The Forebrain and Midbrain

Question 1

the Cerebral Cortex can be divided into…

Answer 1

the Neocortex,
the Olfactory Cortex,
and the Hippocampus.

Question 2

the Neocortex has key sulci and gyri that can identify 4 main lobes…

Answer 2

the lateral sulcus,
the central sulcus,
the pre-central gyrus,
and the post-central gyrus.

Question 3

where is the lateral sulcus located?

Answer 3

it separates the temporal lobe and the frontal lobe.

Question 4

where is the central sulcus located?

Answer 4

it separates the frontal lobe from the parietal lobe.

Question 5

where is the pre-central gyrus located?

Answer 5

it is in front of the central sulcus.

Question 6

where is the post-central gyrus located?

Answer 6

it is behind the central sulcus.

Question 7

how many layers does the Neocortex have?

Answer 7

6 layers.

Question 8

what is the first layer of the Neocortex (towards the outside / neural tissue layer)?

Answer 8

the molecular layer.

Question 9

what is the second layer of the Neocortex?

Answer 9

the external granular layer.

Question 10

what is the third layer of the Neocortex?

Answer 10

the external pyramidal layer.

Question 11

what is the fourth layer of the Neocortex?

Answer 11

the internal granular layer.

Question 12

what is the fifth layer of the Neocortex?

Answer 12

the internal pyramidal layer.

Question 13

what is the sixth layer of the Neocortex (deeper into the brain)?

Answer 13

the fusiform layer.

Question 14

how can we map the Neocortex?

Answer 14

using Brodmann’s cytoarchitectural map, and using lesions and direct stimulation.

Question 15

what are non-invasive methods to map the Neocortex?

Answer 15

brain scanning - PET, fMRI, EEG.

Question 16

the Hippocampus is found where? and has how many layers of cortex?

Answer 16

the Hippocampus is found in the temporal lobes and have only 3 layers of cortex.

Question 17

the Thalamus is found where?

Answer 17

the Thalamus is found in the diencephalon, and has over 50 nuclei.

Question 18

how is the Thalamus important?

Answer 18

is a big relay station for information, connecting to the Neocortex via projection fibres.

Question 19

the Hypothalamus is found where?

Answer 19

it is around the third ventricle, and has 11 major nuclei.

Question 20

how is the Hypothalamus important?

Answer 20

it is a master regulator for homeostasis, and links to ANS and the pituitary.

Question 21

the dorsal aspect of the Midbrain can be divided into…

Answer 21

the superior colliculus (in rostral midbrain),

and the inferior colliculus (in the caudal midbrain).

Question 22

what sensory info is processed in the superior colliculus?

Answer 22

visual information.

Question 23

what sensory info is processed in the inferior colliculus?

Answer 23

auditory information.

Question 24

the Midbrain is also made up of pathways involved in voluntary movements:

Answer 24

the substantia nigra and the red nucleus.

Question 25

the Midbrain also has the cerebral aqueduct - how is this important?

Answer 25

the cerebral aqueduct is surrounded by periaqueductal grey tissue which is involved in the perception of pain.