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Where do afferents leading to the medial mammillary nucleus come from?

A

Hippocampus (via fornix)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Where do efferents coming from the medial mammillary nucleus go?

A

Thalamus and brainstem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Lesion in the medial mammillary nucleus results in __.

A

Inability to process short-term events into long-term memory

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is considered the “satiety center”?

A

Ventromedial nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Lesion in the ventromedial nucleus results in __.

A

Excessive eating and abnormal weight gain

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What nucleus subserves functions of emotional behavior?

A

Dorsomedial nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Stimulation of dorsomedial nucleus causes __.

A

Sham rage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Destruction of dorsomedial nucleus results in __.

A

Decreased aggression and feeding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Name the blood supply of the anteromedial group of the hypothalamus.

A

Branches from the anterior communicating and anterior cerebral arteries (A1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Name the blood supply of the posteromedial group of the hypothalamus.

A

Perforating arteries from the posterior communicating artery and posterior cerebral artery (P1)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Name the major afferent routes of the hypothalamus.

A

Fornix, medial forebrain bundle (MFB), and amygdalohypothalamic fibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Where does the fornix arise from?

A

Subiculum and hippocampus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the largest single input to the hypothalamus?

A

Fornix

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What structures does the MFB interconnect?

A

Spectal nuclei, hypothalamus, and midbrain tegmentum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Where does the MFB course through?

A

Lateral hypothalamic zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What pathways are composed of amygdalohypothalamic fibers?

A

Stria terminalis and ventral amygdalofugal pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What do the stria terminalis and ventral amygdalofugal pathways target?

A

Septal nuclei, pre-optic area, and medial hypothalamic zone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Name the efferent hypothalamic pathways.

A

Mammillary fasciculus and hypothalamic fibers

42
Q

Where does the mammillary fasciculus orginate from?

A

Medial mammillary nucleus

43
Q

What does the mammillary fasciculus bifurcate into?

A

Mammillothalamic and mammillotegmental tracts

44
Q

Where does the mammillary fasciculus project to?

A

Anterior nucleus (thalamus): an important part of the circuit of Papez

45
Q

Where does the hypothalamothalamic fibers originate from?

A

Lateral preoptic area

46
Q

Where do the hypothalamothalamic fibers project to?

A

Dorsomedial nucleus (thalamus) and amygdaloid nucleus

47
Q

How do the hypothalamothalamic fibers get to the dorsomedial nucleus and amygdaloid nucleus?

A

Via the stria terminalis and ventral amygdalofugal pathways

48
Q

All the vital functions of the hypothalamus are controlled through reflexes mediated by __.

A

Autonomic or endocrine systems

49
Q

Name the direct links to the ANS from the hypothalamus.

A

Hypothalamomedullary fibers and hypothalamospinal fibers

50
Q

Where do the hypothalamomedullary fibers go?

A

Solitary nucleus, dorsal vagal motor nucleus, and nucleus ambiguus

51
Q

Where do the hypothalamospinal fibers go?

A

Intermediolateral cell column (GVE pre-ganglionics)

52
Q

Lesions in the __ disrupt the hypothalamomedullary and hypothalamospinal fibers.

A

Anterolateral medulla

53
Q

The hypothalamomedullary fibers and hypothalamospinal fibers provide sympathetic outflow to the __.

A

Face and head (Horner’s syndrome) or body

54
Q

Name the indirect links to the ANS.

A

Posterior longitudinal fasciculus and mammillotegmental tract

55
Q

What do the posterior longitudinal fasciculus and mammillotegmental tract target?

A

PAG (periaqueductal gray)

56
Q

What does the PAG target?

A

Other visceral areas of the brainstem (solitary and dorsal motor vagal nuclei)

57
Q

Indirect link to the ANS short tracts influence __.

A

Autonomic nuclei in the brainstem

58
Q

Where are oxytocin and ADH stored?

A

Herring bodies

59
Q

Where are the oxytocin and ADH released into?

A

Capillary plexus of posterior pituitary

60
Q

Cellbodies of neuronsof the tuberoinfundibular tract are located in __.

A

Periventricular zone, PVN, and others

61
Q

The tuberoinfundibular tract convert releasing hormones to __.

A

Median eminence and infundibulum

62
Q

What receives direct input from the retina to mediate circadian rhythms?

A

Suprachiasmatic nucleus

63
Q

What are hormonal fluctuates secondary to light-dark cycles?

A

Circadian rhythms

64
Q

What does SCN activity do?

A

Opposes drive for sleep (essential for timing of rest vs. activity)

65
Q

How do cells maintain 24-hour periodicity?

