D3- Physiological Optics & Binocular Vision Flashcards
1
Q
Science that deals with the normal functions of living organism and their parts
A
Physiology
2
Q
Study of sight and behavior of light
A
Optics
3
Q
Visual science that deals with the study of structures of the eye and functions affected by behavior of light
A
Physiological Optics
4
Q
Has the power to adjust to environmental changes
A
Animate
5
Q
Stimulus not capable of responding
A
Inanimate
6
Q
Something that causes physiological/psychological response
A
Stimulus
7
Q
Receives the environmental stimuli
A
Receptor
8
Q
A bodily organ which becomes active in response to stimulation
A
Effector
9
Q
Strands of protoplasm which connects the two organs (receptor and effector)
A
Neurons
10
Q
Refers to the refractive power of the lens
A
Dioptrics
11
Q
Unit for measuring the dioptric power of the eye
A
Diopter
12
Q
Ratio of speed of light in air to speed of light in other optical medium
A
Index of Refraction
13
Q
Length of the eyeball
A
24 mm
14
Q
Weight of an eyeball
A
10g
15
Q
Volume of an eyeball
A
6.5 mL
16
Q
3 coats/tunics of the eyeball
A
Fibrous coat
Uveal coat
Nervous coat
17
Q
Fibrous coat comprises:
A
Sclera
Cornea
Limbus
18
Q
White of the eyeball
A
Sclera
19
Q
Hard and tough layer of the eye
A
Sclera
20
Q
Main refractive apparatus of the eye
A
Cornea
21
Q
By its transparency, permits light reach interior of the eye
A
Cornea
22
Q
Transition zone between sclera and cornea
A
Limbus
23
Q
Uveal coat comprises of:
A
Choroid
Ciliary body
Iris
24
Q
Thin, dark membrane of the eye
A
Choroid
25
Nourishes the outer part of the retina
Choroid
26
Prolongation and thickening of the choroid
Ciliary body
27
Nourishes the cornea and lens through aqueous humor
Ciliary body
28
Serves as attachment of the zonular fibers
Ciliary body
29
Has pigmentation that gives color
Iris
30
Regulate the light entering the eye
Iris
31
Reduces chromatic and spherical abberations
Iris
32
Nervous coat comprises of:
Retina
33
Thin, transparent membrane upon which the images are cast and in where nerve impulses are generated
Retina
34
Mathematical or physical model that represents the basic optical features of the real eye
Schematic eye
35
Index of refraction of the CORNEA
1.376
36
Index of refraction of AQUEOUS HUMOR
1.336
37
2/3 of refraction of the eye
Cornea
38
Where cornea owes its clear optical surface
Tear Layer
39
Steeper curvature will result to?
Higher surface power
40
Flatter curvature will result to?
Lower surface power
41
1/3 refraction of the eye, important structure for ACCOMMODATION
Crystalline lens
42
Process which crystalline lens varies its focal length in response to changes in vergence
ACCOMMODATION
43
Dioptric adjustment of the eye to attain maximum sharpness of retinal imagery
ACCOMMODATION
44
If the accommodation is insufficient, object will fall in the?
Behind the retina
45
If the accommodation is insufficient, this is termed as?
Lag of accommodation
46
If the accommodation exceeds it is termed as?
