Exam 3 Cortex and Cortical Localization

Question 1

From which cortical layer do Callosal Fibers originate?

Answer 1

Layer III. These are long-association fibers.

Question 2

What are Betz Cells?

Answer 2

Large pyramidal cells in Layer V

Question 3

What type of innervation do Pyramidal Cells provide?

Answer 3

Excitatory via Glutamate

Question 4

What cortical layer(s) are Pyramidal Cells found in?

Answer 4

All layers except I

Question 5

Which cortical layers contain predominately Pyramidal Cells?

Answer 5

Layers II, III and V

Question 6

Which is the most common neuron cell-type in the cerebral cortex?

Answer 6

Pyramidal Cells

Question 7

From which cell-type do projection axons originate?

Answer 7

Pyramidal Cells

Question 8

In which cortical layer are Chandelier Cells found?

Answer 8

Layer III

Question 9

In which cortical layer are Spiny and Aspiny Cells found?

Answer 9

Layer IV

Question 10

In which cortical layers are Basket Cells found?

Answer 10

Layers III, V

Question 11

What type of innervation do Granule Cells provide?

Answer 11

Mostly inhibitory

Question 12

In which layers is the Band of Baillerger found?

Answer 12

Layers IV and V

Question 13

What is the Band of Baillerger?

Answer 13

A tract of horizontal cortical fibers running in layers IV and V

Question 14

From which layer do Interhemispheric axons originate?

Answer 14

Layer III

Question 15

Which cortical regions are connected by the Corpus Callosum?

Answer 15

Left and Right hemispheres, excluding the temporal poles

Question 16

Which cortical regions are connected by the Anterior Commissure?

Answer 16

The Temporal Poles

Question 17

Which tract connects the Temporal Poles?

Answer 17

The Anterior Commissure

Question 18

Which tract connects the L and R Hemispheres?

Answer 18

The Callosal Tract

Question 19

From which layer(s) do Intrahemispheric axons originate?

Answer 19

Layers II, III, IV

Question 20

What are the two types of Intrahemispheric axons?

Answer 20

Long Association Axons, Short Association Axons

Question 21

From which layers do Long Association Axons originate?

Answer 21

Layers III and IV

Question 22

From which layer do Short Association Fibers originate?

Answer 22

Layer II

Question 23

Which cortical structures are connected by Long Association Fibers?

Answer 23

Lobes and Lobules

Question 24

Which cortical structures are connected by Short Association Fibers?

Answer 24

Gyri

Question 25

Which cortical structures are connected by Local Intrinsic Axons?

Answer 25

Cortical Layers

Question 26

Which cortical structures are connected by Local Circuit Axons?

Answer 26

Columns

Question 27

From which cortical layer does Corticothalamic Fibers originate?

Answer 27

Layer VI

Question 28

From which cortical layers do Corticobulbar Fibers originate?

Answer 28

Layers III and V

Question 29

From which cortical layers do Coriticospinal Fibers originate?

Answer 29

Layers III and V

Question 30

From which cortical layer do Corticostriate Fibers originate?

Answer 30

Layer V

Question 31

From which cortical layer do Corticopontine Fibers originate?

Answer 31

Layer V

Question 32

To which cortical layers do Thalamocortical Fibers from specific thalamic nuclei project?

Answer 32

Layer IV

Question 33

To which cortical layers do Thalamocortical Fibers from intralaminar thalamic nuclei project?

Answer 33

Layers II and III

Question 34

When are all cortical neurons formed?

Answer 34

First half of embryonic gestation

Question 35

To which cortical layers do subcortical nuclei project?

Answer 35

All layers, with diffuse inputs

Question 36

What provides the signals for induction of neuroblast migration in the developing cerebral cortex?

Answer 36

NA axons arriving in the plexiform zone

Question 37

What type of cells are found in Cortical Layer I?

Answer 37

NONE! TRICK QUESTION, BITCH! - Jesse Pinkman

Question 38

How does Lissencephaly relate to neuronal migration?

Answer 38

Absence of Layer II and reduction of Layers III and IV

Question 39

What is the cortical region that mediates motor functions of speech?

Answer 39

Broca's Area located in the inferior frontal gyrus. Pars Triangularis and Pars Opercularis.

Question 40

Describe the effects of small lesions to V1

Answer 40

scotomas in the CONTRALATERAL visual field

Question 41

Describe the effects of large lesions to V1

Answer 41

quadrantopsia or hemianopsia in the CONTRALATERAL visual field

Question 42

Describe the origin and type of input to dorsal V3

Answer 42

Large scale motion from V1 and V2 (Where)

Question 43

Describe the origin and type of input to ventral V3

Answer 43

Object recognition from V2 (What)

Question 44

Where does the LEFT ventral visual stream travel and what modalities does it carry?

Answer 44

V1 + V2 --> V3 --> V4 --> Posterior Inferior Temporal Lobe, area IT. It carries object recognition information.

Question 45

Where does the LEFT ventral visual stream terminate and what is this area responsible for?

Answer 45

Left Posterior Inferior Temporal Lobe. This area processes feature information like color, texture and shape.

