Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuroscience > Eyes and Visual Processing > Flashcards

Eyes and Visual Processing Flashcards

1
Q

What eye muscles are supplied by CN 3?

A

R –> S, I, M

O –> I

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

What eye muscles are supplied by CN 4?

A

Superior Oblique

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

What eye muscles are supplied by CN 6?

A

Lateral Rectus

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

What are the systems that control eye movement?

A

Oculomotor System: w head fixed

Head Movement System: when head moves (oculomotor and vestibular sytem)

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

What shape of movement must the patient move their eye in order to test the muscles in isolation?

A

Double H

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

SR and IR require the eyes to be ———- to test their function

A

Abducted

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

SO and IO require the eyes to be ——— to test their fucntion

A

Adducted

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

Midbrain reticular formation control movement of gaze in what plane?

A

Vertical via interactions of nerves 3 and 4

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

Pontine reticular formation control movement of gaze in what plane?

A

Horizontal Via the interaction of nerves 3 and 6

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

What is the MLF?

A

Medial Longitudinal Fasciculus –> White matter tract that connects several CN nuclei

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

what are the two types of neurons found in the gaze control pathway? and when do they signal?

A

Burst Neuron –> fire before movements

Ommnipause Neuron –>keep eyes in one position fire when there is no movement

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

how many types of bursting neurons are there and what do they do?

A

Excitatory: to Ipsilateral nuclei of different type
Inhibitory: to contralateral nucleus of same type

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

Of all the nerves controlling gaze which one is the only one that crosses the midline and supplies contralateral structures

A

Trochlear

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

what is optokinetic movement of the eyes?

A

holds image n the retina during sustained head movement

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

what does the vestibulo-ocular movement of the eye do?

A

holds image still in retina during brief head movements

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

if we want to move our eyes to the left which muscles must be activated?

A

R Medial Rectus (CN3)

L Lateral Rectus (CN6)

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

if we want to move our eyes to the left which nucleus must be activated first?

A

the left Pontine Reticular Formation

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

if we want to move our eyes to the left which nucleus must be inhibited first?

A

L CN3

R CN6

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

if we want to move our eyes to the left which nucleus must be activated second? third?

A

L CN6

and through the MLF the R CN3

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

if we want to move our eyes to the left which nuclei must be inhibited first? second?

A

R CN6

L CN3

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

information for eye movements comes mainly from?

A

Frontal Eye Fields Cortex

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

Frontal Eye Fields Cortex controls saccades in the ——– direction

A

Contralateral (aka activation of the right moves eyes to the left)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

if there is a dissection of the Frontal Eye Fields Cortex gaze moves towards/away from lesion

A

Towards

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What do the semicircular canals signal?

A

Head Position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Otoliths in the ear sense what?

A

Linear acceleration

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are the otoliths?

A

Utricle and Saccule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

the hair cells of the vestibular apparatus signal when there is desaceleration T/F

A

F, they do not signal when there is desaceleration or movement stops

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

In what direction must the fluid motion go in order to increase signalling in the semi-circular canals?

A

in the same direction of the semi-circular canal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

if motion causes increased firing in one ear what does it cause in the other?

A

decreased signalling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Movement towards the right induces activation of the R vestibular nucleus T/F

A

T

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Activation of the L vestibular nucleus inhibits the R abducens nucleus T/F

A

F. Causes activation of the R abducens nucleus in order to keep the image in the retina

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What do the ganglion cell axons of the eye target?

A

Thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What do the M ganglion cells ‘see’

A

Magnocellular = Motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What do the P ganglion cells ‘see’

A

Parvocellular = Colour and Visual Acuity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is in larger % M or P ganglion cells

A

P

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

The optic chiasm sits in front of the —-(1)—– and is surrounded by the —(2)——

A

1 Pituitary

2 Internal Carotids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What part of the RETINA does not decussate?

A

Temporal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What part of the VISUAL FIELD information does not decussate?

A

Nasal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

Image on the left nasal visual field is seen by which optic cortex

A

Right

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

the thalamus is the relay center of all information except

A

olfactory information

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Where is the cell body and nuclei of the ganglion cells located?

A

thalamus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Lateral Geniculate Nucleus (Thalamus) receives information related to what sense

A

Vision

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

Medial Geniculate Nucleus receives information related to what sense

A

Audition

44
Q

Connection between Visual Cortex and LGN

A

Optic Radiations (White matter)

45
Q

How many layers does the LGN have? and how many come from each eye

A

6 (3)

46
Q

out of the six layers in the LGN to which do the M ganglion cells synapse?

A

1-2 (one of each eye)

47
Q

out of the six layers in the LGN to which do the P ganglion cells synapse?

A

3-6 (two for each eye)

48
Q

Where is the Primary Visual Cortex Located?

A

Occipital Lobe around the calcarine fissure

49
Q

What is Retinotopic Organisation?

A

Cells from the retina that are close together tend to remain and signal to the same area

50
Q

Which 1/2 visual field from each eye is projected in the contralateral eye?

