Major White Matter Areas on the Medial Surface of the Brain

Question 1

What is the corpus callosum?

Answer 1

A broad arched band of white matter- the largest of the fibre bundles interconnecting the two halves of the brain

Question 2

What is the genu?

Answer 2

The anterior curved end of the corpus callosum

Question 3

Where is the rostrum?

Answer 3

It leads downwards from the genu of the corpus callosum

Question 4

What is the body?

Answer 4

The main central curve of the corpus callosum

Question 5

What is the splenium?

Answer 5

The rounded posterior end of the corpus callosum

Question 6

What is the fornix?

Answer 6

A bundle of white matter beneath the body of the corpus callosum, it connects the hippocampus with the diencephalon and the precommissural septum

Question 7

What happens at the commussure of the fornix?

Answer 7

FIbres from one hippocampus cross to the opposite fornix and so back to the opposite hippocampus

Question 8

What are the columns of the fornix?

Answer 8

Anterior and posterior extensions of the fornix, anteriorly they extend vertically downwards to the mammillary bodies

Question 9

What is the anterior commisure?

Answer 9

A thick bundle of white matter corssing the midline horizontally between the lamina terminalis and the fornix, crosses to interconnect the temporal lobes and olfactory structures on each side

Question 10

What is the septum pellucidum?

Answer 10

Two thin vertical sheets made of glia with a few white fibres, sparse grey matter and a covering of ependymya at the anterior and inferior border of the corpus callosum from the fornices

Question 11

What is the lamina terminal?

Answer 11

a thin sheet of ependyma and pia which extends downwards from the rostrum of the callosum and fornix to the anterior walll of the 3rd ventricle