3. Hypothalamus & Limbic System DSA

Question 1

Where is the medial preoptic nucleus? What does it do?

Answer 1

Preoptic area of hypothalamus

Contains neurons that make GnRH

Question 2

What structure does the periventricular zone of the hypothalamus surround?

Answer 2

3rd ventricle

Question 3

What are the regions of the medial zone of the hypothalamus?

Answer 3

Supraoptic region

Tuberal region

Mammillary region

Question 4

What hypothalamic structure forms the anterior boundary of the 3rd ventricle?

Answer 4

Lamina terminalis

Question 5

Where is the medial forebrain bundle located? What does it connect?

Answer 5

Lateral zone of the hypothalamus

Interconnects hypothalamus from the rostral areas (such as septal nuclei) to the caudal areas (Reticular formation)

Question 6

Stimulation of what hypothalamic nucleus promotes feeding behavior?

Answer 6

Lateral hypothalamic nucleus

Question 7

Lesion of what hypothalamic nucleus causes increased feeding?

Answer 7

Ventromedial nucleus

Question 8

Where is the dorsomedial nucleus of the thalamus located? What is its function?

Answer 8

Tuberal region

Regulates emotional behavior (Stimulation produces aggressive behavior)

Question 9

What is the primary function of the anterior nucleus of the hypothalamus?

Answer 9

Maintenance of body temperature

Question 10

What nuclei are contained within the supraoptic region of the hypothalamus?

Answer 10

Supraoptic/paraventricular nucleus

Suprachiasmatic nucleus

Anterior nucleus

Question 11

What nuclei are contained within the tuberal region of the hypothalamus?

Answer 11

Ventromedial nucleus

Dorsomedial nucleus

Arcuate nucleus

Question 12

What structure transmits hormones from the arcuate nucleus of the hypothalamus to the anterior pituitary?

Answer 12

Tuberoinfundibular tract and hypophysial portal system

Question 13

What hypothalamic nucleus represents the primary termination point for axons of the postcommissural fornix?

Answer 13

Medial mammillary nucleus

Question 14

Where do axons of the postcommissural fornix arise from?

Answer 14

Subiculum

Question 15

What does the mammillothalamic tract transmit?

Answer 15

Axons from medial mammillary nucleus to the anterior nucleus of the dorsal thalamus

Question 16

What does the mammillary peduncle transmit?

Answer 16

Information from the midbrain reticular formation to the intermediate and lateral mammillary nuclei

Question 17

Inability to process short-term memory iinto long-term memory may be a sign of a lesion where?

Answer 17

Mammillary body

Question 18

What does the supraoptic nucleus transmit to the posterior pituitary?

Answer 18

Oxytocin and ADH

Question 19

What structure does the posterior hypothalamic nucleus merge with?

Answer 19

Periaqueductal gray matter

Question 20

What is the blood supply to the preoptic area, supraoptic region, septal nuclei, and rostral portions of the lateral hypothalamic area?

Answer 20

Anteriomedial group branching from the A1 segment (ACA)

Question 21

What is the blood supply to the tuberal and mammillary regions of the hypothalamus?

Answer 21

Rostral portion of P1 => Tuberal

Caudal portion of P1 => Mammillary

Question 22

What structure provides the largest single afferent input to the hypothalamus?

Answer 22

Fornix

Question 23

Where does the stria terminalis originate and where does it terminate?

Answer 23

Origin: Corticomedial portion of amygdala

Terminate: Septal nuclei

Question 24

What are the hypothalamic efferent structures?

Answer 24

Fornix

Medial forebrain bundle

Amygdalohypothalamic fibers

Question 25

Where do the axons of the ventral amygdalofugal pathway terminate?

Answer 25

Lateral hypothalamic zone Septal and preoptic nuclei

Question 26

What does the mammillary fasciculus originate as and where does it go?

Answer 26

Origin: Medial mammillary nucleus =\> mammillothalamic and mammillotegmental tracts =\> anterior nucleus of the thalamus

Question 27

What is the pathway of the hypothalamothalamic fibers?

