cerebral cortex

Question 1

Every cubic inch of cerebral cortex has about ____ miles of nerve fibers

Answer 1

10,000

Question 2

The number of neurons in the brain is about ___ times greater than the number of humans on the planet

Answer 2

30

Question 3

Typically a neuron is wired to about how many of its neighbors?

Answer 3

1000-2000

Question 4

What is the advantage we have by being good at storing and processing sensory information?

Answer 4

We are better in effective responses to our environment

Question 5

Most cortical neurons are a site of _____ input from multiple neurons

Answer 5

Converging

Question 6

Most cortical neurons are a source of _____ output to multiple neurons

Answer 6

Diverging

Question 7

What is Layer 1 of the cerebral cortex?

Answer 7

Molecular layer; mostly axons

Question 8

What is Layer 2 of the cerebral cortex?

Answer 8

External granule layer

Question 9

What is layer 2 made up of?

Answer 9

Granule (stellate) cells

Question 10

What is the 3rd layer of the cerebral cortex?

Answer 10

External pyramidal layer

Question 11

What is Layer 3 made up of?

Answer 11

Primary pyramidal cells

Question 12

What is layer 4 of the cerebral cortex?

Answer 12

Internal granule layer; main granular cell layer

Question 13

Most incoming sensory signals terminate in which layer of the cerebral cortex?

Answer 13

Layer 4

Question 14

What is layer 5 of the cerebral cortex?

Answer 14

Internal pyramidal layer

Question 15

Layer 5 is dominated by what?

Answer 15

Giant pyramidal cells

Question 16

What is layer 6 of the cerebral cortex?

Answer 16

Multiform layer

Question 17

What types of cells are found in layer 6?

Answer 17

All types; pyramidal, stellate, fusiform

Question 18

Name the 3 major types of cells in the cerebral cortex?

Answer 18

Pyramidal
Granule
Fusiform

Question 19

Which type of cell is a major efferent cell?

Answer 19

Pyramidal

Question 20

____ cells are the least common of the three

Answer 20

Fusiform

Question 21

Which cells give rise to output fibers from cortex?

Answer 21

Fusiform

Question 22

Which cells are a source of cortiospinal projections?

Answer 22

Pyramidal

Question 23

Granule cells have ___ axons

Answer 23

Short

Question 24

Excitatory neurons release what?

Answer 24

1° glutamate

Question 25

What do inhibitory neurons release?

Answer 25

1° GABA

Question 26

Short axons of granule cells function as what?

Answer 26

Interneurons (intra cortical processing)

Question 27

Most output leave the cortex via which layer(s)?

Answer 27

5 and 6

Question 28

Spinal cord tracts originate from layer __

Answer 28

5

Question 29

____ connections are from layer 6

Answer 29

Thalamic

Question 30

Most intracortical association functions are in layer(s) ____

Answer 30

1,2,3

Question 31

All areas of the cerebral cortex has extensive ___ and ___ connections with deeper structures of the brain (eg. Basal ganglia, thalamus)

Answer 31

Afferent; efferent

Question 32

____ connections are extremely important and extensive

Answer 32

Thalamic

Question 33

Which neurons can change their function as functional demand changes?

Answer 33

Cortical neurons