Physiological optics and Binocular Vision Flashcards
1
Q
serve to heighten the protection of the eye from dust and foreign debris, as well as from perspiration.
A
eyelash
2
Q
a cancer that forms IN melanocytes, the cells that produce melanin.
A
•malignant melanoma:
3
Q
- (second degree fusion) is true fusion without stereopsis. It is defined as sensory fusion in which the resultant percept is two-dimensional, that is, occupying a single plane as may induced by viewing a stereogram in which the separation of all homologous points is identical.
A
flat fusion
4
Q
Anterior lens surface radius (relaxed)
A
10 mm
5
Q
•Synapse of axons of visual cells & dendrites of bipolar cells &horizontal cells
A
OUTER MOLECULAR LAYER (OUTER PLEXIFORM LAYER)
6
Q
a delicate web-like structure, this membrane bridges over the grooves and furrows in the surface of the brain
A
Arachnoid mater
7
Q
is a well-recognized finding in patients witha unilateral disease of the cerebral hemispheres, especially withlarge, posterior lesions.
A
Horizontal nystagmus
8
Q
Physiology or function of the sclera:
A
- contain parts of the eyeball2. To maintain the globular shape of the eye3. To serve as the protective covering4. To aid in excluding extraneous light since it is opaque
9
Q
retracts the eyelid to”open” the eye. This can be either voluntarily or involuntarily.
A
levator palpebrae superioris muscle
10
Q
produces eye movement in response tochanges in head position
A
Vestibulo-ocular reflex (VOR)
11
Q
those lines from which the object and image distances are measured
A
Principal Plane (bending plane)
12
Q
he was able to see under the most favorable condition as far as 835 mu
A
Helmholtz
13
Q
innervated by the parasympathetic branch of the CN III.
A
SPHINCTER PUPILLAE
14
Q
inflammation of the iris alone,
A
•iritis:
15
Q
vergence induced by a stimulus to binocular fusion.
A
Fusional vergence
16
Q
radius of curvature of cornea
A
7.7mm
17
Q
the cells which we have called receptors belong to the class termed epithelial cells in histology; more specifically we may call them neuro-epithelial or sensory epithelial cells. These neuro-epithelium constitutes the real receptor of what are more generally known as?
A
Sense Organs
18
Q
the innermost membrane, follows the elevations and the depressions of the brain closely. it carries in its fibrous structure, the blood vessels from which branches extend into the cortex of the brain-the nourishing (tender) membrane
A
Pia mater
19
Q
Is defined as nystagmus with the fast phase beating in an upwarddirection.
A
Upbeat nystagmus
20
Q
Posterior lens surface (maximum)
A
5.3 mm
21
Q
-nystagmus in the abducting eye-abnormalities of the abducting eye in internuclearophthalmoplegia reflect an adaptive process (Hering’s law ofequal innervation) that helps overcome the adductionweakness of the opposite eye.-Common in px’s with strabismus
A
Abducting nystagmus of internuclear ophthalmoplegia
22
Q
Basis for the Optic Constants, the position of the cardinal points, and the refractive power of both the accommodated and unaccommodated eye
A
Gullstrand’s Schematic eye
23
Q
States that when a muscle contracts, its directantagonists relaxes to an equal extent,allowing movement to take place.
A
SHERRINGTON’S LAW OF RECIPROCALINNERVATION
24
Q
cells lying in the inner nuclear layer that makecontact with cones (to convey impulses from the visual cells tothe ganglionic cells)
A
BIPOLAR CELLS
25
To measure a patient's fine depth perception through his ability to fuse stereoscopic targets.
STEREOFLY TEST
26
Curved, tube shaped structures connected to the lacrimal puncta, that tears coming from the lacrimal lake drain into. Also known as the lacrimal ducts and lacrimal canaliculi.
Lacrimal Canals (Superior & Inferior)
27
Refractive power of lens (maximum)
33 D
28
functions of the lens
• To provide accommodation, which allows theeye to clearly focus objects placed within a 6mrange• To absorb UV light
29
inflammation of the iris and ciliary body,
•iridocyclitis:
30
▪With age, the vitreous humor changes from a gel to a liquid. As it does so, the vitreous mass gradually shrinks and collapses, separating and falling away from the retina.
posterior vitreous detachment (PVD)
31
is the eye movement elicited by the tracking of a moving field.
