Limbic System ( Dara Cannon )

Question 1

What is the Limbic System involved in ( 7 )

Basically in emotion, reward, pain and basic survival functions

Answer 1

Fight or Flight 
Memory 
Pleasure
Affection 
Fear 
Expression of Emotion 
Aggression

Question 2

Describe the Papez Circuit ( Route )

Basically to connect hypothalamus to limbic lobe

Answer 2

Hippocampus and Amygdala 
↓
Fornix and Stria Terminalis 
↓ 
Mamillary Bodies 
↓
Mamillothalamic Tract 
↓
Anterior Nucleus of Thalamus and Septal Area 
↓
Cingulum Bundle 
↓ 
Entorhinal or Parahippocampal Gyrus

Question 3

What are commissural fibres

Answer 3

Tracts that connect structures between hemispheres

Question 4

What are projection fibres

Answer 4

Connects cortical sites to distant sites

Eg : Fornix and Stria Terminalis

Question 5

What are association fibres

Answer 5

They are white matter fibres that connect structures within hemispheres
Eg : Arcuate Fasciculus

Question 6

Route into the hippocampus ( Starts from Entorhinal cortex → Hippocampus )

Answer 6

Entorhinal Cortex → Subiculum → CA1, CA2, CA3 → Dentate Gyrus → Alveus, Fimbria and Fornix

Question 7

What does the fornix connect

Answer 7

It connects the hypothalamus to the maxillary bodies

Question 8

What is the function of fornix

Answer 8

Carries info from the hypothalamus and plays a key role in memory

Question 9

What is the function of the amygdala ( 4 )

Vital in learning emotional significance of negative stimulus

Answer 9

Fear
Anger
Recognition of Facial Expressions
Social Cognition

Question 10

Is the amygdala implicated in anxiety disorders

Answer 10

Yes

Question 11

What is a part of the Ventral Amygdalofugal Pathway ( 6 )

Answer 11

PAG
Thalamus
Hypothalamus
Septal Nuclei 
Nucleus Accumbens 
Basal Forebrain

Question 12

Where do you find the septal area in respect to :
anterior commissure
septum pellucidum

Answer 12

• Anterior to the commissure

- Base of the Pellucidum

Question 13

Where does the septal area receive inputs from

Answer 13

Receives input from the fornix and habenula

Question 14

What does a cingulotomy treat

Answer 14

Treats severe depression and OCD

Question 15

Where is the site of DBS in the cingulate gyrus

Answer 15

Subgenual Cingulate ( 24 )

Question 16

What is the 3 other fasciculus that connects the temporal lobe besides stria terminalis and fornix?

Answer 16

Uncinate Fasciculus
Arcuate Fasciculus
Inferior Longitudinal Fasciculus

Question 17

What is the Arcuate Fasciculus involved in
What does it connect
What is it’s direct segment
What is its indirect segment

Answer 17

• Involved in language
• Connects the temporal to frontal and parietal
• Wernicke’s w subcentral gyrus and Broca
• Wernicke’s w inf parietal lobule in turn w Broca’s

Question 18

What is the uncinate fasciculus for

What does it connect

Answer 18

• It is for novel info and valence
• It connects the hippocampus and amygdala to the orbitofrontal cortex
  It also helps link the anterior portion of temporal lobe with the inf frontal gyrus and lower surfaces of frontal lobe

Question 19

What is the purpose of inferior longitudinal fasciculus
What does it connect
What conditions do you get if there is a lesion in this area

Answer 19

• For object and face recognition
• Connects temporal cortices to parietal and occipital lobes
• Lesion would cause visual agnosia ( objects ) and prosopagnosia ( face blindness )