The First and Second Cranial Nerves

Question 1

What are the Cranial Nerves?

Answer 1

I - Olfactory Nerve
II - Optic Nerve
III - Occulomotor Nerve
IV - Trochlear Nerve
V - Trigeminal Nerve
VI - Abducens Nerve
VII - Facial Nerve
VIII - Vestibulocochlear Nerve
IX - Glossopharyngeal Nerve
X - Vagus
XI - Accessory Nerve
XII - Hypoglossal Nerve

Question 2

Cranial Nerve I
Function of the Olfactory Nerve

Answer 2

Smell/Olfaction

Question 3

Cranial Nerve I
Components of the Olfactory System

Answer 3

Olfactory Epithelium
Olfactory Nerve
Olfactory Bulbs
Olfactory Tracts
Olfactory Cortex/Rhinencephalon

Question 4

Cranial Nerve I: Olfactory Epithelium
Location

Answer 4

Roof
Superior Conchae
Upper Part of Nasal Septum

Question 5

Cranial Nerve I: Olfactory Epithelium
Cell Type

Answer 5

Bipolar Nerve Cells

Question 6

Cranial Nerve I: Olfactory Epithelium
Peripheral Process

Answer 6

Terminate in olfactory hairs

Question 7

Cranial Nerve I: Olfactory Epithelium
Central Processes forms the …

Answer 7

olfactory nerve

Question 8

Cranial Nerve I: Olfactory Nerve
Course

Answer 8

Olfactory Nerves pass through Cribiform Plate and synapse with cells of Olfactory Bulb

Question 9

Cranial Nerve I: Olfactory Bulb
Description

Answer 9

Oval mass of Gray Matter which overlies the Olfactory Sulcus

Question 10

Cranial Nerve I: Olfactory Tract
Formation

Answer 10

Axons of cells in Olfactory Bulb form Olfactory Tract

Question 11

Cranial Nerve I: Olfactory Tract
Description

Answer 11

Narrow-elongated band that overlies Olfactory Sulcus

Question 12

Cranial Nerve I: Olfactory Tract
Divisions

Answer 12

Lateral and Medial Striae

Question 13

Cranial Nerve I: Olfactory Tract
The Striae connect the ____ to the ____

Answer 13

__Olfactory Tract__
__Primary and Secondary Olfactory Areas of Cortex__

Question 14

Cranial Nerve I: Olfactory Cortex
Divisions

Answer 14

Primary
Secondary

Question 15

Cranial Nerve I: Olfactory Cortex
Primary Division Formation

Answer 15

Anterior Perforated Substance
Piriform Cortex (in Uncus)
Amygdala (in Uncus)

Question 16

Cranial Nerve I: Olfactory Cortex
Primary Division Function

Answer 16

Detects odor

Question 17

Cranial Nerve I: Olfactory Cortex
Secondary Division Formation

Answer 17

Entorhinal Area (Area 28): Anterior Parahipppocampal Gyrus

Question 18

Cranial Nerve I: Olfactory Cortex
Secondary Division Function

Answer 18

Identifies and Correlates odor to past experiences

Question 19

Cranial Nerve II
What are the Pathways of the Optic Nerve?

Answer 19

Visual Pathway
Light Reflex Pathway
Accommodation Reflex Pathway

Question 20

Cranial Nerve II: Visual Pathway
Overview of Visual Pathway

Answer 20

Question 21

Cranial Nerve II: Visual Pathway
Where do Rods and Cones transmit their signals?

Answer 21

Retinal Ganglion Cells

Question 22

Cranial Nerve II: Visual Pathway
Axon of the Ganglion Cell forms …

Answer 22

Optic Nerve

Question 23

Cranial Nerve II: Visual Pathway
How does the Optic Nerve enter the Skull?