Optokinetic nystagmus (Normal)
32
visual science that deals with the study of the structures of the eye and their functions as affected by the behavior of light such as refraction, absorption, reflection and dispersion
Physiological Optics
33
FACTORS AFFECTING PUPIL SIZE:
1. Illumination 2. Physical & mental condition 3. Size of the target 4. Distance target5. Age6. Sex7. Refractive status8. Time of the day
34
Consists of a thin, single layer of hexagonal cells which contain minute crystals of a black pigment• Its flat cells are so closely applied to the choroid that in separating the retina from the choroid, the pigment layer is apt to adhere to the choroid
RETINAL PIGMENTED EPITHELIUM (RPE)
35
devoid of dendrons but abundantly supplied with many much branching dendrons which lie wholly within the inner molecular layer
AMACRINE CELLS-
36
inflammation of the choroid alone,
•choroiditis:
37
diameter of cornea
11mm to 12mm
38
is present when the amplitude of fixation tremor is on the order of the diameter of the smallest cone.
Ocular Microtremor
39
Physiology or function of Cornea
By its rigidity, aids in giving the eyeball a constant shapeBy its transparency, it permits light to reach the anterior of the eyeBy its sensitivity, it aids in protecting the eye
40
it is about having a sense of direction while moving around an environment
Spatial Orientation
41
-Compared to tremor, it is larger and slower.-Amplitudes are 2 to 5 minutes.-Direction of drifts is apparently uncorrelated betweentwo eyes
Ocular drift
42
Tiny openings towards the inner part of each eyelid, that tears drain through.
Lacrimal Puncta
43
“ scotopic vision is a function of rods while perception of light of higher intensities of color and form is mediated by cones”
THEORY OF DUPLICITY
44
this nerve supply impulses largely to muscles and for this reason they are frequently referred as "motor nerves"
Efferent nerves
45
•Sieve-like membrane through the perforations of which rods & cones project, not a distinct membrane but a structure formed by the joining of the outer ends of the fibers of Mueller.
EXTERNAL LIMITING LAYER
46
inflammation of the entire uveal tract
•uveitis:
47
the brain and central nervous system is amply protected by this covering which envelop the brain and spinal cord quite closely
Meninges
48
•A dentate line about 8.5 mm back of the sclero-corneal junction
ORA SERRATA-
49
• Physiological diplopia for objects nearer than the point of binocular fixation.• Commonly observed by exophoric conditions.
Crossed/ Proximal Diplopia
50
after passage through canal but they are devoid of neurilemma.
•Medullated-
51
Impinging of the incident ray of light upon the eye and its transmission through to the various transparent media
Physical process
52
vertical and horizontal diameter of eyeball
22mm
53
attaching ciliary body to the limbus
Longitudinal fibers -
54
Constitutes the real “seeing”
Psychological process
55
the elements of the retina which receive the light stimulus & in which is generated the nerve impulse- “visual cells”
THE VISUAL CELLS (SENSORY EPITHELIUM)-SENSORY NEUROEPITHELIUM
56
innervated by the cervical sympathetic nerve
DILATOR PUPILLAE
57
Annular transitional zone approximately 1mm which serves as a junction or border between the sclera and the cornea
Limbus
58
Physiology or function of Choroid
1. To provide a dark chamber2. To prevent dispersion of light in order that there maybe a clear image of the object3. To nourish the outer part of the retina
59
a reflex that controls the diameter of the pupil, in response to the intensity (luminance) of light that falls on the retina of the pupil and the eye, thereby assisting in adaptation to various levels of lightness/darkness.
Pupillary light reflex (PLR)
60
the science which deals with light and its relation to sight
Optics
61
Tube shaped areas that are below the lacrimal sac and carry tears down through the bone, leading to an opening in the nose.
Nasolacrimal Ducts
62
Nerve supply of lower eyelids
branches of the infratrochlear at the medialangle, the rest is supplied by branches of theinfraorbital nerve
63
comprises 4/5 of the content of the eyeball
Vitreous humor
64
Refractive power of Lens (relaxed)
19 D
65
distance of Anterior cornea to anterior lens surface (relaxed)
3.6 mm
66
Science which deals with functions and life processes
Physiology
67
Refractive power of the eye (relaxed)
58.64 D
68
eye jumps- the sudden, quick voluntary change in fixation from one object to another.
