Olfactory and Visual Systems

Question 1

Bradykinesia (slow movement) would be associated with what disease ?

Answer 1

Parkinsons disease

Question 2

hemiballismus, a dramatic movement disorder would be the result of damage to where in the brain?

Answer 2

subthalamic nucleus

Question 3

Chorea, which causes rapid involuntary movements, is a disorder most commonly associated with what disease ?

Answer 3

Huntingtons disease

Question 4

gait ataxia is most commonly the result of injury to the ______ of the cerebellum

Answer 4

vermis

Question 5

fearless, and placid behavior, known as Kluber-Bucy Syndrome, is the result to injury where ?

Answer 5

amygdala

Question 6

the inability or failure to form new memories would be the result of injury to where in the brain ?

Answer 6

hippocampus

Question 7

hemiparesis and spasticity on one side of the body would occur with an injury to the _______ of the internal capsule

Answer 7

posterior limb

Question 8

dismetria, or the inability to coordinate movements (touch finger to nose tip), would be the result of injury to _____ of the cerebellum

Answer 8

lateral hemisphere

Question 9

what are the 2 main functions of olfaction

Answer 9

taste and smell

Question 10

the origin of the olfactory system that sits in the roof of the nasal cavity is called what ?

Answer 10

olfactory epithelium

Question 11

what does the olofactory epithelium contain

Answer 11

3 million receptor cells

sensory endings for CN V (irritant smells)

Question 12

what is structure of an olfactory receptor and why are the unusual amongst other human nuerons

Answer 12

structure : vesicle w/10-30 cilia emerging out

-unique bc its replaced throughout life as its lifespan is only 1-2 months

Question 13

what are olfactory fila and where do they go ?

Answer 13

• bundles of olfactory axons
• pass through holes in cribiform plate ending in olfactory bulb
• * olfactory fila make up CN I**

Question 14

olfactory bulb develops as an outgrowth of ?

Answer 14

telencephalon

Question 15

what are mitral cells

Answer 15

main projection neuron of olfactory bulb which form olfactory tract

Question 16

what forms the glomerulus in the olfactory bulb

Answer 16

dendrites

Question 17

each olfactory receptor is specific to _______ mitral cell glomerulus

Answer 17

one

Question 18

fibers in the olfactory tract have projections to where ? What 2 are where they generally end ?

Answer 18

• anterior olfactory nucleus
• olfactory tubericle
• Primary Olfactory Cortex (Main end)
• Amygdala (Main end)

Question 19

what two eye structures focus the image on the retina

Answer 19

cornea and lens

Question 20

focusing and image requires what ? which eye structures allow this to happen

Answer 20

refraction

• cornea (70 %)
• lens (30%)

Question 21

what does the iris do ?

Answer 21

affects brightness and quality of image focused on retina

Question 22

the retina has how many nuclear layers ? and how many synapses occur w/in these layers

Answer 22

3 nuclear layers w/ 2 synapse layers

Question 23

what are the 2 photoreceptors in the retina and what is unique to each

Answer 23

Rods - rhodopsin, low acuity and dim light

Cones - high acuity, color, lots of lights

Question 24

what happens to old rod and cone photoreceptor cells as they age

Answer 24

phagocytized by pigment epithelium

Question 25

where is the blind spot in the retina and, how does the brain accomodate for this area

Answer 25

at the optic disk where there are no photoreceptors | -brain automatically fills this space in

Question 26

what is the macula ?

