Neuro: 4.1 - Cerebral Cortex

Front 1

What is the cerebral cortex embryologically derived from?

Back 1

Telencephalon

Front 2

Where does input to the Cerebral Cortex come via? Output to?

Back 2

- Input all channels through Thalamus
- Output to Basal Ganglia, Thalamus, Brain Stem, and Spinal Cord

Front 3

How can the Cerebral Cortex be subdivided?

Back 3

- Archicortex (3 layers; includes hippocampus and dentate gyrus)
- Paleocortex (includes olfactory cortex)
- Neocortex (6 layers)

Front 4

What are the Hippocampus and Dentate Gyrus a part of?

Back 4

Archicortex - component of the Cerebral Cortex

Front 5

What is the Olfactory Cortex a part of?

Back 5

Paleocortex - component of the Cerebral Cortex

Front 6

What are the poles of the Cerebral Cortex?

Back 6

- Frontal
- Temporal
- Occipital

Front 7

What are the lobes of the Cerebral Cortex?

Back 7

- Frontal Lobe
- Parietal Lobe
- Temporal Lobe
- Occipital Lobe
- Insula and Limbic Lobes = subdivisions

Front 8

What are the components of the Frontal Lobe of the Cerebral Cortex?

Back 8

- Precentral gyrus
- Superior frontal gyrus
- Middle frontal gyrus
- Inferior frontal gyrus: Opercular, Triangular, and Orbital
- Prefrontal cortex
- Orbital gyrus
- Gyrus rectus

Front 9

What are the components of the Parietal Lobe of the Cerebral Cortex?

Back 9

- Postcentral gyrus
- Superior parietal lobule
- Inferior parietal lobule: Supramarginal gyrus and Angular gyrus
- Precuneus
- Paracentral lobule (posterior part)

Front 10

What are the components of the Temporal Lobe of the Cerebral Cortex?

Back 10

- Superior temporal gyrus
- Middle temporal gyrus
- Inferior temporal gyrus
- Occipitotemporalgyrus or Fusiform gyrus
- Parahippocampal gyrus
- Hippocampus

Front 11

What are the components of the Occipital Lobe of the Cerebral Cortex?

Back 11

- Lateral Occipital gyrus
- Cuneus gyrus and Lingual gyrus
- Occipitotemporal gyrus

Front 12

What are the components of the Limbic Lobe of the Cerebral Cortex?

Back 12

- Cingulate Gyrus
- Parahippocampal Gyrus
- Hippocampus

Front 13

What arteries supply the Cerebral Cortex with blood?

Back 13

Components of Circle of Willis:
- Anterior Cerebral A.
- Middle Cerebral A.
- Posterior Cerebral A.
- Anterior Communicating A.
- Posterior Communicating A.

Front 14

What sinuses drain the Cerebral Cortex?

Back 14

- Superior Sagittal Sinus
- Inferior Sagittal Sinus
- Straight Sinus
- Transverse Sinuses
- Sigmoid Sinuses
- Drain into Internal Jugular Veins

Front 15

What are the 6 cellular layers of the Neocortex (the majority of the cortex)?

Back 15

1. Molecular Layer
2. External Granular Layer
3. External Pyramidal Layer
4. Internal Granular Layer
5. Internal Pyramidal Layer
6. Multiform Layer

Front 16

What are the horizontal bands and vertical bundles in the Cerebral Cortex?

Back 16

Myelinated axons (e.g., especially in visual cortex)

Front 17

What are the major cell types in the Cerebral Cortex?

Back 17

Pyramidal and Non-pyramidal

Front 18

What are the structures that form functional units in the Cerebral Cortex?

Back 18

Columns and Modules

Front 19

What is the organization of the "Columns and Modules" of the Cerebral Cortex?

Back 19

- Each column extends through the 6 layers that share similar functions
- Functional columns form modules in various cortical areas, esp. the primary somatosensory, visual, and auditory cortices
- Columns of cortical neurons are interconnected within the same hemisphere and between the two hemispheres

Front 20

What are the important Brodmann's areas? Location?

Back 20

- Areas 3, 1, 2: Postcentral Gyrus - Primary Somatosensory Cortex (RED)
- Area 4: Precentral Gyrus - Primary Motor Cortex (BLUE)
- Area 17: Cuneus and Lingual Gyri - Primary Visual Cortex (GREEN)
- Areas 41, 42: Transverse Gyri of Heschl - Primary Auditory Cortex (YELLOW)
- Areas 44, 45: Inferior Fronal Gyrus - motor area of speech (Broca's area) - primarily in L hemisphere (NAVY)

Front 21

What is the location of Brodmann's Areas 3, 1, and 2? Features?

Back 21

- Postcentral Gyrus
- Primary Somatosensory Cortex
(RED)
- Somatotopic organization (contralateral) - sensory homunculus
- Increased representation of face and hand; lower limb is medial

Front 22

What is the location of Brodmann's Area 4? Features?

Back 22

- Precentral Gyrus
- Primary Motor Cortex
(BLUE)
- Somatotopic organization (contralateral) - motor homunculus
- Increased representation of face and hand; lower limb is medial

Front 23

What is the location of Brodmann's Area 17? Features?

Back 23

- Cuneus and Lingual Gyri
- Primary Visual Cortex
(GREEN)
- Visuotopic organization
- Central VF - most posterior
- Peripheral VF - most anterior
- Vertical meridian - at border of areas 17/18
- Horizontal meridian - bisect horizontally

Front 24

What is the location of Brodmann's Areas 41 and 42? Features?