Question 46

Where does the RIGHT ventral visual stream terminate and what is this area responsible for?

Answer 46

Right Posterior Inferior Temporal Lobe. This area processes holistic, non-verbal perception, including face recognition.

Question 47

What might cause Visual Form Agnosia?

Answer 47

A lesion of the ventromedial occipitotemporal cortex (lingual and fusiform gyri)

Question 48

What might cause Alexia and Agraphia

Answer 48

Lesion of the Left Posterior Inferior Temporal Lobe

Question 49

What would result from a lesion of the Left Posterior Inferior Temporal Lobe?

Answer 49

Alexia with Agraphia, the inability to communicate through written words

Question 50

What would result from a lesion of the ventromedial occipitotemporal cortex?

Answer 50

Visual Form Agnosia, the inability to recognize objects

Question 51

Where does the dorsal visual stream travel and what modalities does it carry?

Answer 51

V1-->V2-->V3-->V5 (MT)--> Frontal Eye Fields and Posterior Parietal Cortex. It is involved in assemblage of objects in visual space and motion perception. So-called "where"

Question 52

Where does the dorsal visual stream terminate and what are these areas responsible for?

Answer 52

Frontal Eye Fields (Frontal Lobe) and Posterior Parietal Cortex. These areas process spacial visual information.

Question 53

What is Balint's Syndrome?

Answer 53

Simultanagnosia, optic ataxia, ocular apraxia. Bilateral lesion to the posterior parietal cortex.

Question 54

What might result from a watershed MCA/PCA stroke in the posterior parietal cortex?

Answer 54

Balint's Syndrome: simultanagnosia (inability to see more than one object at a time), optic ataxia (inability to move hand towards object), ocular apraxia (inability to voluntarily gaze at an object).

Question 55

Where is the Primary Auditory Cortex located?

Answer 55

Heschl's Gyrus (dorsal opercular aspect of temporal lobe)

Question 56

What tract delivers fibers from MGN?

Answer 56

Sublenticular tract, main auditory radiation

Question 57

Where is the LEFT auditory belt and what does it do?

Answer 57

A ring of cortex surrounding the primary auditory cortex (Heschl's gyrus). It processes temporal aspects of sound.

Question 58

Where is the RIGHT auditory belt and what does it do?

Answer 58

A ring of cortex surrounding the primary auditory cortex (Heschl's gyrus). It processes spectral (musical) aspects of sound.

Question 59

Where is Wernicke's area located?

Answer 59

Left Posterior Superior Temporal Gyrus

Question 60

What function does Wernicke's area serve?

Answer 60

Left: Interpreting verbal properties of language

Question 61

What function does the Posterior Superior Temporal Gyrus serve on the RIGHT hemisphere?

Answer 61

Interpreting Prosody of the spoken word

Question 62

What might lead to sensory aphasia?

Answer 62

Damage to Wernicke's area on the LEFT

Question 63

What might result from a lesion in Wernicke's area?

Answer 63

Sensory aphasia. The inability to communicate verbally. Pt's can speak but can't interpret words.

Question 64

What might result from a lesion on the RIGHT Superior Temporal Gyrus?

Answer 64

Sensory aprosodia. An inability to detect humor or sarcasm (prosodic) elements in speech.

Question 65

What causes sensory aprosodia?

Answer 65

Lesion to the Right Superior Temporal Gyrus

Question 66

What causes sensory aphasia?

Answer 66

Lesion to the Left Superior Temporal Gyrus (Wernicke's area)

Question 67

Where is the recognition of words and their meaning processed?

Answer 67

more anterior lateral and inferior parts of the temporal lobe. Information gets more specific closer to the temporal pole (i.e., from categories to proper nouns)

Question 68

What might result from a lesion of the RIGHT Lateral and Inferior Temporal Cortex?

Answer 68

Inability to retrieve the name of an object based on non-verbal information pertaining to these objects

Question 69

What might result from a lesion of the LEFT lateral and Inferior Temporal Cortex?

Answer 69

Anomia: Inability to recall the names of objects. Increases in severity the closer the lesion is to the temporal pole.

Question 70

What might cause unilateral agraphesthesia and astereognosis?

Answer 70

Lesion to the postcentral gyrus

Question 71

Will a lesion to the postcentral gyrus lead to complete loss of pain and thermal sensation?

Answer 71

No. Only a diminution.

Question 72

What might result from a lesion to the postcentral gyrus?

Answer 72

Agraphesthesia (inability to recognize shapes drawn on palms of hands or body) and astereognosis (inability to recognize objects via tactile sensations)

Question 73

What might result in construction apraxia?

Answer 73

Lesion to the RIGHT dorsomedial parietal lobe

Question 74

What might result in tactile agnosia (the inability to recognize objects by touch or name them?)

Answer 74

Lesion to the ventromedial parietal lobe

Question 75

What might result from a lesion to the RIGHT Inferior Parietal Lobule?

Answer 75

hemispatial neglect on the LEFT side

Question 76

What might result from a lesion to the LEFT Inferior Parietal Lobule?

Answer 76

Agraphia, Acalculia, Finger Agnosia and Left-Right Confusion. All four signs: Gerstmann's Syndrome