Saccades
69
TYPES OF PUPILLARY REFLEX
1.PHOTO-PUPIL REFLEXA. DIRECT LIGHT REFLEXB. INDIRECT OR CONSENSUAL LIGHT REFLEX2. ACCOMMODATIVE OR NEAR PUPIL REFLEX3. ORBICULAR REFLEX4. CILIO-SPINAL REFLEX
70
the study of the refraction of light, especially by lenses.
Dioptrics
71
Covers 5/6 of the INTERIOR of the eye-made up of largely blood vessels-dark brown in color due to the presence of pigment cells-constitutes the nourishing coat of the eye
Choroid
72
• Physiological diplopia for objects beyond the point of binocular fixation.• Commonly observed by esophoric conditions.
Uncrossed/ Distal Diplopia
73
occupy anterior and inner portion of ciliary muscle, are oriented parallel to the limbus, and influence Accommodation
Circular fibers -
74
some other kind of efferent nerves that transmit impulses to the glands
secretory nerves
75
•Forms the 90 degree angle
NERVE FIBER LAYER
76
points where axial and secondary rays pass through without undergoing refraction or is unchanged regarded as its "optic center"
Nodal Point
77
forms the posterior opaque 5/6 fibrous protective coat
Sclera
78
outermost layer of the choroid consisting of larger diameter blood vessels
Haller's layer -
79
layer of medium diameter blood vessels
Sattler's layer -
80
for the effectors to adjust the animal to the environmental changes, the disturbances set up in the receptors must be carried to the effectors. This is accomplished by strands of protoplasm which connect these two organs (effectors & receptors).commonly known as "neurons".
Physiological Connectors
81
Posterior lens surface radius (relaxed)
6.0 mm
82
thickness of crystalline lens
3.6 to 4 mm thick
83
a theoretical line passing through all the six cardinal points
Principal Axis
84
connects longitudinal and Circular fibers
Radial fibers
85
the orbit is formed by seven of the cranial bones which are?
SphenoidZygomatic boneMaxillaryLacrimalFrontalPalatineEthmoid
86
4 surfaces of the eye
1. Anterior and posterior corneal surface; 2. anterior and posterior crystalline lens surface
87
•Between nerve fiber layer & vitreous; the inner limit of the retina; partially performed by the ends of the Mueller’s fibers
INTERNAL LIMITING LAYER
88
is measured by bringing an object to the nose and observing when the patient sees double, or one eye deviates out.
Near point of convergence (NPC)
89
macula has a central depression where our keenest vision is located
Fovea centralis
90
A small open area of the conjunctiva of the eye where tears collect after bathing in the front part of the eyeball
Lacrimal lake
91
– Demonstrated that accommodation could not be caused by varying the refracting power of the cornea or by varying axial length of the eye. demonstrated that the lens was responsible for accommodation by showing that an aphakic eye was unable to focus on a near object.
Thomas young
92
envelopes the posterior 2/3 of the eyeball is a thin membrane sac known as the?-also known as the "fascia bulbi"
Tenon's capsule
93
Tube shaped areas that release tears from the lacrimal gland into the top part of the conjunctival sac
Excretory lacrimal ducts
94
distance of Anterior cornea to anterior lens surface (maximum)
3.2 mm
95
forms a protective cushion for the eyeball
adipose (fat) tissue
96
|is the simultaneous movement of both eyes in opposite directions to obtain or maintain single binocular vision.
VERGENCE
97
- Superimposition or simultaneous (first degree fusion) of two ocular images requires stimulation of retinal areas having common visual directions.
Simultaneous Perception
98
is a multivectorial nystagmus (ie, horizontal, vertical,circular, elliptical) with an equal velocity in each direction that may reflect brainstem or cerebellar dysfunction.
Pendular nystagmus
99
a very dense membrane of connective tissue and adheres quite closely to the bones of the skullmeans hard or severe
Dura mater
100
ability of the eye to adjust to an increase or decrease in its irritability to an increase or decrease of stimulus
❖RETINAL ADAPTATION-
101
Tiny openings towards the inner part of each eyelid, that tears drain through.
Lacrimal Puncta
102
retina is a thin delicate membrane which is almost transparent and of purplish red in color due to
Rhodopsin or visual purple
103
|It is seen when an individual follows a moving object with their eyes, which then moves out of the field of vision at which point their eye moves back to the position it was in when it first saw the object
Optokinetic reflex
104
Physiology or function of retina:
1. for the perception of light energies2. for the transmission of the visual and pupillary impulses
105
Small organs that release tears.
Lacrimal glands
106
Vitreous humor contains?