Back 24

- Transverse Gyri of Heschl
- Primary Auditory Cortex
(YELLOW)
- Tonotopic organization
- Binaural representation

Front 25

What is the location of Brodmann's Areas 44 and 45? Features

Back 25

- Part of Inferior Frontal Gyrus
- Motor area of speech (Broca's Area) - mostly dominant in left hemisphere
(NAVY)

Front 26

What happens if there is a lesion to the Postcentral gyrus? What Brodmann's Area is this?

Back 26

Contralateral loss of somesthetic sensation - Areas 3, 1, and 2 (RED)

Front 27

What happens if there is a lesion to the Precentral gyrus? What Brodmann's Area is this?

Back 27

Contralateral spastic paralysis - Area 4 (BLUE)

Front 28

What happens if there is a lesion to the Cuneus and Lingual gyri? What Brodmann's Area is this?

Back 28

- Contralateral hemianopia
- If restricted to upper or lower banks of the Calcarine fissure --> contralateral inferior or superior quadrantanopia
- Area 17 (GREEN)

Front 29

What happens if there is a lesion to the Transverse gyri of Heschl? What Brodmann's Area is this?

Back 29

Bilateral lesions lead to loss of hearing
Areas 41 and 42 (ORANGE)

Front 30

What happens if there is a lesion to the Broca's area? What Brodmann's Area is this?

Back 30

- Dominant side (left) - motor aphasia, Broca's aphasia, or expressive aphasia
- Non-dominant side (right) - difficulty expressing emotional aspect of language
- Areas 44 and 45 (NAVY)

Front 31

What are the main functional areas of the Frontal Cortex?

Back 31

- Primary motor cortex: area 4
- Premotor cortex: area 6
- Supplementary motor cortex
- Frontal eye field
- Broca’s area
- Limbic orbitofrontal cortex
- Prefrontal cortex

Front 32

What happened to Phineas Gage?

Back 32

- Destroyed much of left prefrontal lobe
- Partial paralysis of left side of face
- Loss of vision in left eye
- Ptosis in left eye
- Survived for 12 years
- Major personality and mental changes

Front 33

What are the structures in the association cortical areas of the parietal lobe?

Back 33

- Posterior parietal lobe: polymodal convergence - determining where something is
- Superior parietal lobule (areas 5 and 7)
- Inferior parietal lobule (supramarginal gyrus - area 40; angular gyrus - area 39)

Front 34

What happens when there are lesions to the association cortical areas of the parietal lobe?

Back 34

- Dominant (usually left) hemisphere --> astereognosis - inability to identify an object by touch without visual input (area 40) & Aphasia (inability to express or understand language) / Alexia (inability to read) / Agraphia (inability to write) (area 39)
- Non-dominant (usually right) hemisphere --> spatial distortion and contralateral neglect (ignore L side of body or draw only R half of picture)

Front 35

What are the components of the association cortical areas of the occipital lobe?

Back 35

- Secondary visual cortex: area 18 or V2
- Association cortical areas: V3, V4, etc.
- 32 visual areas in primate (occipital, parietal, and temporal)

Front 36

What happens if there are lesions to the association cortical areas of the occipital lobe?

Back 36

Variety of visual deficits

Front 37

What are the components of the association cortical areas of the temporal lobe?

Back 37

Wernicke's Area - posterior part of superior temporal gyrus (area 22) - language comprehension (dominant on L)

Front 38

What happens if there are lesions to the association cortical areas of the temporal lobe?

Back 38

- Wernicke's area (dominant hemisphere, L) --> sensory aphasia, Wernicke's aphasia, or receptive aphasia
- Wernicke's area (non-dominant hemisphere, R) --> difficulty in comprehending the emotional aspect of language

Front 39

What kind of fibers connect different parts of the cortex to each other?

Back 39

- Short Association Fibers - within same hemisphere
- Long Association Fibers - within same hemisphere
- Callosal Fibers - via corpus callosum to opposite hemisphere

Front 40

What are the general functions of the cerebral cortex?

Back 40

- Perception of special sensations - somatic, visual, auditory, olfaction (cortical maps for each of the major senses)
- Planning and execution of voluntary movements
- Emotions and behavior
- Mental functioning
- Memory

Front 41

What can cause dysfunction of the cerebral cortex?

Back 41

- Vascular hemorrhage, thrombosis, or tumor
- Tumors usually of glial origin

Front 42

A lesion to what part of the cerebral cortex would cause Contralateral Paralysis?

Back 42

Primary Motor Cortex

Front 43

A lesion to what part of the cerebral cortex would cause Contralateral Loss of Somatic Sensation?

Back 43

Primary Sensory Cortex

Front 44

A lesion to what part of the cerebral cortex would cause Contralateral Hemianopia

Back 44

Primary Visual Cortex

Front 45

A lesion to what part of the cerebral cortex would cause Astereognosis (inability to identify an object by touch without visual input)?

Back 45

Supramarginal Gyrus (area 40)

Front 46

A lesion to what part of the cerebral cortex would cause Alexia (inability to read) and Agraphia (inability to write)?

Back 46

Lesion of the Angular gyrus (area 39)

Front 47

A lesion to what part of the cerebral cortex would cause motor aphasia?

Back 47

Lesion to Broca's area on L side (area 44 and 45)