Answer 26

specialization of the retina designed for vision of highest acuity -contains fovea in center

Question 27

what is the fovea

Answer 27

center of macula - area of lots of cones and no rods - area of highest visual acuity

Question 28

what is the thalamic relay nucleus for the optic pathway

Answer 28

lateral geniculate nucleus (LGN)

Question 29

after optic tract fibers end in the LGN, where do they project to

Answer 29

visual cortex in occipital lobe

Question 30

Fibers that represent inferior visual fields are the most _______ radiations, whereas fibers representing superior visual fields are _______________

Answer 30

superior, inferior in radiations

Question 31

what part of the internal capsule is involved with the superior visual field

Answer 31

retrolenticular part

Question 32

what part of the internal capsule has optic radiations pertaining to the inferior visual field

Answer 32

sublenticular part

Question 33

Explain the visual fields, which cross and which remain uncrossed

Answer 33

- fibers of nasal half of retina cross at optic chiasm | - fibers of temporal half remain uncrossed

Question 34

what part of the optic pathway is responsible for depth perception

Answer 34

optic chiasm, allows for comparison of areas via each retina

Question 35

The structure of the LGN is made of _____ layers

Answer 35

6

Question 36

what layers of the LGN are responsible for contralateral eye, which layers are responsible for the ipsilateral eye

Answer 36

1,4,6 contralateral | 2,3,5 ipsilateral

Question 37

what is the parvocellular layer

Answer 37

layers 3-6 of the LGN responsible for color and form

Question 38

what is the magnocellular layer

Answer 38

layers 1-2 of LGN responsible for movement and contrast

Question 39

who was the first to describe the retinotopic organization of the eye using bullet wound injuries

Answer 39

Dr. Tatsuji Inouye

Question 40

in relation to the occipital lobe, the inferior visual field lies above the _______ whereas the superior visual field lies below this

Answer 40

calcarine sulcus

Question 41

where is the macula represented in reference to position on the occipital lobe

Answer 41

most posteriorly, peripheral fields anteriorly

Question 42

what is the line of gennari

Answer 42

striate cortex, or the thin myelin line in primary visual cortex

Question 43

Visual field deficits are named according to what ?

Answer 43

the part of the visual field that is lost

Question 44

# define these terms, - anopia - hemianopia - quadrantanopia - homonymous - heteronymous

Answer 44

- anopia - loss of one or more quadrants - hemianopia - loss of half visual field - quadrantanopia - loss of quarter of visual field - homonymous - same visual field lost in each eye - heteronymous - 2 eyes having non-overalpping field loss

Question 45

damage anterior to the optic chiasm would result in visual field loss for ?

Answer 45

ipsilateral eye

Question 46

damage at the chiasm causes what type of visual field deficits

Answer 46

heteronymous deficit

Question 47

damage to optic tract results in what type of visual field loss

Answer 47

homonymous deficit

Question 48

a lesion in the temporal lobe that interupts Meyers loop would affect what visual field

Answer 48

affect superior visual field cuz meyers loop plays a role in infereior retinal quadrant

Question 49

what is unique about a PCA infarction that results in an eye deficit

Answer 49

the macula is spared in deficit

Question 50

what would happen in the pupillary light reflex if there was a lesion in the occulomotor nerve

Answer 50

- both constrict if shined in unnaffected eye optic nerve | - neither constrict if shine in affected eye optic nerve

Question 51

how would the pupillary light reflex act if ther there was a lesion in the optic radiations

Answer 51

No affect

Question 52

how would a lesion in the visual cortex affect the pupillary light reflex

Answer 52

No effect

Question 53

Besides the LGN to the visual cortex, what are the additional destinations for visual information

Answer 53

- superior colliculus - hypothalamus - superchiasmatic nucleus

Question 54

what is the role of the occipital lobe primary visual cortex in vision

Answer 54

Breaks down visual information and distributes to extrastriate cortex

Question 55

the striate and visual cortex in the occipital lobe have a _______ organization

Answer 55

collumnar

Question 56

each cortical module or collumn controls _____ aspect of the visual field

Answer 56

one

Question 57

what layers of the LGN make up the ventral stream of visual information

Answer 57

Parvocellular layers 3-6 responsible for color and form

Question 58

what layers of the LGN are responsible for the dorsal stream of visual information

Answer 58

Magnocellular layers 1-2 responsible for movement and context