L21 and 22 - A

Question 1

The Limbic System is a border that separates which two structures?

Answer 1

Neocortex and Diencephalon

Question 2

Which seven structures belong to the Limbic System?

Answer 2

1. Hippocampal formation
2. Amygdala
3. Septal Nuclei
4. Cingulate Cortex
5. Entorhinal Cortex
6. Perirhinal Cortex
7. Parahippocampal Cortex

Question 3

True or False: The hippocampus is also known as the cornu ammonis (Ammon’s Horn)

Answer 3

True

Question 4

Which three components make up the Hippocampal Formation–which is a curved and re-curved sheet of cortex folded into medial surface of temporal lobe?

Answer 4

1. Hippocampus proper
2. Dentate Gyrus
3. Subiculum

Question 5

Which two structures form two interlocking “C’s”
A. Hippocampus proper
B. Dentate Gyrus
C. Subiculum

Answer 5

A. Hippocampus proper
B. Dentate Gyrus

Question 6

The hippocampus (and dentate gyrus) is actually a cortex, but it is a __ layered cortex as opposed to the __ layered cortex as in the neocortex

Answer 6

3; 6

Question 7

Because of the small number of layers and their location between the neocortex and diencephalon, these cortices have been called ____

Answer 7

paleocortex

Question 8

True or False: The hippocampus and the dentate gyrus, like the neocortex, have both a DEEP and SUPERFICIAL “molecular” layer

Answer 8

True

• note: molecular layer (inside) and polymorphic layer (outside)

Question 9

What is the middle layer of the hippocampus proper known as?

What is the middle layer of the dentate gyrus known as?

Answer 9

pyramidal cell layer

granular layer

Question 10

Inner layer of hippo - ________
Middle layer -________
Outer later - __________

Answer 10

Inner = molecular

Middle = pyramidal (hippo) / granule (dentate gyrus)

Outer = polymorphic

Question 11

True or False: The molecular layer of the hippocampus proper faces the dentate gyrus

Answer 11

True

Question 12

____: Area of the hippocampus proper that is capped by the dentate gyrus
A. CA3
B. CA2
C. BCB1
D. Alveus

Answer 12

A. CA3

Question 13

_____: Polymorphic layer of the hippocampus; it is equivalent to the white matter of the neocortex
A. CA3
B. CA2
C. BCB1
D. Alveus

Answer 13

D. Alveus

Question 14

True or False: The subiculum is the transition layer from the hippocampus to the parahippocampal gyrus (also - it changes from 3 to 6 layers)

Answer 14

True

Question 15

A major flow of information through the hippocampus comes from the….
A. PFC
B. Entorhinal Cortex
C. Primary Somatosensory Cortex

Answer 15

B. Entorhinal Cortex

Question 16

True or False: Neural activity can modify synaptic strength in certain parts of hippocampus – modified synaptic strength may be storage mechanism for memory

Answer 16

True

Question 17

True or False: Large, bilateral lesions of the hippocampus will affect memory of remote events and general intelligence; however, the person will be able to learn new facts and skills

Answer 17

False - large, bilateral lesions of the hippocampus will NOT affect memory of remote events and general intelligence; however, the person CANNOT learn new facts and skills

Question 18

Why do patient’s with Korsakoff Syndrome have a hard time forming new memories?

Answer 18

Mammillary bodies are destroyed

Question 19

What is the major pathway INTO and OUT of hippocampus?
A. PFC
B. Entorhinal Cortex
C. Primary Somatosensory Cortex
D. Fornix

Answer 19

D. Fornix

Question 20

True or False: The fornix starts as the alveus, communicates bidirectionally, and has efferent/afferent fibers

Answer 20

True

Question 21

____: White matter of the hippocampus, which consists of myelinated afferents/efferents

Answer 21

Alveus

Question 22

Answer 22

Question 23

Which two structures come together to form the hippocampal commissure?

Answer 23

Crura

Question 24

The fornix continues to an arc to the ___ ___

Answer 24

anterior commisure

Question 25

______: An important landmark, since this is where the fornix splints into three columns, going to different structures A. Crura B. Fornix C. Anterior Commisure

Answer 25

C. Anterior Commisure

Question 26

The split just before the anterior commisure is called the ______ while the split after the anterior commisure is called the ______

Answer 26

precommisual fornix; postcommisual fornix

Question 27

Which two places does the postcommisural fornix branch lead to?

Answer 27

1. Mammillary bodies (hypothalamus) 2. Anterior nuclei (thalamus)

Question 28

What are the two major pathways by which the hippocampi communicate with one another?

Answer 28

1) Hippocampal commissure 2) Anterior commisure to c/l hippocampus

Question 29

Which three structures does the precommissural fornix go to?

