DLA 26 +27 + Lecture 25+26

Question 1

horner’s syndrome

Answer 1

loss of sympathetic innervation

symptoms:
miosis
ptosis
anhidrosis

Question 2

myopia correction

Answer 2

nearsightedness; image focused before retina

correct with concave lens

Question 3

hyperopia correction

Answer 3

farsightedness; image focused behind retina

correct with concave lens

Question 4

Dyschromatopsia

Answer 4

red-green color blindness

rare in women; mostly seen in men

Question 5

protanopia

Answer 5

defective long-wavelength cones (L-cones)

results in varying degree of color blindness

hard to determine difference between blue and green and red and green

Question 6

Deuteranopia

Answer 6

medium-wavelength (green) cones are missing

dichromat (no green cones at all) 
anomalous trichromat (defective green cones) 

most common
red and green are hardest to detect

Question 7

papilledema

Answer 7

swelling of the optic disk
almost always bilateral
due to increased intracranial pressure

short issues with vision, headache, vomiting

optic disk will be white and elevated; not normal yellow

associated with: 
tumors in brainstem and cerebellum 
hematoma 
cerebral edema (TBI) 
increased CSF

Question 8

Diabetic retinopathy

Answer 8

chronically high blood sugar levels from diabetes is damaging to the small retinal blood vessels

early stage:
micro-aneurysms
weakness in the walls of vessels; will leak fluid

late stage:
proliferation of new vessels
scar tissue
floaters

will be seen in both eyes usually
treatment aimed at slowing or stopping progression

Question 9

Age-related macular degeneration (AMD)

Answer 9

macula:
area of the retina dedicated to central vision
no large blood vessels

leading cause of vision loss
blurred vision in central field
affects one or both eyes over time

no effective treatment

Risk factors include age, smoking, stroke or coronary heart disease, obesity, family history

Question 10

where in the visual field is the blind spot

Answer 10

blind spot is in the temporal visual hemifield since optic disk is in nasal hemiretina

Question 11

what part of the brain is required for vision experience

Answer 11

lateral geniculate nucleus (thalamus)

others (projections, not needed for experience)

hypothalamus - suprachiasmatic nucleus
mid brain - pretectal nucleus
mid brain - superior colliculus

Question 12

what area is the primary visual cortex

Answer 12

area 17

Question 13

what pathway involves color

Answer 13

ventral (inferior temporal) pathway

Question 14

Cerebral Achromatopsia

Answer 14

a type of color blindness that is due to damage to the cerebral cortex

Question 15

Cerebral Hemiachromatopsia

Answer 15

a type of color blindness that affects one half of the visual field due to cerebral damage

Question 16

Visual word form area (VWFA)

Answer 16

specialized for visual word processing

located in the ventral occipitotemporal cortex (left bias)

Question 17

letter form area

Answer 17

area that is used for letter processing

located in the left OTC posterior to the VWFA

Question 18

lesion of the VWFA

Answer 18

lesion leads to alexia

selective impairment in reading with other language functions in tact

Question 19

Fusiform face area (FFA)

Answer 19

ventral occipitotemporal cortex (OTC) but has a right bias

role in face recognition and perception

Question 20

lesion to the FFA

Answer 20

lead to prosopagnosia.. the inability to identify faces visually

Question 21

Akinetopsia

Answer 21

conscious loss of visual motion perception

can be traumatic, vascular, degenerative

human visual motion area occupies the lateral cortex at the occipital/parietal/temporal junction

Question 22

optic nerve lesion

Answer 22

monocular blindness

could be due to optic neuritis

Question 23

optic chiasm lesion

Answer 23

Bitemporal hemianopia (one half visual field lost both eyes)

may be due to pituitary tumor

Question 24

optic tract lesion

Answer 24

Homonymous hemianopia (only see on side of visual field)

may be due to temporal lobe tumor

Question 25

Temporal radiation (Meyer-Archambault loop)

Answer 25

Homonymous superior quadrantanopia (loss of vision in upper 1/4

may be due to temporal lobe tumor

Question 26

Parietal radiation

Answer 26

Homonymous inferior quadrantanopia (loss of vision in lower 1/4)

may be due to parietal lobe tumor

Question 27

primary visual cortex lesion

Answer 27

Homonymous hemianopia (person will only see one side of visual field)

could be due to PCA infraction