lecture 15 vision Flashcards
1
Q
vision journey
A
eye optic nerve cross over at optic chiasm lateral geniculate nucleus primary visual cortex
2
Q
where the light goes in the left visual field of both eyes
A
right side
3
Q
three main layers of the eye
A
fibrous
vascular
neural
4
Q
outer most layer of the eye
A
fibrous layer
5
Q
what is the fibrous layer made up of
A
cornea and sclera
6
Q
vascular layer
A
choriod
ciliary body
iris
7
Q
choriod
A
network of blood vessels
8
Q
ciliary body
A
musclucal layer which controls the shape of the lens
9
Q
neural layer
A
retina
10
Q
anterior chamber is behind
A
cornea
11
Q
posterior chamber behind the
A
lens
12
Q
posterior chamber filled with
A
vitreous humour
13
Q
anterior chamber filled with
A
aqueous humour
14
Q
two types of eye movement
A
gaze stabalisation
gaze shifting
15
Q
which type of eye movement do we have more voluntary control over
A
gaze shifting
16
Q
gaze stabalisation eye movements
A
vestibulo ocular and optokinetic
17
Q
vestibular ocular eye movements used when
A
rapid head movement
18
Q
optokinetic eye movement used when
A
slow head movement
19
Q
gaze shifting eye movements
A
saccade, smooth pursuit and vergence
20
Q
what is saccade
A
directing the eyes to a target
21
Q
what is smooth pursuit
A
directing the eyes to a moving target
22
Q
what is vergence
A
adjusting the eyes to different distances
23
Q
conjugate eye movements
A
eyes move in the same direction
24
Q
disconjugate
A
eyes move in opposite directions
25
e.g of conjugate eye movements
vestibulor ocular, optokinetic, saccade and smooth pursuit
26
e.g. of disconjugate eye movements
vergence
27
extra occular muscles
superior oblique, inferior oblique, superior rectus, medial rectus, lateral rectis and inferior rectus
28
eyelid msucle
levator palpebrae superioris
29
adduction
medial rectus
30
abduction
lateral rectus
31
eye elevators
superior rectus
| inferior oblique
32
eye depressors
inferior rectus
| superior oblique
33
cyclic rotations of the eye
intorsion
| extorsion
34
intorsion muscles
superior rectus
| superior oblique
35
extorsion muscles
inferior rectus
| inferiro oblique
36
what three nerves innervate the extraocular muscles
oculomotor, trochlear and abducens
37
occulomotor innervates the
medial rectus, superior rectus and inferior oblique
38
what cranial nerve is the occularmotor
3
39
trochlear innervates
superior oblique
40
what CN is trochlear
4
41
what innervates lateral rectus
abducens
42
what cranial nerve is abducens
6
43
where are the nuclei of 3, 4 and 6 CN
brainstem
44
what part of the brain controls eye movements
frontal eyefield of the motor cortex
45
planning eye movements in the brain
supplementary eye field
46
what does the superior coliculus do
orientating an object in your visual field
47
area with the highest number of nerve endings, why?
cornea
| protection
48
most metabolicaly active part of the body, why?
cornea
| repair itself
49
what attatches the ciliary body to the lens
zonules
50
what are zonules
connecting fibres
51
what does the ciliary body do
contains muscles which can change the shape of the lens
52
what changes the pupil size
muscles of the iris
53
aniscoria
pupils have different sizes
54
miosis
pupil constriction
55
what is active in miosis
iris sphincter
56
miosis in response to
light increase
57
miosis control
parasympathetic
58
mydriasis
pupil dilation
59
mydriasis active
iris dilator
60
mydriasisin reponse to
less light
61
mydriasis control
sympathetic
62
accomodation
focusing an image with the lens
63
lens looking in the distance
flat
64
lens looking at something near
curved
65
direction of eyes looking in the distance
diverge
66
direction of eyes looking near
converege
67
looking at near objects control
parasympathetic
68
nucleus involved in accomodation
edinger westphal nucleus
69
where would you find edinger westphal nucleus
brain stem
70
most common cause of blindness globally
cateracts
71
what are cateracts not a problem
easily treated
72
what are cateracts
opacification of the lens
73
what are cateracts caused by
compacting and protein deposition
74
cateracts risk factors:
trauma, aging, diabetes, smoking, radiation, genetics
75
alot of time spent where will accelerate the cateract process
in the sun
76
how are cateracts treated
surgicaly artifiscial lens
77
anterior chamber is filled with
aqueous humour
78
what produces aqueous humour
ciliary processes
79
how is the aqueous humour drained from the anterior chamber
trabecular meshwork
80
what drains the aqueous humour out of the eye
schlemms canal
81
glaucoma
increased intraocular pressure
82
glaucome risk factors
high blood pressure
long term corticosteroid use
severe myopia
eye injury
83
most common type of glaucoma
primary open angle glaucoma
84
onset of POAG
slow
85
POAG caused by
trabecular meshwork being clogged
86
acute angle closure glaucoma
rapid onset
emergency
nausea
vomitting
87
how can you detect glaucoma
look into the eye for optic nerve damage
88
how to measure intraocular pressure
tonometer
89
glaucoma treatment: beta blocker
blocks aqueous humour inflow
90
glaucoma treatment: alpha 2 adrenoceptor agonists
blocks aqueous humour inflow
91
glaucoma treatment: muscarinic agonists
increase trabecular outflow
92
glaucoma treatment: prostoglandin agonist
increase aqueous humour outflow
93
outer retina blood supply
choriod
| choriocapillaris
94
inner retina blood supply
retina vasculature
95
part of the eye with no vasculature
fovea
96
how does the retinal vasculature get to the eye
optic nerve
97
where are the light sensative cells
outside layer at the back
98
outermost layer of cell in the eye
retinal pigment layer
99
what are the two types of light sensitive cells
rod and cone
100
middle layer of cells
bipolar
horizontal
amacrine
101
purpose of bipolar cells
pass information from the light sensitive cells to the ganglion cells
102
purpose of amacrine and horizontal cells
horizontal communication
103
inner most layer of cells
glanglion
104
very center of the retina light sensitive cells
only cones
105
spreading our from the center of the retina what is the distribution of light sensitive cells
rods incresa, cones decrease
| they both get fatter
106
what type of vision are rods sensative to
scotopic - night
107
what type of vision are cones sensitive to
phototopic
108
how many types of cone are there and what are they for
3 for colour
109
red green colour blind inheritance
recessive X chromosome
110
what are dichromats
only have two types of cone
111
protanopes
lack red L cones
112
deutranopes
lack green M cones
113
tritanopes
lack blue S cones
114
Anomalous trichromats
one cone type is less sensitive
115
how many layers does the lateral geniculate nucleus have
6
116
bottom two layers of the LGN
magnocellular
117
magnocellular size
large
118
magnocellular recieve input from
A ganglion
119
type of input magnocellular recieve
light and dark
120
top 4 layers of the LGN
parvocellular
121
parvocellular cell size
small
122
parvocellular recieve input from
B ganglion cells
123
where does info go after LGN
PVC
124
how does infro go from LGN to PVC
optic radiations
125
center of the visual field is processed
at the back of the brain
126
V4
colour
127
V5
motion
128
Parahippocampal place area
scenes
129
Fusiform face area
faces
130
lesion to Fusiform face area
prosopagnosia
131
prosopagnosia
cant recognise faces
132
Lateral occipital cortex
objects
133
Optic ataxia
cat orientate hands to do something
134
Visual form agnosia
cant recognise objects