1. 98.5% water2. trace of sodium chloride3. albumin4. vitrein 5. hyaluronic acid
107
located to the temporal side of the optic disc
Macula
108
the greatest distance through which a given object could be moved to or from the eye and yet remain clearly visible with the same dioptric power
Depth of Field
109
normal Intra ocular pressure
10-22 mmhg
110
from the ganglionic cell layer to their exit through the canal
•Non-medullated fibers-
111
covers the fundamental knowledge based on scientific principles which support the application of these principles in optometric solutions which can assist the optometrist in optometry care and practice
Visual optics
112
inflammation of the iris alone,
•iritis:
113
the angle subtended by the object at the nodal point
Visual angle
114
organs in which irritability to environmental changes is highly developed
Receptors
115
in his classic thesis, he described an island of vision in the sea of darkness
Traquair
116
The activity of a responding organ (muscle or gland) resulting from the stimulation of a sensory surface is called a?
Reflex action
117
the process of producing a single image from the two disparate monocular images is called?
Binocular fusion
118
in the center of optic disc found is a small depression called?
Physiological cup
119
The vascular tunic consists of three portions.
1.The choroid,2.The ciliary body, and3.The iris.
120
– Consists of newly formed soft lens fibers with nucleus
Lens cortex
121
Has a diameter of 11 to 12 mm with radius curvature of 8mm; thickness is about 0.8mm except at the margin where it measures 1.1mm
Cornea
122
It is stated that the eye gives rise to 3 distinct sensations: light, color and form sensations.✓ the primitive eye was an extremely simple organ capable only of distinguishing light.
PARINAUD (1881) - “Theory of Two Retinas”
123
* Area nearest to the pupil
* a series of ridges which roughly forms a circle formed beblood vessels
Pupillary zone
124
Physiology or function of the orbit
1. Serves as socket for the eyeball2. Contains other structures which are essential for the proper functioning of the eye
125
Anterior lens surface radius (maximum)
5.3 mm
126
locus of all object points that are imaged on corresponding retinal elements at a given fixation distance.
Horopter
127
layer of capillaries
Choriocapillaris -
128
Three most important fissure and foramina in the bony wall
naso-lacrimal canalOptic ForamenSuperior Orbital Fissure
129
-eyes cannot be maintained at an eccentric orbital position and are pulled back toward primary position by the elastic forces of the orbital fascia.-Congenital nystagmus
Gaze-evoked nystagmus
130
points toward which the rays of light coming from infinity passing through the lens focus or appear to focus
Principal Foci
131
states that existence of corresponding retinal elements with their common relative subjective visual direction is the essence of binocular vision.
Law of Sensory Correspondence
132
a portion of the optic nerve which is insensitive to light and measures about 1.5 mm in diameter
Optic disc or blind spot
133
caused by dysfunction of the vestibular part of the inner ear, the nerve, the vestibular nucleus within the brainstem, or parts of the cerebellum that transmit signals to the vestibular nucleus
Vestibular nystagmus (Dysfunction)
134
•Contains the cell bodies of rods and cones
OUTER NUCLEUS LAYER
135
- reflection of objects from the structures of the eye
- images of the retinal blood vessels
Purkinje images
136
they set the low limit at 320 mu, but to see this far into the violet end of the spectrum (shortest wavelength), the light must be very intense.
Glancy and graham
137
diameter of crystalline lens
9mm
138
Holds that if the two images of an object fall upon identical points in the retinas, the object is seen as one, but if the two images fall upon unidentical or disparate points, the object is seen as two.
Doctrine of Corresponding Points
139
Three kinds of meninges
Dura materArachnoid mater Pia mater
140
is defined as nystagmus with the fast phase beating in an downward direction
Downbeat nystagmus
141
4 process of seeing
Physical ProcessPhysiological ProcessNeuro-muscular ProcessPsychological Process
142
a point on the eye where the principal plane passes through
Principal Point
143
Anterior Cornea radius during Relaxed and maximum Accommodation
7.7 mm
144
where does the crystalline lens receive its nutrition?
from the aqueous humor andvitreous humor
145
is the simultaneous inward movement of both eyes toward each other, usually in an effort to maintain single binocular vision when viewing an object.
Convergence
146
Crystalline lens comprises of?
