Cerebral cortex

Question 1

Cerebral cortex
Forms the outer layer of cerebral hemisphere
It is a layer that usually contains lots of nerve cell bodies, dendritic arborizations and synaptic connections

Question 2

The cerebral cortex has a laminar alignment – AKA arranged in layers
How many layers are there?

Answer 2

6

Question 3

Question 4

How does one distinguish between the cell layers?

Answer 4

distinguish between the layers based on the size and the shape of the neuronal cell bodies within each cell layer

Question 5

Name the six layers
From superficial to deep

Answer 5

Molecular (plexiform) - layer I
External granular - layer II
External pyramidal - layer III
Internal granular - layer IV
Internal pyramidal - layer V
Multiform (fusiform) - layer VI

Question 6

Molecular (plexiform) - layer I lies directly beneath what?

Answer 6

the pia matter

Question 7

Molecular (plexiform) - layer I
contains which cell types?

Answer 7

Horizontal cells of Cajal-Retzius

Question 8

External granular - layer II
Cell types?

Answer 8

Mostly stellate cells and some small pyramidal cells

Question 9

External pyramidal - layer III
cell types?

Answer 9

Pyramidal cells

Question 10

Internal granular - layer IV
Whats special about this area?

Answer 10

Main cortical input station
Specially developed within the sensory areas

Question 11

Internal granular - layer IV
Cell types?

Answer 11

Mostly stellate cells and a smaller portion of pyramidal cells

Question 12

Internal pyramidal - layer V
Cell types

Answer 12

Medium and large pyramidal cells

Question 13

Internal pyramidal - layer V
Whats special about this area?

Answer 13

Main cortical output station (corticofugal fibres)
Most prominent within the motor cortex
The primary motor cortex contains large Betz cells

Question 14

Multiform (fusiform) - layer VI
Cell types

Answer 14

Mostly fusiform cells, with less dominant pyramidal cells and interneurons

Question 15

PHYLOGENETIC CORTEX

Question 16

Name the phylogenetic cortexes

Answer 16

1. Allocortex:
   - Archicortex
   - Paleocortex
2. Mesocortex
3. Neocortex

Question 17

Allocortex is phylogenetically old, comprises as few as 3 layers (up to 5 layers)

Question 18

The allocortex further subdivides into:

Answer 18

Archicortex
Paleocortex

Question 19

Archicortex (ancient cortex: eg, hippocampus)

Answer 19

Consists of only three cellular layers: polymorphic, pyramidal and the molecular

It is associated with the limbic system, specifically with the hippocampal formation, meaning it is involved with emotional expression and memory

Question 20

Paleocortex – younger than archicortex

Answer 20

Consist of three to six layers
Located within the parahippocampal gyrus (entorhinal cortex), uncus (piriform cortex) and lateral olfactory gyrus, meaning it mediates the sense of smell

Question 21

Mesocortex

Answer 21

Represents transitional cortex between neocortex and allocortex Contains three to six layers
Comprises the cingulate gyrus and the remainder of the
parahippocampal gyrus

Question 22

Neocortex (aka isocortex)

Answer 22

Is phylogenetically new, and comprises six histologically distinct layers
It constitutes roughly 90% of the cerebral cortex

Question 23

FUNCTIONAL ORGANIZATION

Question 24

Posterior cerebrum

Answer 24

Question 25

Medial limbic

Answer 25

Question 26

Anterior cerebrum

Answer 26

Question 27

Areas of association cortex in frontal, parietal and temporal lobes of the left hemisphere are responsible for the

Answer 27

comprehension and expression of language