Answer 29

1 - Septal nuclei 2 - Ventral striatum 3 - Cingulate cortex

Question 30

_____: Integrative center for emotions, emotional behavior, and motivation

Answer 30

Amygdala

Question 31

True or False: Both the hippocampus and amygdala have major pathways that communicate bilaterally and contain both efferent/afferent fibers

Answer 31

True

Question 32

True or False: The amygdala receives inputs from all senses, as well as visceral inputs

Answer 32

True

Question 33

Which four structures provide visceral inputs to the amygdala?

Answer 33

1. Hypothalamus 2. Orbital cortex 3. Parabrachial nucleus 4. Septal area

Question 34

True or False: Olfactory sensory info goes from the olfactory bulb to the amygdala

Answer 34

True

Question 35

Where does auditory, visual, and somatosensory info, which eventually reach the amygdala, come from?

Answer 35

Temporal and Anterior Cingulate Cortices

Question 36

What are the major output pathways of the amygdala?

Answer 36

1) Ventral amygdalofugal 2) Stria terminalis 3) Directly to hippocampus 4) Directly to entorhinal cortex 5) Directly to thalamus 6) Brain stem connections

Question 37

Projects from the ventral striatum links in a basal ganglia circuit that is important for what type of learning?

Answer 37

stimulus-response associative learning

Question 38

The amygdala's major connection to the hypothalamus and septal nucleus is through the ___ ____

Answer 38

stria terminalis

Question 39

True or False: The stria terminalis is important because it acts as a link whereby motivations and drives can influence response / is a link where responses are learned (associative learning)

Answer 39

False - ventral amygdalofugal pathway is important because it acts as a link whereby motivations and drives can influence response / is a link where responses are learned (associative learning)

Question 40

True or False: Stimulation of amygdala causes intense emotions (e.g fear, aggression) while destructive lesions -- as in Urbach-Wiethe--cause flat affect (humans)

Answer 40

True

Question 41

How does the Stria terminalis connect to subcortical structuers?

Answer 41

Via: ventral amygdalofugal pathway

Question 42

True or False: Both hippocampi and amygdala communicate with one another via: anterior commisure

Answer 42

True

Question 43

True or False: The hypothalamus is a principal center of emotional expression and depends on both parasympathetic and sympathetic components of autonomic nervous system

Answer 43

True

Question 44

When we experience feelings/emotions only subjectively, this is related to the ___ ____ A. Amygdala B. Cerebral Cortex C. Hippocampus

Answer 44

B. Cerebral Cortex

Question 45

Emotional reactions or physical expression of emotion are more objective and are mediated through ______ connections A. Amygdala B. Cerebral Cortex C. Hippocampus D. Hypothalamic-autonomic connections

Answer 45

D. Hypothalamic-autonomic connections

Question 46

____ region plays an important role in regulating release of gonadotrophic hormones from the anterior lobe of the pituitary A. Cerebral Cortex B. Preoptic C. Hippocampal

Answer 46

B. Preoptic

Question 47

True or False: In females, gonadotrophic hormones are released in a cyclical manner whereas, in males, the release is topical, with regular fluctuations

Answer 47

True

Question 48

True or False: The ventromedial nucleus is important in male typical behaviors (e.g mounting) while the Preoptic are is important in female typical behaviors (e.g lordosis)

Answer 48

False - preoptic = male typical / VMN = female typical

Question 49

True or False: The sexually dimorphic nucleus (pre-optic area) is large in male rats vs. females

Answer 49

True

Question 50

True or False: INAH-3 is smaller in homosexual men, similar in size to heterosexual females

Answer 50

True

Question 51

True or False: Homosexual men have anterior commisure that were 34% larger than those of heterosexual males and 18% larger than heterosexual females

Answer 51

True

Question 52

True or False: Suprachiasmatic nucleus is smaller in homosexual vs. heterosexual males

Answer 52

False - it is larger

Question 53

Stimulation of the lateral part of the anterior ____ evokes flight responses A. Amygdala B. Hippocampus C. Hypothalamus

Answer 53

C. Hypothalamus

Question 54

Intense stimulation of VM nucleus induces ___, ___

Answer 54

hissing, snarling

Question 55

Stimulation of preoptic area evokes ___ sensation while VM stimulation produces ____ reaction

Answer 55

pleasurable; avoidance

Question 56

______: Contains circadian pacemaker cells, generates endogenous rhythms (influenced by light stimuli) considered to be "master clock"

Answer 56

Suprachiasmic nucleus

Question 57

True or False: The Septum includes both cortical tissue + subcortical nuclei

Answer 57

True

Question 58

Which two pathways can afferents take to reach the septal nuclei?

Answer 58

1) Hippocampal formation - via fornix 2) Amygdala - via: stra terminals

Question 59

Which two pathways can efferents take to reach the septal nuclei?

Answer 59

1) Lateral hypothalamus/midbrain segmentum via medial forebrain bundle 2) Hippocampus via fornix

Question 60

___ ___ function as pleasure center

Answer 60

Septal nuclei