Limbic System

Question 1

anterior nucleus of the thalamus projects where?

Answer 1

to the cingulate gyrus

Question 2

the limbic gyrus is main of what brain components?

explain.

Answer 2

• made of:
  
  • cingulate gyrus
  • parahippocampal gyrus

the cingulate gyrus curves along the corpus collusum and, on the the inferior surface of the brain, curves into the parahippocampal gyrus (up to the uncus)

Question 3

the hippocampus is - present in what parts of the brain?

Answer 3

• starts at dentate nucleus (region superior to the uncus) and extends ventrally
  
  • dentate gyrus: head of hippocampus
  • parahippocampus: most of hippocampus
  • cingulate gyrus: tail of hippocampus

Question 4

where is the denate nucleus located?

why is it significant?

Answer 4

superior to the uncus

contains the head othe hippocampus

Question 5

uncus

• location
• anatomical relations
• histology

Answer 5

• portion of temporal lobe rostral to the parahippocampal gyrus
• is in a horizantal plane with the mamillary bodies, and points towards them medially
• histology: 3 cell layers (like the rest of hiccocampus) vs rest of brain, which is six

Question 6

cerebral cortex vs hippocampus histology

Answer 6

• cerebral cortex - 6 layers
• hippocampus - 3 layers

Question 7

the fornix

• is formed by what?
• is located where?
• attaches how?

Answer 7

• formed by: fimbrae
  
  • fibers on the superomedial hippocampus surface that
  • form a crus, which then
  • fuse to form the body of the fornix
• location: body suspended on the inferior edge of the septum pellucidum
• travels: rostrally, approaching the anteiror commissure

Question 8

at the anterior commisure, the fornix splits to form what two components?

Answer 8

• anterior component
• posterior component

Question 9

the anterior component of the fornix extends to…?

Answer 9

• two basal forebrain nuclei (frontal lobe inferior brain rostral to hypothalamus)
  
  • septal nucleui
  • nucleus accumbens

Question 10

the posterior component of the fornix extends to…?

Answer 10

• the hypothalamus
• mamillary bodies

Question 11

the mamillary bodies

• primarily receive input from?
• primary deliver output to?

Answer 11

• input: posterior component of the fornix
• output: thalamic anterior nucleus via mamillothalamic tract