Anatomy MNTH

Question 1

What are the four non cortical structures of the Limbic System?

Answer 1

Hippocampus formation
Amygdala
Septal area
Hypothalamus

Question 2

What are the limbic functions of these structures?

Hypothalamus
Olfactory cortex
Hippocampus
Amygdala

Answer 2

Homeostatic function
Olfaction (smell)
Memory
Emotion and drives

Question 3

How is the hippocampus divided and which area is most susceptible to anoxia (Low O2)?

Answer 3

It is divided into 4 fields. CA1-CA4

CA1 (Sommer’s sectors) is most susceptible to anoxia especially during times of temporal epilepsy.

Question 4

What region of the brain provides the major input to the hippocampus?

Answer 4

Enterrorhinal

Question 5

What are the 3 components of the fornix system and the brain regions to which they connect the hippocampus?

Answer 5

Precommissural Fornix: Septal Area

Postcommissural Fornix: Diencephalon

Commissural component: terminate in contralateral hippocampus

Question 6

What are the 2 major thalami nuclei that connect the limbic system?

Answer 6

Mediodorsal

Anterior

Question 7

What are the 3 main function of the hippocampus formation?

Answer 7

Learning and memory

Modulates aggressive behavior

Modulates endocrine functions

Question 8

How does the hippocampus modulate aggressive behavior

Answer 8

Activation of the HF closest to the amygdala facilitates aggression

Activation of the HF closest to the septal pole suppresses the aggression

Question 9

Which component of the HF regulates the hypothalamic-pituitary-adrenal axis?

Answer 9

The medial corticohypothalamic tract: It is a direct pathway to the ventromedial hypothalamus arising from the subiculum.

Question 10

What are the 3 areas that make up the Parahippocampal Gyrus?

Answer 10

Entorhinal cortex
Parahippocampal cortex
Perirhinal cortex

Question 11

What happens when the Parahippocampal Gyrus?

Answer 11

Loss in the ability to form new memories

Inability to recognize scenes although the objects can be recognized.

Question 12

What are the parts of the Papez Circuit?

Answer 12

Hippocampus
Fornix
Mammillary Body
Mammillothalamic tract
Anterior thalami nuclei
Thalamocingular tract
Cingulate Gyrus
Cingulohippocampal fibers
Hippocampus

Question 13

What are the functions of the septal area?

What would happen if a lesion happened there?

Answer 13

Relay between the hippocampal formation and the hypothalamus

Also plays a part with rage, drinking, and suppressing ACTH

A lesion will increase the release of ACTH.

Question 14

What is the function of the Bed nucleus of stria terminalis?

Answer 14

Believed to regulate autonomic, endocrine, and affective processes

Question 15

What is the function of the nucleus accumbens?

Answer 15

Integrate the sequencing of motor responses associated with affective processes as well.

Question 16

What are the connections of the substantia Innominate to the limbic system?

Answer 16

May be a relay of parts of the amygdala to the lateral hypothalamus.

Question 17

What is the syndrome and symptoms of amygdala ablation?

Answer 17

Kluver-Bucy Syndrome

Hyper sexuality
Excessive eating
Aggression
Visual agnosia
Oral exploration
Less fear

Question 18

Where does the Amygdala receive its input from?

Answer 18

Olfactory
Taste
Temporal neocortex (sound)
Substantia Innominate 
Diagonal band of Brock
Ventromedial hypothalamus

Question 19

What are the 2 major efferent pathways of the amygdala?

Answer 19

To the hypothalamus and periaquaductal gray via ventral amygdalofugal pathway.

Prefrontal cortex via the ventral amygdalafugal pathway

Question 20

What do the corticomedial nuclei vs the basolateral nuclei of the amygdala do?

Answer 20

CMN 1st, BLN 2nd

Stimulate aggression vs pacify

Inhibit feeding and drinking vs Facilitate it

Simulate ovulation vs None

Inhibits GH release vs Facilitate release

Inhibits release of ACTH vs Facilitate release

Question 21

What are the 2 thalami nuclei that connect the basal nuclei to the limbic system?

Answer 21

Mediodorsal

Ventral anterior