Lead of accommodation
47
The relationship between posterior principal focus, refractive mechanism, and retina of the same eye with accomm relaxed
REFRACTIVE STATUS
48
Focal points of the refracting mechanisms
Posterior principal focus
49
Refractive medias
Cornea
Crystalline lens
Aqueous humor
Vitreous humor
50
Factors that influence refractive status:
Length of the eyeball
Power of cornea
Power of lens
Depth of anterior chamber
51
Posterior principal point is focused on the retina
Emmetropia
52
Posterior principal point focused in front or behind the retina
Ametropia
53
Process of seeing:
Physical process
Photo-chemical process
Neuro-muscular process
Psychological process
54
Process wherein an incident ray of light strikes the eye and its transmission through the various transparent media
Physical process
55
The transformation of a radiant energy at the neuro-epithelium into some other form of energy
Photochemical process
56
The generation of the nerve impulse in the retina and its transmission by a chain of neuron to the central nervous system
Neuro-muscular process
57
The interpretation of the stimulus received by the retina
Psychological process
58
A transparent membrane where images are cast and where nerve impulses are generated and converted to the optic nerve
Retina
59
Nerve of sight
Optic nerve
60
Posterior continuation of optic chiasma with its fibers terminating at lateral geniculate body
Optic tract
61
Serves as the end station for some visual fibers
Lateral geniculate body
62
Carry visual impulse to area striata
Optic radiation
63
Visual/optic center of the brain located at medial aspect of the occipital lobe
Area striata
64
Complete inability of the eye to see
Blindness
65
One eye is completely blind
Uniocular blindness
66
Half blindness
Hemianopsia/hemianopia
67
Loss of either peripheral or central vision
Heteronymous hemianopsia
68
Both eyes are blind to either right or left side
Homonymous hemianopsia
69
Hemianopsia on both eyes are completely symmetrical in extent and intensity. Same size, shape, and position. Damage closer to the brain
Congrous hemianopsia
70
Visual field defects are dissimilar in both eyes. Damage farther to the brain
Incongrous hemianopsia
71
Scotoma wherein perception of light is entirely lost
Absolute scotoma
72
Scotoma wherein perception of light is only diminished
Relative scotoma
73
Scotoma that appears as black spot on the visual field. Patient is not aware.
Negative scotoma
74
Scotoma that appears as a dark spot in the visual field
Positive scotoma
75
Scotoma that involves the point of fixation
Central scotoma
76
Scotoma that involves the peripheral areas
Peripheral scotoma
77
Scotoma that appears usually in person with migraine
Scintillating scotoma
78
Scotoma that is an arch-like and an extension of blind spot. It is a symptom of early stages of glaucoma
Arcuate scotoma
79
Reflex that controls/regulates the intensity of light entering the eye
Pupillary light reflex
80
Greater intensity of light means the pupil is ______
Small
81
Lower intensity of light means the pupil is _____
Large
82
Smaller pupil means _____ light in
Less
83
Larger pupil means ______ light in
More
84
Stimulation of one retina by light produces a contraction of pupil on the same eye
Direct light reflex
85
Stimulation of one retina by light produces a contraction of pupil on the opposite eye
Consensual light reflex
86
Person looking at an object close to the face will cause contraction of the pupils
Accommodative convergence reflex
87
Nerve that is responsible for the afferent limb of pupillary reflex
Optic nerve
88
Nerve that is responsible for the efferent limb of the pupillary reflex
Oculomotor nerve
89
Lesion is from retina to nucleus
Relative afferent pupillary defect
90
Lesion is from pre-ganglionic to post ganglionic fiber
Relative efferent pupillary defect
91
Covers the fundamental knowledge based on scientific principles of light and its effect to the eye
Visual optics
92
Real sense organs of the body
Receptors
93
Nerves that connects the receptors to the effectors
Physiological connectors
94
Connects the receptors to the CNS
Sensory
95
Connects the CNS to the responding effectors
Motor
96
What are the visual pathways
Retina
Optic nerve
Optic chiasm
Optic tract
Lateral geniculate body
Optic radiation
Visual cortex
97
The retina consists of two parts
Retinal pigment epithelium
Neural retina
98
Dark pigments in the retina that absorbs light passing through the receptor layer
RPE
99
The neural retina contains five types of neurons
Visual receptor cells
Horizontal cells
Bipolar cells
Amacrine cells
Retinal ganglion cells
100
Part of the retina where image of the central visual field center is focused
Fovea
101
Part of the eye that is formed by the retinal ganglion cell axons that are exiting the retina
Optic disc
102
Pigments that is responsible for photopic vision
Cones
103
Pigments that is responsible for scotopic vision
Rods
104
Two locations in the retina that have no rods
Fovea and optic disc
105
Total number of cones in the retina
4% in the fovea, 96% in the periphery
106
Three different kinds of cones
S, M and L cones
