Lecture 36- Cortex 1

Question 1

What is another name for the lateral sulcus?

Answer 1

sylvian fissure

Question 2

What is the defining feature of a neocortex?

Answer 2

it has 6 layers

Question 3

What is the defining feature of an allocortex?

Answer 3

it has less than 6 layers

Question 4

Where can allocortex be found?

Answer 4

limbic areas- hippocampus, entorhinal area etc

Question 5

What is the principal cell in the cerebral cortex?

Answer 5

pyramidal cell

Question 6

Is the pyramidal cell excitatory or inhibitory? What neurotransmitter does it produce?

Answer 6

excitatory, produces glutamate

Question 7

In what layers of the cortex would the pyramidal cells be found?

Answer 7

Layers 2,3 and 5,6 (layer 1 is mostly acellular and layer 4 is spiny stellated)

Question 8

Where does the apical dendrite of the pyramidal cell project?

Answer 8

to the pial surface (layer 1)

Question 9

Where does the axon of the pyramidal cell project?

Answer 9

down towards the white matter

Question 10

What is special about the apical dendrite and basal dendrites of the pyramidal cell?

Answer 10

they are covered with spines

Question 11

What is the name given to the cells in layer 4 of the cortex that look similar to pyramidal cells but lack an apical dendrite?

Answer 11

spiny stellate cells

Question 12

What layer of the cortex houses spiny stellate cells?

Answer 12

layer 4

Question 13

What differentiates spiny stellate cells from pyramidal neurons?

Answer 13

spiny stellate cells are lacking an apical dendrite

Question 14

Are spiny stellate cells excitatory or inhibitory?

Answer 14

excitatory-gluatamate-dendritic spines

Question 15

Are chandelier and basket cells excitatory or inhibitory?

Answer 15

GABAergic-inhibitory

Question 16

Where do basket cells synapse on the pyramidal neuron?

Answer 16

cell body

Question 17

What is contained within layer 1 of the cerebral cortex?

Answer 17

layer 1- molecular layer- mostly acellular- contains apical tufts of pyramidal neurons (from 2,3 and 5,6)

Question 18

What is found in layers 2,3 of the cerebral cortex?

Answer 18

small and medium pyramidal cells that project locally

Question 19

What is found in layer 4 of the cortex?

Answer 19

spiny stellate cells that receive input from the thalamus

Question 20

What layers receive input from the thalamus?

Answer 20

Primarily layer 4 with some collateral to layers 3 and 6

Question 21

What defines a granular cortex?

Answer 21

prominent layer 4 (ex. Somatosensory cortex)

Question 22

What defines an agranular cortex?

Answer 22

lacking a prominent layer 4 (ex. primary motor cortex)

Question 23

Where are Betz cells found?

Answer 23

Layer 5 of the the primary motor cortex (they form the corticobulbar tracts)

Question 24

Where do the axons that form the corticobulbar tract originate?

Answer 24

Layer 5 Betz Cells of the primary motor cortex

Question 25

What does the weigert stain do?

Answer 25

stains myelin bundles

Question 26

What is Brodmann’s area 4?

Answer 26

primary motor cortex

Question 27

What is the Brodmann’s area for the primary motor cortex?

Answer 27

4

Question 28

What is Brodmann’s area 17?

Answer 28

primary visual cortex

Question 29

What is Brodmann’s area 41 and 42?

Answer 29

auditory cortex

Question 30

What is Brodmann’s area 1,2,3?

Answer 30

Somatosensory cortex

Question 31

Where does thalamic input to the cortex terminate?

Answer 31

Layers 4, 3, 6

Question 32

Where does callosal (between hemispheres) input terminate in the cerebral cortex?

Answer 32

Layer 3

Question 33

Where do projects from layer 5 go?

Answer 33

subcortical areas (ex. superior colliculus)

Question 34

Which layer of the cerebral cortex projects to subcortical structures like the superior colliculus?

Answer 34

layer 5

Question 35

Which layer of the cerebral cortex projects back to the thalamus to provide feedback?

Answer 35

layer 6

Question 36

Where do axons from layer 6 project to?

Answer 36

thalamus

Question 37

In what layer of the striate cortex is the Stripe of Gennari found?

Answer 37

Layer 4B

Question 38

Where do chandelier cells synapse on pyramidal cells?

Answer 38

axon initial segment