• 65% water• 30 – 35% proteins• 19% phospholipids• 0.66% cholesterol• 0.8% - 1.2% salts (Na, K, Ca)
147
Transformation of the radiant energy in, or at, the neuro-epithelium of the retina into some other form of energy capable of stimulating the receptor cells
Physiological process
148
protrusion of the eye due to excessivestimulation of the smooth muscle fibers found in the capsule
Exophthalmos
149
thickness of iris
0.5mm
150
Nerve supply of upper eyelids
the infratrochlear, supratrochlear, supraorbital andthe lacrimal nerves
151
a movement of the eye that happens automatically as a reaction to something. (involuntary)
Reflex eye movement
152
also known as the blink reflex, is an involuntary blinking of the eyelids elicited by stimulation of the cornea (such as by touching or by a foreign body), or bright light, though could result from any peripheral stimulus. Stimulation should elicit both a direct and consensual response(response of the opposite eye).
Corneal Reflex
153
Forms the 1/6 of the fibrous tunic
Cornea
154
Refractive power of the eye (maximum)
70.57 D
155
* Attached to the anterior portion of the ciliary body
* Root of the iris
Ciliary zone
156
Other structures found in the orbit
1. Extrinsic muscles of the eye2. Levator muscles of the lids 3. Plain orbital Muscles4. Orbital Fascia5. Blood vessels and nerves of the eye
157
connect the cones with each other- called association fibers by which one part of the retina may influence another
HORIZONTAL CELLS-
158
consists of elevation and intorsion of one eyeand depression and extorsion of the fellow eye that alternates everyhalf cycle.-One eye rises and intorts; other eye falls and extorts.
Seesaw nystagmus
159
vergence due to the awareness of a fixation object being near or far in the absence of disparity and of cues for accommodation. This includes also vergence that is due to a subject's intent to fixate an object in the dark.
Proximal vergence
160
Functions of the iris
1. Reduce spherical and chromatic aberration2. Regulate the amount of light entering the eye3. increase in depth of focus
161
-(third degree fusion) is the binocular visual perception of three dimensional space based on retinal disparity.- Perception of depth in fused images- Pinnacle of sensory fusion ability.
Stereopsis
162
the extent to which the image may be located in front or behind the retina and still appear to be clear
Depth of focus
163
- It is the act, condition or process of directing the eye towards the object of regard causing, in a normal eye, the image of an object to be centered on the fovea.
FIXATION
164
Hollow spaces that the lacrimal canals drain tears into.
Lacrimal Sac
165
composed of the afferent nerve, the efferent nerve, and the connection, or junction, between these two, known as?
Reflex center
166
antero-posterior diameter of eyeball
24mm
167
the object of the protoplasmic changes in the receptor as the result of stimulation is to "acquaint" the organism with the environmental changes and thereby "enable organism to adjust itself to these changes".
Effectors
168
is the simultaneous outward movement of both eyes away from each other, usually in an effort to maintain single binocular vision when viewing an object
Divergence
169
– Consists of dense central mature fibers that lost their nuclei and no longer in contact with the posterior lens capsule
Lens nucleus
170
If corresponding points have a geometrically regular horizontal distance from the two retinas, the longitudinal horopter curve would be a circle passing through the center of rotation of the two eyes and the fixation point.
Vieth-Muller Circle
171
means relating to the eyelids. Its key function is to regularly spread the tears and other secretions on the eye surface to keep it moist, since the cornea must be continuously moist.
Palpebra
172
The generation of nerve impulse in the retina and its transmission by a chain of neurons to the central nervous system
Neuro-muscular process
173
-Nystagmus resulting from malfunction in the saccade and pursuit gaze systems is much less common than that due to fixation malfunction-is a rhythmic rotation of the eyes in which the 12 o'clock meridian of the limbus rotates, causing either intorsion or extortion
Torsional (rotary) nystagmus
174
a condition of involuntary eye movement, acquired in infancy or later in life, that may result in reduced or limited vision. Due to the involuntary movement of the eye, it is often called "dancing eyes"
Nystagmus
175
inflammation of the choroid and retina,
•chorioretinitis:
176
Some cues that can be processed by just one eye, which is why they are referred to as?
Monocular cues
177
•Contains amacrine, bipolar, & horizontal cells, nuclei of Mueller’s fibers& capillaries of CRA
INNER NUCLEAR LAYER
178
A structure dividing the 2 zones of theirs, which is 2mm from the pupillary zone.
