Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Advanced Neuroanatomy 1-8 > Visual Systems > Flashcards

Visual Systems Flashcards

1
Q

What three layers form the eyeball

A

Fibrous
Vascular
Inner layer- Retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Fibrous Layer

A

Outermost layer
Consists of Sclera and cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the Sclera of the fibrous layer

A

Makes up most of the fibrous layer, visible as the white part of the eye, provides attachment to the extraoccular muscles (responsible for movement of eye)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cornea (fibrous layer)

A

transparent and positioned centrally in the front of the eye.
Light entering the eye is refracted by the cornea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Vascular Layer

A

Underneath the fibrous layer, consists of the choroid, ciliary body and iris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Choroid (Vascular layer)

A

layer of connective tissue and blood vessels, which provides nourishment to outer layer of retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Ciliary Body ( Vascular Layer)

A

comprised of ciliary muscle and processes.
Ciliary muscle consists of smooth muscle fibres which are attached to the eye by ciliary processes

Controls the shape of the lens and contributes to the formation of aqueous humor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Iris ( Vascular Layer)

A

Circular structure with an aperture in the centre (pupil)

The diameter of the pupil is altered by smooth muscle fibers within the iris, which are innervated by the ANS

Situated between the lens and the cornea.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Inner layer= Retina

A

Light detecting component, consisting of two layers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the two layers of the Retina

A

Pigmented Outer layer
Neural Inner layer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Pigmented Outer Layer of Retina

A

Formed by single layer cells

Attached to choroid , supports choroid in absorbing light, prevents scaterring of light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Neural Inner Layer

A

Consists of photoreceptors = light detecting cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Macula

A

Area in the centre of the retina
Yellowish in colour, highly pigmented
Contains a depression called the fovea centralis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Fovea Centralis

A

High concentration of light detecting cells
Responsible for high acuity of vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Optic Disc

A

Blind Spot
Area where the optic nerve enters the retina
Contains no light detecting cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Macula Lutea, Fovea Centralis

A

Small yellowish area lateral to the optic disc, highest visual sensitivity

Fewer rods (functions in dim light)

More Cones (bright light)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Vitreous Body/Humor

A

Two fluid filled areas of the eye
- Anterior Chamber (located between the cornea and iris)

-Posterior Chamber (located between iris and ciliary processes)

Filled with aqueos humor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Function of Vitreous Body/ Humor

A

Clear like plasma fluid nourishes and protects the eye

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Clinical relevence of Vitreous Body/ Humor

A

glaucoma is when the drainage of aqueous humor is obstructed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Blood Supply of Eyeball

A

Receives arterial blood via the opthalamic artery (branch of the internal carotid)

Venous drainage is carried out by the superior and inferior opthalamic veins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Lens

A

Located between the vitreous humor and pupil

Shape of the lens is altered by ciliary body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Clinical Relevence of the lens

A

old age, the lens can become opaque which is a Cataract

23
Q

Accomodation

A

Ability of eye to change the focal length of lens by changing the curvature of the eye lens

Change in Refractive Power

24
Q

Unaccomodated lens

A

when viewing distant objects the lens is made relatively thin and flat and has the least refractive power

25
Accomodated Lens
for near vision the lens becomes thicker and rounder and has the most refractive power this involves a change in the ciliary muscles surroudning the lens
26
Ametropia
a group of visual disorders caused by errors in the refractive power of the eye
27
Emmetropia
normal refractice condition of the eye
28
Myopia
Nearsightedness Close up objects look clear but distant objects are blurry Cause: corneal surface too curved Correction: concave (-) lens
29
Hyperopia
Farsightedness Distant objects are usually seen more clearly than close ones Cause: eyeball being too short or refracting system too weak Correction: convex (+) lens
30
How many layers in the retina
8
31
Name 5 types of neurons in the retina
Photoreceptors Bipolar Cells Ganglion Cells Horizontal Cells Amacrine Cells
32
Three neuron chain of the retina
photoreceptors- bipolar cells- ganglion cells Major route of info flow from photoreceptors to optic nerve
33
Photoreceptors of optic nerve
rods and cones
34
What do rods and cones both have
Outer segment - composed of membranous disks that contain light sensitive photopigment Inner Segment- contains the cell nucleus and gives rise to synaptic terminals that contact bipolar or horizontal cells
35
How can photoreceptors be distinguished
Shape Type of photopigment Distribution across retina Pattern of synaptic connections
36
Rod
Low spatial resolution Extremely sensitive to light Specialised for sensitivity at the expense of resolution Photopigment: contain single (RHODOPSIN) Function: peripheral vision and in vision under low light conditions
37
Cone
High spatial resolution Insensitive to light Colour vision Specialised for acuity at the expense of sensitivity Photopigment : photopsin Three types of cones that differ in the photopigment they contain Function: function under bright light and are responsible for the central discriminative vision and for colour detection
38
Cone Cells and Colour Blindness
Three types of cones differ in photopigment Each of these pigments has a different sensitivity to light of different wavelengths, referred to blue, green and red or short, medium and long wavelength cones
39
What is color blindness
the inherited failure to make cone pigments Alteration on absorption spectre of cone pigments
40
Retinis Pigmentosa
genetic disorder characterised by progressive vision loss due to a gradual degeneration of photoreceptors Progressive loss of vision >> dark clumps of pigment visible in eye
41
Symptoms of retinis pigmentosa
Initially night blindness Reduced peripheral vision Pigment migration of disrupted retinal pigment epithelium into the retina, over years cones also degenerate
42
Macular degeneration
Loss of cone function Most commone in people over 55 Risk Factors>> cvs disease, smoking, light, nutrition
43
WET AMD
10% of all cases progress rapidly Abnormal blood vessel growth occurs under the macula >>leak fluid into retina, damaging the photoreceptors Therapy = laser therapy
44
DRY AMD
90% of all cases Gradual disappearance of retinal pigment epithelium
45
What is the visual pathway
Structure that are responsible for the perceiving, relaying and processing of visual info
46
Discuss Visual Pathway
look at page
47
Primary Visual Cortex (Brodmann area 17)
Also known as calcarine cortex, striate cortex or V1 Main site of input of signals coming from the retina Located on the medial aspect of the occipital lobe, in the gyrus superior and inferior to the calcarine sulcus.
48
What information does the primary visual cortex extract
edges depth orientation motion color of objects
49
What two pathways transfer info from primary visual cortex to association areas
Ventral Stream Dorsal Stream
50
Ventral Stream
passes through the secondary visual cortex and extends downward into the inferior temporal gyrus. The processing done by neurons in this pathway allows us to recognize faces and objects based on their size, shape, and color (what objects are?)
51
Dorsal Stream
passes through the secondary visual cortex and extends upward to the posterior parietal cortex. Neurons in this pathway provide information about the motion of objects (where object are?)
52
Pathway and Visual Field Defects
look at last three pages of notes to study this
53

Advanced Neuroanatomy 1-8 (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions