8 - Cerebral Cortex (Exam 2)

Question 1

What is a sulcus?

Answer 1

A “valley” in the cerebral cortex

Question 2

What is a gyrus?

Answer 2

A “peak” in the cerebral cortex

Question 3

What are the 2 major purposes of sulci and gyri?

Answer 3

1. Divide

2. Increase surface area

Question 4

In what way are cortical layers organized based on cell type?

Answer 4

Horizontal rows

Question 5

In what way are cortical layers organized based on function?

Answer 5

Vertical columns

Question 6

Which forms most of the human cortex, the neocortex or the allocortex?

Answer 6

Neocortex

Question 7

What is the allocortex comprised of?

Answer 7

The paleocortex and archicortex

Question 8

What are the 6 layers of the neocortex?

Answer 8

1. I - Molecular layer
2. II - External granular layer
3. III - External pyramidal layer
4. IV - Internal granular layer
5. V - Internal pyramidal layer (Ganglionic layer)
6. VI - Multiform layer

Question 9

Where are pyramidal neurons found?

Answer 9

Layer III

Layer V

Question 10

In what types of functions are pyramidal neurons mainly involved?

Answer 10

Efferent functions

Question 11

Where are granular neurons found?

Answer 11

Layer II

Layer IV

Question 12

In what types of functions are granular neurons mainly involved?

Answer 12

Afferent functions

Question 13

What is another name for granular neurons?

Answer 13

Stellate neurons

Question 14

What are the 2 types of cortical classification?

Answer 14

1. Homotypical cortex

2. Heterotypical cortex

Question 15

Which type of cortical classification makes up the majority of human cortex?

Answer 15

Homotypical cortex

Question 16

What constitutes a classification of heterotypical cortex?

Answer 16

Any area of cortex that doesn’t have six layers

Question 17

What are the 2 types of heterotypical cortex?

Answer 17

1. Granular type

2. Agranular type

Question 18

What is meant by the granular type of heterotypical cortex and where is it typically found?

Answer 18

Granular layers (II and IV) well developed
Auditory cortex, postcentral gyrus, parts of visual cortex

Question 19

What is meant by the agranular type of heterotypical cortex and where is it typically found?

Answer 19

Granular layers (II and IV) poorly developed
Frontal lobe

Question 20

What is the role of association fibers?

Answer 20

Interconnect areas of cortex within the same hemisphere

Therefore no decussation

Question 21

What 2 areas does the superior longitudinal fasciculus connect?

Answer 21

Broca’s area and Wernicke’s area

Question 22

What is another name for the superior longitudinal fasciculus?

Answer 22

Arcuate fasciculus

Question 23

What areas does the inferior occipitofrontal fasciculus connect?

Answer 23

Frontal lobe
Temporal lobe
Occipital lobe

Question 24

What is another name for the inferior occipitofrontal fasciculus?

Answer 24

Uncinate fasciculus

Question 25

What areas does the superior occipitofrontal fasciculus connect?

Answer 25

Frontal lobe Parietal lobe Occipital lobe

Question 26

What is the purpose of the cingulum?

Answer 26

Connects areas of the limbic cortex

Question 27

What is the role of commissural fibers?

Answer 27

Interconnects areas of cortex across both hemispheres | Decussation usually occurs at corpus callosum

Question 28

What is the largest cortical commissure?

Answer 28

Corpus callosum

Question 29

What does the anterior commissure connect?

Answer 29

Anterior temporal lobes and olfactory bulbs

Question 30

What does the posterior commissure connect?

Answer 30

Both pretectal nuclei

Question 31

What compact bundle do the corona radiata converge into and form?

Answer 31

Internal capsule

Question 32

What is the bend of the internal capsule called?

Answer 32

genu

Question 33

How do injuries to primary cortical areas differ from injuries to association cortical areas

Answer 33

Injuries to a primary cortex (ex: primary visual area) result in clear cut, defined deficits Injuries to an association cortex results in less specific deficits like personality changes

Question 34

Where is the primary motor cortex located?