A

Via transcription/translation control of circadian genes which indirectly control melatonin secretion (pineal gland)

66
Q

Describe cycle of melatonin levels.

A

Increases just prior to normal sleep output

67
Q

What is the internal indicator of circadian time and feedbacks to SCN?

A

Control of melatonin secretion

68
Q

What are the parts of the limbic system?

A
  1. Subcallosal area
  2. cingulate gyrus
  3. parahippocampal gyrus
  4. uncus
  5. hippocampal formation
  6. subcortical nuclei
69
Q

Connections of the limbic system influence __(1-3)__.

A

(1) behavior, (2) memory, (3) pain perception

70
Q

What was the first description of an anatomicophysiologic mechanism for emotion?

A

Papez circuit

71
Q

What is an important gyrus in the Papez circuit?

A

Cingulate gyrus

72
Q

What is the function of the hippocampal formation?

A

Learning and memory

73
Q

What does the hippocampal formation include?

A

Hippocampus, subiculum, entorhinal cortex, and dentate gyrus

74
Q

What is the subiculum?

A

Transitional area between the hippocampus and entorhinal cortex

75
Q

What are the parts of the subiculum?

A

CA1 - CA4

76
Q

What is the afferent pathway of the hippocampal formation?

A

Dentate gyrus —> CA3 —> CA1 —> subiculum

77
Q

What is the efferent pathway of the hippocampal formation?

A

Subiculum —> fornix

78
Q

Where does the efferent pathway of the hippocampal formation terminate?

A

Medial mammillary nucleus, ventromedial nucleus, and anterior nucleus of dorsal thalamus

79
Q

Where are the other projections of the efferent pathway of the hippocampal formation?

A

Septal nuclei, frontal cortex, preoptic and anterior nuclei (hypothalamus), and nucleus accumbens

80
Q

Where is the cingulate gyrus located?

A

Medial aspect of cerebral cortex

81
Q

Where is the cingulate gyrus?

A

Lies immediately above the corpus callosum as continuation of cingulate sulcus

82
Q

Where do afferents from the cingulate gyrus come from?

A

Thalamus and cortex

83
Q

Where does the cingulate gyrus project to?

A

Entorhinal cortex via the cingulum

84
Q

What is the function of the amygdala?

A

Motivational and emotional connotations of experience

85
Q

Where is the amygdala located?

A

Deep and medially within temporal lobe

86
Q

Where do afferents of the amygdala come from?

A

Inferior temporal association cortex, thalamus, septum and olfactory tract, and brainstem

87
Q

What are the efferent projections to the amygdala?

A

Stria terminalis and ventral amygdalofugal pathway

88
Q

Where does the stria terminalis send outputs?

A

To the hypothalamus and basal ganglia to permit motor behavioral responses

89
Q

Where does the ventral amygdalofugal pathway send efferents?

A

Hypothalamus and septal nuclei and frontal and prefrontal, cingulate, insular cortices; brainstem to terminate in visceral nuclei and Raphe nuclei

90
Q

What is the function of the Papez circuit?

A

Modulating feelings (fear, anxiety, sadness, happiness)

91
Q

What does the Papez circuit consist of?

A

Cingulate gyrus —> hippocampal formation (subiculum and entorhinal cortex) / Hippocampus —> fornix —> medial mammillary nuclei —> anterior nucleus (thalamus via mammillothalamic tract) / anterior nucleus —> cingulate gyrus

92
Q

What is the small area just rostral to the anterior commissure?

A

Septal region

93
Q

What is the septal region through to control?

A

Rage behavior

94
Q

What is the diffuse group of dopaminergic fibers that courses rostrocaudally through the lateral hypothalamic area?

A

Medial forebrain bundle (MFB)

95
Q

What is the major conduit for septal nuclei and hypothalamus to communicate with the brainstem?

A

Medial forebrain bundle (MFB)

96
Q

Where is the nucleus accumbens?

A

Located in rostral and ventral forebrain where head of caudate nucleus and putamen are continuous

97
Q

From what structures does the nucleus accumbens receive inputs from?

A

Amygdala and hippocampus

98
Q

What does the nucleus accumbens play an important role in?

A

Behavior related to addiction and chronic pain

99
Q

What are the efferents of the nucleus accumbens?

A

Hypothalamus, brainstem, and globus pallidus

100
Q

Where is the ventral tegmental area?

A

Located medial to the substantia nigra

101
Q

What connections do the ventral tegmental area form?

A

With ventral striatum, amygdala, and other limbic structures

102
Q

What do efferents from ventral tegmental area to nucleus accumbens play an important role in?

A

Reward and motivation; may contribute to addiction