Introduction to cerebral cortex

Question 1

What is the name of the fissure that divides the cerebral cortex into left and right hemisphere?

Answer 1

Longitudinal fissure

Question 2

What are gyri and sulci?

Answer 2

Gyri -ridge; Sulci - depression

Question 3

What does Nissl staining of the cortex reveal?

Answer 3

Difference in lamination patterns. Nissl substance: ribosome clustering, including the position of cell bodies.

Question 4

How many layers are there for isocortex(neocortex)?

Answer 4

6

Question 5

How many layers are there for allocortex? Which two parts are included?

Answer 5

3. Paleocortex (olfactory cortex) and archicortex (hippocampus)

Question 6

Layer I

Answer 6

molecular layer, not much cell body, stain light. Lots of axons and dentrites. Lots of synaptic activities.

Question 7

Layer II, III

Answer 7

external granular layers, and external pyramindal layer

Question 8

Which layers are included in the supragranular layer?

Answer 8

Layers I,II, III.

Question 9

What is the other layer of Layer IV?

Answer 9

(Internal) granular layer

Question 10

What is special about Layer IV?

Answer 10

Special type of cell (name), lots of thalamic input, primary sensory information

Question 11

What is included in the infragranular layer?

Answer 11

Layers V (internal pyraminal layer) + VI (fusiform layer)

Question 12

What are the cells in the neocortex?

Answer 12

Glia, astrocytes, oligodendrocytes, microglia. As for neurons - spiny stellate cells, pyramidal cells (main excitory cells) onpyramidal cells (GABA neurons)

Question 13

What are the characteristics of spiny stellate cells?

Answer 13

Only in layer 4, shape like star, dentrites have spines, axons much thinner than dentrites, projecting information vertically to layer2/3 (more than to the deeper layer); excitatory neurons: use glutamates as a transmitter. First stop for the external information coming to cortex

Question 14

What are about pyramidal neurons

Answer 14

Most abundant in cortex, found esp in 1, 2/3, 5 layers. has two dense dentritic areas, one near the somite (basal dentrites+oblique dentrites), one near the layer i (apical dendrite, ending in apical tuft). Relative output is downward (axon direction).

Question 15

Tell me about neurons being “spiny”?

Answer 15

The pyramidal neuron, providing excitatory inputs occur on dendritic spines. Excitatory neurons use glutamate as the NT. Each one typically receives single excitatory input. Constantly changing, remodeling

Question 16

Which layer of neurons providing primary output neurons

Answer 16

Layer 5 pyramidal neurons.

Question 17

What is the major type of neurons in Layer 6?

Answer 17

Thalamic projecting neurons Having basal dentrites, and apical dentrites. The tuft is in layer 4 where it receives input (with the spiny stellate input, thalamic)

Question 18

What is excitotoxicity?

Answer 18

Too mch excitation input to the neuron

Question 19

How might you protect against excitotoxicity?

Answer 19

block excitation, enhance inhibition, and limit action potential

Question 20

Describe the cortical circuit with some inhibitory neurons

Answer 20

1. Thalamic input to layer IV SS cells. 2. SS project to P cells in layer II/III. 3. P cells are highly interconnected and synpase with layer V. 4. Layer V, VI P cells provide the majority of cortical output. 5. Feedforward and feedback inhibition flow of excitatory activity.

Question 21

How does the cortex work?

Answer 21

Compare expectation with reality. Pyramidal neurons integrate top-down (predictive) and bottom-up (perceptive) information.

Question 22

what is the structure of the cerebral cortex called?

Answer 22

columnar, which represents the functional unit of cerebral cortex

Question 23

Is the sensory cortex the pre- or post-central gyrus

Answer 23

Post-

Question 24

What are the structures that connect the right and left hemisphere of the brain?

Answer 24

Corpus callosum and anterior commissure