Answer 23

Via Optic Foramen

Question 24

Cranial Nerve II: Visual Pathway
Optic Nerve joins the opposite one to form the …

Answer 24

optic chiasma

Question 25

**Cranial Nerve II: Visual Pathway** Which parts of the retina perceive the head of the arrow?

Answer 25

Right Nasal Retina Left Temporal Retina

Question 26

**Cranial Nerve II: Visual Pathway** Which tract do the fibers perceiving the head of the arrow run in?

Answer 26

Left Optic Tract

Question 27

**Cranial Nerve II: Visual Pathway** Which parts of the retina perceive the tail of the arrow?

Answer 27

Left Nasal Retina Right Temporal Retina

Question 28

**Cranial Nerve II: Visual Pathway** Which tract do the fibers perceiving the tail of the arrow run in?

Answer 28

Right Optic Tract

Question 29

**Cranial Nerve II: Visual Pathway** Which nerves cross in the chiasma?

Answer 29

Fibers from the nasal half of each retina

Question 30

**Cranial Nerve II: Visual Pathway** Nerve fibers of Optic Tract synapse with ...

Answer 30

Lateral Geniculate Body

Question 31

**Cranial Nerve II: Visual Pathway** What are fibers from the LGB to the Visual Cortex called?

Answer 31

Optic Radiation

Question 32

**Cranial Nerve II: Visual Pathway** Which part of internal capsule does the optic radiation pass through? ## Footnote The Internal Capsule is a pathway for the transmission of nerves to and from the Cerebral Cortex

Answer 32

Retrolentiform Part

Question 33

**Cranial Nerve II: Visual Pathway** Splitting of Optic Radiation

Answer 33

Upper Half pass through Parietal Lobe Lower Half pass through Temporal Lobe (Meyer's Loop)

Question 34

**Cranial Nerve II: Visual Pathway** Superior Visual Field Pathway

Answer 34

Superior Visual Field → Inferior Part of Retina → Inferior Part of LGB → Inferior Part of Optic Radiation (Below Calcarine Sulcus)

Question 35

**Cranial Nerve II: Visual Pathway** Inferior Visual Field Pathway

Answer 35

Inferior Visual Field → Superior Part of Retina → Superior Part of LGB → Superior Part of Optic Radiation (Above Calcarine Sulcus)

Question 36

**Cranial Nerve II: Visual Pathway** Function of Primary Visual Area (Area 17)

Answer 36

Interpretation colour, size, shape, motion, illumination

Question 37

**Cranial Nerve II: Visual Pathway** Function of Secondary Visual Area (18, 19)

Answer 37

Object Identification Integration of Perception with Past Experience

Question 38

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 38

1

Question 39

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 39

2

Question 40

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 40

3

Question 41

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 41

4

Question 42

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 42

5

Question 43

**Cranial Nerve II: Visual Pathway** Location of Damage

Answer 43

6

Question 44

What is the Light Reflex?

Answer 44

Optic Nerve (Afferent) detects light Oculomotor Nerve (Efferent) constricts both eye pupils

Question 45

**Cranial Nerve II: Light Reflex Pathway** Pathway names

Answer 45

**Direct Light Reflex**: Pupil reflex is ipsilateral **Consensual Light Reflex**: Pupil reflex is contralateral

Question 46

**Cranial Nerve II: Light Reflex Pathway** Direct Light Reflex

Answer 46

Light on One Retina → Optic Nerve → Optic Chiasma → Optic Tract → LGB → Pretectal Nucleus → EW nucleus → 3rd nerve → Ciliary Ganglion → Constrictor Pupillae

Question 47

**Cranial Nerve II: Light Reflex Pathway** Consensual Light Reflex

Answer 47

Light causes constriction of both pupils because Pretectal Nucleus is connected to both EW nuclei

Question 48

**Cranial Nerve II: Accommodation Reflex** Adjustments of Accommodation Reflex

Answer 48

Convergence of both eyes Constriction of Pupil Increased Refractive Power of Lens

Question 49

**Cranial Nerve II: Accommodation Reflex** Eye convergence caused by ...

Answer 49

contraction of medial recti

Question 50

**Cranial Nerve II: Accommodation Reflex** Constriction of Pupils caused by ...

Answer 50

contraction of constrictor pupillae

Question 51

**Cranial Nerve II: Accommodation Reflex** Increased Refractive Power caused by ...

Answer 51

contraction of ciliary muscle

Question 52

**Cranial Nerve II: Accommodation Reflex** Pathway

Answer 52

Retina Stimulation → Optic Nerve → Optic Chiasma → Optic Tract → LGB → Optic Radiation → Visual Cortex → Superior Longitudinal Bundle → Frontal Eye Field (Area 8) → EW nucleus → Oculomotor Nerve → Cilliary Ganglion → Sphincter Pupillae Muscle of Ciliary Muscle