Answer 34

The frontal lobe | Specifically on the precentral gyrus

Question 35

What would a lesion of the PMC present as?

Answer 35

Weakness and/or paralysis

Question 36

What would a lesion of motor association areas present as?

Answer 36

Apraxia Deficit in learned skill without paresis (Unable to brush hair)

Question 37

Where is the primary sensory cortex located?

Answer 37

The parietal lobe | Specifically on the postcentral gyrus

Question 38

Projection fibers come from all parts of the cortex into what?

Answer 38

Corona radiata

Question 39

The left primary motor cortex sends motor output to which side of the body?

Answer 39

Right side

Question 40

The left primary sensory cortex receives sensory input from which side of the body?

Answer 40

Right side

Question 41

What is meant by cortical plasticity?

Answer 41

Cortical representation of the body can change | Based on change in sensory input from particular part or area of the body

Question 42

What would a lesion of the PSC present as?

Answer 42

Deficits in awareness and localization of stimuli

Question 43

What would a lesion of sensory association areas present as?

Answer 43

``` Tactile agnosia (inability to recognize an object by touch) or Astereognosis (inability to recognize object placed in hand) ```

Question 44

Where is the primary visual cortex located?

Answer 44

The occipital lobe | Specifically above and below the calcarine sulcus

Question 45

The left primary visual cortex receives information from which side of the visual field?

Answer 45

Right visual field

Question 46

The superior (above calcarine sulcus) primary visual cortex receives information for which part of the visual field?

Answer 46

Inferior visual field

Question 47

What occurs in the visual association areas?

Answer 47

Higher order processing that gives meaning and interpretation to what we see

Question 48

What would a lesion of the left primary visual cortex present as?

Answer 48

Homonymous hemianopsia of the right visual field

Question 49

What would a lesion of visual association areas present as?

Answer 49

``` Visual agnosia (Inability to recognize familiar objects) Pursuit or saccadic deficits ```

Question 50

Where is the primary auditory cortex located?

Answer 50

Temporal lobe | Specifically deep within lateral sulcus on surface of superior temporal gyrus

Question 51

What would a lesion of the primary auditory cortex present as?

Answer 51

Decreased perception of sound primarily in contralateral ear

Question 52

What would a lesion of auditory association areas present as?

Answer 52

Acoustic verbal agnosia (no ability to interpret words though hearing is intact)

Question 53

What is the frontal association area responsible for?

Answer 53

Planning, adaptation to social norms

Question 54

What is the parietal association area responsible for?

Answer 54

Attention and awareness

Question 55

What is the temporal association area responsible for?

Answer 55

Recognition of stimuli and patterns

Question 56

What kind of lesion would result in left spatial inattention?

Answer 56

Lesion of the right parietal lobe

Question 57

What is prosopagnosia?

Answer 57

Inability to recognize faces

Question 58

Where is Broca's area located and what is its purpose?

Answer 58

Inferior frontal gyrus of frontal lobe | Production of language

Question 59

Where is Wernicke's area located and what is its purpose?

Answer 59

Superior temporal gyrus of parietal/temporal lobe | Comprehension of language

Question 60

What does the arcuate fasciculus join?

Answer 60

Broca's area and Wernicke's area

Question 61

How is aphasia different from aysarthria?

Answer 61

Aphasia is the inability to communicate | Dysarthria is disrupted production due to pharynx, tongue, etc.

Question 62

How does Broca aphasia differ from Wernicke aphasia

Answer 62

With Broca aphasia, the patient will understand what you say but will be unable to respond effectively (gets frustrated) With Wernicke aphasia, the patient will not understand what you are saying (is unaware)

Question 63

Does the arcuate fasciculus have a smaller or larger role in the modern model compared to the classical model?

Answer 63

Smaller role | Not all disorders fit into Broca or Wernicke classifications