107
Photopigment of S cone
Cyanolabe
108
Photopigment of M cone
Chlorolabe
109
Photopigment of L cone
Erythrolabe
110
The ability to detect and recognize small objects visually
Visual acuity
111
Field of vision that operates best under high illumination
Central vision
112
Field of vision that has the greatest visual acuity and color sensitivity
Central vision
113
Field of vision that is more sensitive to dim light
Peripheral vision
114
Field of vision that operates under low illumination
Peripheral vision
115
A small ________ is located in the temporal hemifield
Blindspot
116
Image formed by the optical system of the eye
Optical image
117
Image formed on the retina which may be either sharply focused or blur circle
Retinal image
118
The farther the optical image from the retina, the _______ the blur cirle
Bigger
119
The smaller the pupil, the ________ the blur circle
Smaller
120
The extent to which the image may be located in front or behind the retina and still appear to be clear
Depth of focus
121
The extent to which the object may be moved toward or away and yet remain clear with the same dioptric power
Depth of field
122
The ability to detect differences in the wavelength of light
Color vision
123
Color vision may be tested using:
Ishihara test plates
Farnsworth D-15
Anomaloscope
Lanterns
124
Having a sense of direction while moving around an environment
Spatial orientation
125
The process of producing a single image from the two disparate monocular images
Binocular fusion
126
The ability to perceive the distance of an object
Depth perception
127
If two objects are roughly the same size, the object that looks the largest will be judged as being closest to the observer
Relative size
128
As you are moving, objects that are closer seem to zoom by faster than do objects in the distance
Motion parallax
129
Objects that are farther away seem to be blurred or slightly hazy
Aerial perspective
130
Parallel lines appear to meet as they travel into the distance
Linear perspective
131
When one object overlaps another, the object is partially obscured is perceived as being farther away
Overlap
132
What are the refractive errors of the eye
Myopia
Hyperopia
Astigmatism
133
An inherited disorder in which there is a gradual and progressive failure to maintain receptor cells
Retinitis Pigmentosa
134
A symptom of this condition is night blindness and loss of peripheral vision
Retinitis Pigmentosa
135
A vitamin deficiency that can cause permanent blindness
Vitamin A deficiency
136
The leading cause of blindness in the elderly
Macular Degeneration
137
A form of macular degeneration which involves intraocular proliferation of cells in the macular area, fovea, and surrounding retinal areas
Dry ARMD
138
A form of macular degeneration where capillaries of the choroid invade the macular area
Wet ARMD
139
A condition where the neural retina is torn away from the RPE
Retinal detachment
140
A condition which involves microaneurysm and punctate hemorrhages in the retina
Diabetic retinopathy
141
What are the vitreoretinal sources of entoptic images?
Moore's lightning streaks
Purkinje Figures
142
Entoptic images consisting of flashes of light on the visual field and is associated with stress
Moore's lightning streaks
143
Appearance of tiny bright dots moving rapidly along squiggly lines in the visual field
Blue field phenomenon
144
A phenomenon caused by white blood cells moving in the capillaries in front of the retina
Blue field phenomenon
145
Is the perception of light without light actually entering the eye
Phosphene
146
Refers to an image continuing to appear in one's vision after the exposure to the original image has cased
Afterimage
147
Aspect of things that is caused by differing qualities of the light reflected or emitted by an object
Colors
148
Sometimes called Chromatics or colorimetry
Science of color
149
It includes the perception of color by the human eye and brain
Chromatics
150
A color that is evoked by a single wavelength of light in the visible spectrum
Spectral color
151
A process that allows the brain to recognize a familiar object as being a consistent color
Color constancy
152
Theory that suggests that both the eye and brain are involve in color constancy
Retinex theory
153
Who discovered the retinex theory?
Edwin H. Land
154
He discovered the trichromat theory
Thomas Young
155
He discovered the opponent theory of colors
Ewald Hering
156
Theory that suggests that the ability of the human eye is to distinguish colors based upon the varying sensitivity of photoreceptors in the retina
Trichromat theory
157
A region of luminance levels and color temperatures that are often viewed as comfortable or pleasing to an observer
Kruithof Curve
158
The ability to distinguish objects based on the wavelengths and frequencies of the light they reflect
Color vision
159
The ability to discriminate light on the basis of wavelength composition
Color vision
160
How many rods are in the eye
120 million
161
Where are rods located?
Peripheral retina
162
Rods has photopigment called
Rhodopsin
163
How many cones are in the eye
6-7 millions
164
Where are cones located?