Collarette
179
Smooth homogenous, transparent, acellular, structureless, highly elastic which envelopes the lens
lens capsule
180
situated at the apex of the orbit, is the passageway for the optic nerve and ophthalmic artery
Optic Foramen
181
make connections with the axons of the bipolar cells
GANGLIONIC CELLS-
182
diameter of iris
11mm
183
innermost layer of the choroid
Bruch's membrane -
184
-The presumed mechanism is disruption of the vestibulo-ocular tracts atthe pontomedullary junction.
Periodic alternating nystagmus
185
the simultaneous occurring cyclorotation (torsional movement)of both eyes which is performed in opposite directions to obtain or maintain single binocular vision.
Cyclovergence
186
it contains 98.1% water with a trace of sodium chloride and fills the space between cornea and the lens
Aqueous humor
187
it is around 1mm thick at the exit of the optic nerve and 0.4 mm at the corneal margin-it is pierced by the optic nerve at about 2-3mm to the nasal side below the horizontal plane
Sclera
188
thickness of cornea
0.8mm to 1.1 mm
189
Two Distinct visions must be mediated by 2distinct neural mechanisms.
Duplex Vision
190
in addition to the sensory surface and the responding organ, a line of communication between these two is known as?
Reflex arc
191
passageway for the 3rd, 4th and 6th cranial nerve, three branches of the ophthalmic division of the 5th cranial nerve, branch of the sympathetic nerve and the ophthalmic vein.
Superior Orbital Fissure
192
a reflex action of the eye, in response to focusing on a near object, then looking at distant object (and vice versa),comprising coordinated changes in vergence, lens shape and pupil size
Accommodation reflex
193
distance of Anterior cornea to posterior lens surface (relaxed and maximum)
7.2 mm
194
a delicate diaphragm located at the most anterior portion of the uvea and is situated between the cornea and the lens
IRIS
195
Are kind of fixational eye movement. They are small, jerk-like involuntary eye movements, similar to miniature versions of voluntary saccades.
Microsaccades
196
demonstrates, therefore, that (1)distant and near objects cannot be simultaneously focused on the retina, and (2) a change in dioptric power of the eye is therefore necessary to see clearly at various distances.
Christopher Scheiner
197
prolongation and thickening of the choroid-forms a ring within the eye about 6mm wide
Ciliary Body
198
•Synapse of axons of bipolar cells & dendrites of ganglionic cells &amacrine cells
INNER MOLECULAR LAYER (INNER PLEXIFORM LAYER)
199
•Contains large cell bodies whose neurons send axons into nerve fiber layer
GANGLIONIC CELL LAYER
200
Functions of Ciliary body
1. because of its "Vascularity" it nourishes the eye2. By its ciliary muscles, it aids in the process of accommodation3. Serves as attachment for the zonule of zinn
201
blur-driven vergence is that portion of the range of inward rotation of both eyes that occurs in response to an increase in optical power for focusing by the crystalline lens.
Accommodative vergence
202
Vergence due to normal extraocular muscle tone, with no accommodation and no stimulus to binocular fusion.
Tonic vergence
203
The bones that surround the lacrimal sac. They are located on each side of the nose, within the inner part of the eye socket.
Lacrimal Bones
204
the dorsal root fiber conveys impulses, from a sensory surface to the spinal cord, hence it is called an? Also known as sensory nerves
Afferent nerves
205
if two objects are roughly the same size, the object that looks the largest will be judged as being the closest to the observer
Relative size
206
as you are moving, objects that are closer seem to zoom by faster than do objects in the distance
Motion parallax
207
objects that are farther away seem to be blurred or slightly hazy
Aerial Perspective
208
Parallel lines appear to meet as they travel into the distance
Linear perspective
209
Refers to visual perceptions that are produced or influenced by the structures of one's own eye
Entopic imagery (Entopic phenomenon)
210
consisting of flashes of light that were likened to the appearance of flashes of lightning
-associated with stress
Moore's lightning streaks
211
- appearance of tiny bright dots moving rapidly along squiggly lines in the visual field
- caused by white blood cells moving in the capillaries in front of the retina
Blue field phenomenon (Scheerer's phenomenon)
212
is the perception of light without light actually entering the eye
Phosphene
213
phosphene brought by rapid movement of the eye
Flick Phosphene
214
- after image due to over stimulation of cones
- opposite color of the original object
Negative after image
215
refers to an image continuing to appear in one's vision after the exposure to the original image has ceased
Afterimage
216
described a region of luminance levels and color temperatures that are often viewed as comfortable or pleasing to an observer
Kruithof Curve