Answer 27

Lateral preoptic area =\> project to dorsomedial nucleus (thalamus) and amygdaloid nucleus via stria terminalis and ventral amygdalofugal pathway

Question 28

What hypothalamic fibers terminate directly in the ANS?

Answer 28

Hypothalamospinal and hypothalamomedullary fibers - arise from PVN Hypothalamomedullary fibers - terminate in solitary nucleus, dorsal vagal motor nucleus, nucleus ambiguus Hypothalamospinal fibers - terminate in intermediolateral cell column

Question 29

What structure do the indirect fibers from the hypothalamus target?

Answer 29

Periaqueductal Gray Matter

Question 30

What tract transports oxytocin and ADH to the posterior pituitary?

Answer 30

Supraopticohypophysial tract

Question 31

What parts of the brainstem does the tuberoinfundibular tract convey its hormones?

Answer 31

Median eminence Infundibulum

Question 32

What thalamic nucleus is composed of parvicellular, magnocellular, and paralaminar parts?

Answer 32

Medial Thalamic Nuclei

Question 33

What lateral thalamic nuclei receive and send nociceptive cutaneous input transmitted over somatosensory pathways?

Answer 33

Posterior nuclear complex

Question 34

A stroke involving what thalamic artery may result in total/dissociated sensory loss? May result in what syndrome?

Answer 34

Thalamogeniculate A. Dejerine-Roussy Syndrome

Question 35

What comprises the hippocampal formation?

Answer 35

Subiculum Hippocampus Dentate gyrus

Question 36

What is the major input to the hippocampus?

Answer 36

Cells of Entorhinal cortex via peroforant pathway

Question 37

What is the path of the Circuit of Papez?

Answer 37

1. Medial mammillary nucleus =\> mammillothalamic tract =\> anterior nucleus of thalamus 2. Thalamus =\> Thalamocortical fibers =\> Cingulate gyrus 3. Cingulate gyrus =\> Entorhinal cortex, subiculum, and hippocampus 4. Subiculum =\> Fornix =\> Mammillary body

Question 38

What are the amygdaloid efferents?

Answer 38

Stria terminalis Ventral amygdalofugal pathway Stria medullaris thalami

Question 39

What role do the nucleus accumbens and ventral tegmental area play in the limbic system?

Answer 39

Behaviors related to addiction and chronic pain

Question 40

What happens if there are bilateral lesions in the hippocampi?

Answer 40

Amnesia - deficit in anterograde episodic memory (cannot learn new material) but procedural and working memory is spared

Question 41

In Korsakoff's syndrome, what structures undergo degeneration? What function does this impede?

Answer 41

Mammillary bodies, hippocampal complex, dorsomedial thalamic nucleus Cannot commit short term memory to long term memory

Question 42

A patient is a chronic alcoholic. Upon exam, he appears to be unable to understand words on a page. He describes events that have not happened. If left untreated, what disorder may this patient be at risk for?

Answer 42

Korsakoff's syndrome

Question 43

Where is the lesion if a patient is experiencing phantosmia?

Answer 43

Anterior/Medial Temporal lobe, hippocampus, amygdala, or medial dorsal thalamic nuclei

Question 44

What has been destroyed in a patient with Kluver-Bucy syndrome?

Answer 44

Amygdaloid complex

Question 45

What behavior changes might you see in a patient with Kluver Bucy Syndrome?

Answer 45

Visual agnosia Hyperorality - examines objects w mouth Hypermetamorphosis - Overreaction to visual stimuli Placidity - No fear or anger even when appropriate Hyperphagia - eating lots Hypersexuality

Question 46

What CN is involved in uncal herniation?

Answer 46

CN III (Dilated pupil, double vision ipsilateral to hernia)

Question 47

If an uncal herniation is compressing the brainstem and weakness is seen in the right extremities, where is the lesion?

Answer 47

Left CST