Central retina
165
Cones has photosensitive protein called
Photopsin
166
The most common color vision deficiency
Deuteranomaly or Anomalous deuteranopsia
167
Color vision deficiency where the green-sensitive cones have decreased sensitivity
Deuteranomaly or Anomalous deuteranopsia
168
Referred to as "red weakness"
Protanomaly or Anomalous protanopia
169
A rare type of anomalous trichromatic vision
Tritanomaly
170
Color vision deficiency where the blue-sensitive cones have decreased sensitivity
Tritanomaly
171
A color vision deficiency where one of the three groups of cone cells is missing or not functioning
Dichromacy
172
The most common type of dichromacy
Protanopia
173
A type of dichromacy where the px is unable to spot red color and have difficulty spotting green color
Protanopia
174
A type of dichromacy where it does not have green cone cells making him or her unable to spot green color
Deuteranopia
175
The most rarest form of dichromacy having a ratio of 10 in 1 million people
Tritanopia
176
In this type of dichromacy, the patient is unable to distinguish between yellow and blue
Tritanopia
177
Reduced or complete loss of color discrimination
Achromatopsia
178
Refers to the complete loss of color vision
Rod monochromatism
179
Refers to incomplete loss of color vision
Cone monochromatism
180
Perceive everything just in shades of gray
Monochromacy/Achromatopsia
181
Most commonly referred to as total color blindness
Monochromacy (Achromatopsia)
182
Test used for red-green color deficiencies
Ishihara color test
183
Ishihara color test is named after?
Dr. Shinobu Ishihara
184
Color vision test that consists of a number of colored plates each of which contains a circle of dots appearing randomized in color and size
Ishihara color test
185
Refers to a plate in Ishihara where individuals with color defect should see a different figure from individuals with normal color vision
Transformation plates
186
Refers to a plate in ishihara where only individuals with normal color vision could recognize the figure
Vanishing plates
187
Refers to a plate in Ishihara where only individuals with color vision defect could recognize the figure
Hidden digit plate
188
Color vision test that can be used to classify all three different forms or color vision deficiency
Hardy-Rand-Rittler
189
Intended to classify color vision defects by using a set of discs
D-15
190
This is accomplished by the arrangement of unsaturated colored discs
Lanthony desaturated d-15
191
Provides the most accurate way to test the severity of color blindness
Anomalosocpe
192
Coordinate use of BOTH eyes to produce single mental image
Binocular vision
193
Blending of sight to form single percept
Fusion
194
Proper coordination of eyes and brain
Neuroplasticity
195
Pre-requisites for single binocular vision
Frontally placed eyes, overlapping retinal fields
Partial decussation of the optic nerve fibers
Foveal region stimulated
Corresponding or identical points
Size of retinal images
Efficient functions of EOM and nerves
196
Equal size of retinal images
Iseikonia
197
Unequal size of retinal images
Aniseikonia
198
Equal best corrected VA
Iso-oxypia
199
Unequal best corrected VA
Aniso-oxyopia
200
High difference of refractive error
Anisometropia
201
Different refractive statuses
Antimetropia
202
Advantages of binocular vision
Single vision
Optical defects in one eye are made less obvious by the normal image of the other eye
Enlarged field of vision
Power to discriminate details and contours of an object is better with two eyes than one eye alone
Loss of one eye will seriously handicap the individual
Stereopsis
Compensation of blindspot and other differences
203
At what month the eyes are normally hyperopic
At birth
204
At what month the eyes follow light
In newborn
205
At what month the eyes follow large objects
At 2 months
206
At what month foveas are fully formed
At 3 months
207
At what month they hold objects
At 3 months
208
At what month eyes are expected to be straight
At 3-4 months
209
At what month they fixate an object for 1-2 min.
At 6 months
210
At what age the VA is at 20/70
1 year old
211
At what year does fusional mechanism becomes fully developed?
1-1 1/2 year old
212
At what age does accommodation develops with sharpening VA
at 3 years old
213
At what age is the age of emmetropization
7-12 years old
214
Binocular-like instrument that makes use of a SEPTUM to separate images
Stereoscope
215
The images used (plates) in stereoscope is called?
