12a: Hypothalamus

Question 1

List the three zones of the hypothalamus, from medial to lateral.

Answer 1

1. Periventricular zone
2. Intermediate/medial zone
3. Lateral zone

Question 2

List the levels/regions of hypothalamus, from rostral to caudal.

Answer 2

1. Preoptic
2. Anterior/supraoptic
3. Tuberal
4. Posterior

Question 3

The periventricular zone of hypothalamus contains which nuclei?

Answer 3

1. Paraventricular (PVN)
2. Periventricular (PrVN)
3. Arcuate (Arc)

Question 4

Which hypothalamic nuclei extend the entire (AP/ML) length of hypothalamus EXCEPT for (X) zone/region?

Answer 4

AP;

PrVN (periventricular) and LHA (lateral hypothalamic area)

X = preoptic region

Question 5

The lateral zone of hypothalamus contains which nuclei?

Answer 5

1. SON (supraoptic)
2. LPN (lateral pre optic)
3. LHA (lateral hypothalamic area)

Question 6

Functions of hypothalamus are largely related to (X). It does this by way of:

Answer 6

X = homeostasis

1. ANS
2. Pituitary
3. Limbic system/cortex

Question 7

Hypothalamus controls species preserving behaviors by its connection with:

Answer 7

Limbic system/cortex

Question 8

Hypothalamus controls BP and body T by its connection with:

Answer 8

ANS

Question 9

Hypothalamus controls hormones by its connection with:

Answer 9

Pituitary gland

Question 10

Hypothalamus controls physiological arousal/stress by its connection with:

Answer 10

ANS

Question 11

Hypothalamus controls HR and respiration by its connection with:

Answer 11

ANS

Question 12

Hypothalamus controls drives and emotion by its connection with:

Answer 12

Limbic system/cortex

Question 13

Hypothalamus connects to the pituitary via the:

Answer 13

Infundibular stalk

Question 14

Seeing mammillary bodies is indicative of (anterior/medial/posterior) hypothalamus.

Answer 14

Posterior

Question 15

The preoptic region includes which hypothalamic nuclei?

Answer 15

MPN and LPN

Question 16

The anterior, aka (X), region of hypothalamus includes which hypothalamic nuclei?

Answer 16

X = supraoptic

1. SON
2. AN
3. PVN
4. SCN

Question 17

The tuberal region of hypothalamus includes which hypothalamic nuclei?

Answer 17

1. Arc

2. VM and DM

Question 18

The posterior region of hypothalamus includes which hypothalamic nuclei?

Answer 18

1. PN

2. MB

Question 19

(X) is the rostrally adjacent tissue of telencephalon that’s continuous with (Y) area of hypothalamus.

Answer 19

X = basal forebrain;
Y = preoptic

Question 20

The basal forebrain is interconnected with the (X) forebrain and is the source of (ascending/descending) (Y) afferents to (Z).

Answer 20

X = limbic;
Ascending;
Y = cholinergic;
Z = entire cerebral cortex

Question 21

In a general sense, stimulation of (X) regions of hypothalamus leads to parasympathetic effects. And stimulation of (Y) regions leads to sympathetic effects.

Answer 21

X = anterior and medial
Y = posterior and lateral

Question 22

Obesity has been shown to be a result of lesions to which part/nucleus of hypothalamus?

Answer 22

Ventromedial nucleus

Question 23

Starvation (due to aphagia) can result from lesions to which part/nucleus of hypothalamus?

Answer 23

Lateral hypothalamus

Question 24

In the forebrain, lesions of hypothalamus and (X) lead to serious disturbances of circadian rhythm. These depend upon internal generators in which hypothalamic nucleus?

Answer 24

X = nothing else (only hypothalamus)

SCN

Question 25

Without (X) input, circadian rhythms continue on periodicity that's (Y) hours long.

