DSA 3: Hypothalamus and Limbic System

Question 1

How does the hypothalamus specifically regulate homeostasis?

Answer 1

Water and electrolyte balance
Food intake
Blood pressure
Circadian rhythm
Stress response
Body metabolism

Question 2

What is the anterior (rostral) border of the hypothalamus?

Answer 2

Optic Chiasm

Question 3

What is the posterior (caudal) border of the hypothalamus?

Answer 3

Midbrain (tegmentum/PAG)

Question 4

What does the hypothalamus continue into?

Answer 4

Infundibular stalk and posterior pituitary

Question 5

Are mammillary bodies found on the anterior or posterior part of the hypothalamus?

Answer 5

Posterior

Question 6

What is the tuber cinereum?

Answer 6

Small swelling between optic chiasm and mammillary bodies - composes part of the floor

Question 7

What is the median eminence?

Answer 7

Arises from tuber cinereum and eventually becomes infundibulum

Question 8

What are three longitudinal divisions of the hypothalamus?

Answer 8

Anterior region
Tuberal region
Posterior region

Question 9

What divides the medial and lateral zones of the hypothalamus?

Answer 9

Fornix

Question 10

What happens if the lateral zone of the hypothalamus is damaged?

Answer 10

Decrease in feeding behavior that can lead to weight loss

Question 11

What nuclei are found in the supraoptic region of the medial zone?

Answer 11

Supraoptic nucleus
Paraventricular nucleus
Suprachiasmatic nucleus
Anterior nucleus

Question 12

What does the supraoptic nucleus do?

Answer 12

Contain ADH

Question 13

What does the paraventricular nucleus do?

Answer 13

Contain oxytocin

Question 14

What happens if there are lesions to the supraoptic and paraventricular nucleus?

Answer 14

Diabetes Insipidus
Increase water intake
Increase urination

Question 15

What does the suprachiasmatic nucleus do?

Answer 15

Receives retinal input and involved in circadian rhythms

Indirectly controls melatonin secretion in pineal gland

Question 16

What does the anterior nucleus do?

Answer 16

Range of visceral/somatic functions including temperature regulation

Question 17

What does the medial mammillary nucleus do?

Answer 17

Receive afferents from hippocampus via fornix

Efferents to thalamus and brainstem

Question 18

What happens if there is a lesion to the medial mammillary nucleus?

Answer 18

Inability to process short-term events into long term memory

Question 19

What does the ventromedial nucleus do?

Answer 19

Satiety center (tells that body is full)

Question 20

What happens if there is a lesion to the ventromedial nucleus?

Answer 20

Excessive eating leading to abnormal weight gain

Question 21

What does the dorsomedial nucleus do?

Answer 21

Subserves functions of emotional behavior and can cause sham rage

Question 22

What happens if there is a lesion to the dorsomedial nucleus?

Answer 22

Decrease in aggression and feeding

Question 23

What does the anteromedial group of the Circle of Willis supply?

Answer 23

Pre-optic and supraoptic region
Septal nuclei
Rostral portions of lateral hypothalamic area

Question 24

What does the posteromedial group of the Circle of Willis supply?

Answer 24

Tuberal and mammillary region

Question 25

What is the role of the fornix?

Answer 25

Transmits information from hippocampus to hypothalamus

Question 26

What is the role of the medial forebrain bundle (MFB)?

Answer 26

Transmits information from septal nuclei, midbrain tegmentum, and hypothalamus itself to hypothalamus through lateral hypothalamic zone

Question 27

What is the role of the amygdalohypothalamic fibers?

Answer 27

Transmits information from septal nuclei, pre-optic area, and medial hypothalamic zone to hypothalamus

Question 28

What is the role of the mammillary fasciculus?

Answer 28

Transmits information from medial mammillary nucleus to anterior nucleus, playing a role in circuit of Papez

Question 29

What is the role of the hypothalamic fibers?

Answer 29

Transmits information from lateral pre-optic area to dorsomedial nucleus of the thalamus and amygdaloid nucleus

Question 30

What is the supraoptichypophyseal tract?

Answer 30

Composed of axons from supraoptic and paraventricular nucleus to the posterior pituitary to release oxytocin and

Question 31

What is the tuberoinfundibular tract?

Answer 31

Inputs from hypothalamic neurons to anterior pituitary

Question 32

What is the role of the limbic system?

Answer 32

Influence behavior, memory, and pain perception

Question 33

What structures compose the hippocampus?

Answer 33

Subiculum Entorhinal cortex Dentate Gyrus CA1, CA2, CA3, CA4

Question 34

What is the afferent pathway of the hippocampus?

Answer 34

Dentate gyrus --> CA3 --> CA1 --> subiculum

Question 35

What is the efferent pathway of the hippocampus?

Answer 35

Subiculum --> fornix

Question 36

What are the afferents of the cingulate gyrus?

Answer 36

From the thalamus and cortex

Question 37

What are the efferents of the cingulate gyrus?

Answer 37

To the entorhinal cortex of hippocampus

Question 38

What is the stria terminalis?

Answer 38

Outputs to hypothalamus and basal ganglia to permit motor behavioral responses from amygdala

Question 39

What is the ventral amygdalofugal pathway?

Answer 39

Efferent pathway: amygdala to various parts of the brain

Question 40

What is the Papez circuit?

Answer 40

Neural circuit for the control of emotional expression

Question 41

What is the function of the septal region?

Answer 41

Control rage of behavior

Question 42

What is the function of the ventral tegmental area?

Answer 42

Reward Motivation Role in addiction

Question 43

What happens if there is a bilateral lesion of the hippocampus?

Answer 43

Anterograde episodic memory (cannot learn new memory)

Question 44

What structures are damaged in Korsakoff's Syndrome?

Answer 44

Mammillary bodies Hippocampal complex Dorsomedial thalamic nucleus

Question 45

What happens with patients who have Korsakoff's Syndrome?

Answer 45

Impedes retention of newly acquired memory Short term memory doesn't become long term memory Will be confabulate (fragmented memories)

Question 46

What is phantosmia?

Answer 46

Distortion in a smell experience or the perception of a smell when no odor is present

Question 47

What is Kluver Bucy syndrome?

Answer 47

``` Bilateral temporal lobe lesions that abolish amygdaloid complex leading to: Visual agnosia Hyperorality Hypermetamorphosis Placidity Hyperphagia Hypersexuality ```