Stereogram
216
Light passing through a prism is bent towards the
BASE
217
Eyes looking through a prism is displaced on the
APEX
218
Object viewed through a prism is displaced on the
APEX
219
9 positions of gaze
Ortho
Dextroversion
Levoversion
Supraversion
Infraversion
Dextrosupraversion
Dextroinfraversion
Levosupraversion
Levoinfraversion
220
Movement of one eye only
Duction
221
Movement of one eye inwards
Adduction
222
Movement of one eye upwards
Supraduction
223
Movement of one eye downwards
Infraduction
224
Movement of the vertical corneal meridian of one eye outward
Exycloduction
225
Movement of the vertical corneal meridian of one eye inward
Incycloduction
226
Synchronous and symmetric movement of both eyes in same direction
Version
227
Synchronous and symmetric movement of both eyes in opposite direction
Vergence
228
Strongest, heaviest, broadest muscle
Medial rectus
229
Muscle that has the closest insertion from limbus
MR
230
Muscle that is innervated by CN #6
LR
231
Muscle that has no secondary and tertiary actions
LR
232
Muscle that has the farthest insertion from the limbus
SR
233
The retina is derived from ______
Neural tube
234
This region of the retina is devoid of receptor cells
Optic disc
235
Photopigment that is more sensitive to light and react at lower light levels
Rhodopsin
236
Photopigments that are less sensitive to light and require high illumination levels
Photopsin
237
Defined as an unknown number of women perceiving millions of colors invisible to the rest of us
Tetrachromacy
238
Theory that suggests that there are three opponent channels of colors: red versus green, blue versus yellow, and black versus white
Color Opponent Theory
239
Primary action is horizontal and vertical
Recti muscles
240
Longest muscle
Superior oblique
241
Innervated by CN #4
Superior oblique
242
Points of connections of all recti muscles
Spiral of Tillax
243
Cross diagram that shows which muscle move when the eye moves to a given direction
Benzene Ring
244
“Primary muscle”, muscle that moves the eye to a given direction
Agonist
245
“Opposing muscle”, muscle that opposes the action of the agonist
Antagonist
246
“Helping muscle”, muscle that acts in concert with the agonist to produce a given movement
Synergist
247
Agonist muscle of both eyes
Yoke muscle
248
Law that states that when a nervous impulse is sent to a muscle causing it to contract, an equal impulse goes to the contralateral synergist
Hering’s Law of Equal Innervation
249
Law that states that when a muscle contracts, its direct antagonist relaxes to an equal extent
Sherrington’s Law of Reciprocal Innervation
250
Imaginary line where movements of the eye takes place
Visual Axes
251
Planes of the eye that lies on the optic axis and transverse axis
Horizontal plane
252
Planes of the eye that lies on the optic axis and vertical axis
Median plane
253
Planes of the eye that lies on the transverse axis and vertical axis
Equatorial plane
254
The act or process of directing the eye towards the object of regard
Fixation
255
Image of the real pupil found at the cornea
Entrance pupil
256
Point towards which the observer directs his gaze
Object of regard
257
Point located 13.5 mm behind the cornea
Center of rotation
258
Line drawn from the object of regard to the center of rotation
Line of sight
259
Line from the center of entrance pupil and passes through the center of curvature of the cornea
Pupillary axis
260
An imaginary straight line passing through the midpoint of cornea and retina
Optic axis
261
Angle formed by the intersection of the pupillary axis and the line of sight
Angle lambda
262
Angle formed by the intersection of optic axis and line of sight at the center of rotation
Angle gamma
263
Angle formed by the visual and optic axes at the nodal point
Angle alpha
264
Line connecting the centers of rotation of both eyes
Baseline
265
Plane which includes both the object of regard and baseline
Plane of regard
266
Plane tangent to the chin and the two super-ciliary ridges
Face plane
267
An imaginary eye located between the two physical eye
Cyclopean eye
268
Retinal elements of the two eyes that share a common subjective visual direction
Retinal correspondence
269
A theoretical circle passing through the fixation point and nodal points of two eyes
Horopter
270
Theory of fusion that states that fusion operates upon a psychological and cerebral level
Worth’s theory
271
Theory of fusion that is also known as Theory of Replacement
Verhoeff’s Theory
272
Theory of fusion that maintains that single image is merely a projection of two indentical images to the same perceptual position
Wall’s theory
273
Degree of fusion
1- Simultaneous Perception
2- Fusion
3- Depth Perception