Answer 25

``` X = retinal (light) Y = slightly longer than 24 ```

Question 26

SCN nucleus in hypothalamus has (Y) receptors that responds to (Y) produced by (Z).

Answer 26

``` Y = melatonin; Z = pineal gland ```

Question 27

The (X) gland receives "visual" input (directly/indirectly) via its innervation from (Y).

Answer 27

X = pineal; Indirectly; Y = superior cervical ganglion (sympathetic innervation)

Question 28

T/F: Damage to superior cervical ganglion disrupts melatonin secretion by pineal gland.

Answer 28

True

Question 29

Hypothalamic connections that support all its functions can be divided into which 5 main categories?

Answer 29

1. Endocrine Control 2. ANS control 3. Species-preserving behavior 4. Limbic/cortical connections 5. Circadian rhythm control

Question 30

Feedback control of hypothalamic endocrine function is largely via receptors responsive to (X).

Answer 30

X = physiological state (body T, osmolarity, glucose, etc.) and hormones

Question 31

List the tract(s) that allow hypothalamic control of endocrine function.

Answer 31

1. Supraoptico-hypophyseal tract | 2. Tuberoinfundibular tract

Question 32

The Supraoptico-hypophyseal tract is formed by axons of neurons in (X) nuclei of hypothalamus. They travel down (Y) to get to (Z).

Answer 32

``` X = PVN and SON Y = pituitary stalk Z = posterior pituitary ```

Question 33

Which (hormones/NTs) are transported down the Supraoptico-hypophyseal tract? What's their effect/fate?

Answer 33

Hormones; ADH and oxytocin; Released directly into capillaries in posterior pituitary

Question 34

The Tuberoinfundibular tract is a series of (short/long) axons from which hypothalamic nuclei? They produce (X).

Answer 34

Short; Arcuate nuclei; X = releasing and inhibiting factors

Question 35

In (Supraoptico-hypophyseal/Tuberoinfundibular) tract, the releasing and inhibiting factors, released by (X) into (Y), then drain into (Z).

Answer 35

Tuberoinfundibular; X = neurons of Arcuate nuclei Y = capillaries of median eminence; Z = hypophyseal portal vein

Question 36

The dorsal longitudinal fasciculus is an (efferent/afferent) path connecting (X) and (Y).

Answer 36

Both (bi-directional); X = hypothalamus Y = sympathetic and parasympathetic structures

Question 37

Afferent input via DLF distrubites to (X) hypothalamic nuclei via ascending fibers from (Y) structures.

Answer 37

``` X = PrVN and PN Y = parabrachial nucleus ```

Question 38

The parabrachial nucleus is relaying information about (X) sensations to hypothalamic nuclei via (Y) tract.

Answer 38

``` X = pain (protopathic), taste, visceral sensation Y = DLF ```

Question 39

Efferent output via DLF arises from (X) nuclei.

Answer 39

X = PVN, SON, PrVN, LHA

Question 40

Efferent fibers traveling via DLF project to:

Answer 40

1. PAG 2. VTA 3. Medullary autonomic centers 4. Brainstem parasympathetic nuclei 5. Thoracolumbar and Lumbosacral preganglionics

Question 41

Supraoptico-hypophyseal tract consists of (magno/parvo)-cellular neurons.

Answer 41

Magnocellular

Question 42

Tuberoinfundibular tract consists of (magno/parvo)-cellular neurons.

Answer 42

Parvocellular

Question 43

Reward is processed as (high/low) levels of which NT?

Answer 43

High; | DA

Question 44

In androgen insensitivity syndrome, genetic defect in (X) results in genetic (M/F) developing fully as (M/F).

Answer 44

X = androgen receptors; | M; F

Question 45

Patient with androgen insensitivity syndrom has (testes/ovaries), circulating (testosterone/androgen), and (vagina/penis).

Answer 45

Testes, testosterone, but vagina (since testosterone receptors are absent)

Question 46

List the effects of pituitary tumor.

Answer 46

1. Visual problems 2. Arrested growth (children) 3. Sexual dysfunction (adults) 4. Mood/feeding changes