A

Temporal

51
Q

Where is foveal vision decoded?

A

at the most occipital part of the cortex

52
Q

What artery supplies the primary visual cortex?

A

Posterior Cerebral Artery

53
Q

Why does macular sparing occurs?

A

because the central vision of each eye in the cortex is supplied by a different artery

54
Q

What are ipGC?

A

intrinsically photosensitive Ganglion Cells

55
Q

What pigment is found in ipGC?

A

Melanopsin

56
Q

if light is shinned on ipGC what happens?

A

Depolarisation and increased signalling

57
Q

What muscle is under sympathetic activation in relation to the pupillary reflex?

A

Dilator Pupillae

58
Q

What muscle is under parasympathetic activation in relation to the pupillary reflex?

A

Sphincter Pupillae (S parasympathetic)

59
Q

Where do the ipGC signal to in order to code for circadian rhythm and sleep regulation?

A

Suprachiasmatic Nucleus (Hypothalamus)

60
Q

Where do the ipGC signal to in order to code for pupillary response?

A

Pretectum (Midbrain) [Optical Pretectal Nucleus]

61
Q

Where do the ipGC signal to in order to code for photophobia (allodynia)?

A

Posterior Nucleus of Thalamus

Dura —Trigeminal –Brainstem—Thalamus

62
Q

the efferent signal from the pupillary reflex comes from which nuclei?

A

Edinger-Westfal Nucleus

63
Q

If there is an afferent defect would the ipsilateral pupil constrict? the contralateral? [in re to light]

A

No

64
Q

If there is an efferent defect would the ipsilateral pupil constrict? the contralateral? [in re to light]

A

No, Yes

65
Q

What do M cells decode?

A

Movement

66
Q

In the visual cortex what layer is the sensory cortex for input of visual information?

A

Sensory cortex is always layer 4

67
Q

Layer 4 is divided into 2 subdivisions they are? and what type of cells synapses there?

A

4Cα M

4Cß P

68
Q

Where do M and P cells target?

A

LGN (lateral geniculate nucleus)

69
Q

Where is the first point where visual information gets combined?

A

Layer 4B

70
Q

Where does information from the layer 4Cα gets relayed to? and what information is sensed here?

A

Layer 4B

Motion

71
Q

What type of selectivity does the cells in layer 4B show?

A

Directional Selectivity: increased firing only on movement of light in a specific direction

72
Q

Where is all visual information processed first in the brain?

A

Primary Visual Cortex (V1)

73
Q

From the Primary Visual Cortex (V1) how many pathways can visual information take? what are they?

A

Where? –> Dorsal Pathway

What? –> Ventral Pathway

74
Q

what type of cells signal their information via the WHERE pathway? and where is this pathway located?

A

Movement: M cells (codes for info above certain speed)

Middle Temporal Lobe [Area MT]

75
Q

what type of cells signal their information via the WHAT pathway? and where is this pathway located?

A

Visual Acuity P cells

Inferior Temporal Lobe

76
Q

The area MT receives what type of information and from where?

A 
Motion
Via V1(4B), V2 and V3
77
Q

Area MT has small receptive fields to better code for movement T/F

A

F Large visual fields

78
Q

Define: Blind Sight

A

pathway from the LGN to the area MT that can be intact in some blind people allowing them to ‘see’ objects due to their movement

79
Q

what is the visible range of light?

A

400-700 nm (430B,530G,560R)

80
Q

ganglion cells react differently depending on where the light is shined on their RF T/F

A

T

81
Q

What part of the visual cortex is mainly responsible for colour vision?

A

V4

82
Q

in the area V4 cells have —-(1)—- selectivity and —–(2)—- selectivity

A

1 Orientation

2 Colour

83
Q

What is area IT important for? and is connected to what other important area?

A

Recognition of faces and Visual Memory

V4

84
Q

What is a monochromat?

A

only one type of functional cone available

85
Q

Define: Dichromat

A

2 types of functional cones

86
Q

Anomalous Trichomacy is

A

3 types of cones but one expresses an abnormal pigment

87
Q

How do you test for Anomalous Trichomacy?

A

Pseudoisochromatic Plates

88
Q

What is the most common form of colour deficiency?

A

Anomalous Trichomacy

89
Q

What does PROTAN stand for?

A

problems with the Red Cone
PROTANope–> no red cone
PROTANomal –> abnormal red cone

90
Q

What does DEUTAN stand for?

A

problems with the green cone
DEUTANope-> no green cone
DEUTANomal–> abnormal green cone

91
Q

What does TRITAN stand for?

A

problems with the blue cone
TRITANope-> no blue cone
TRITANomal–> abnormal blue cone

92
Q

Can there be a monochromat protanomal with the other 2 cones intact?

A

No, monochromat only has 1 cone type

93
Q

Can there be a trichromat protanomal with the other 2 cones intact?

A

Yes

94
Q

What is visual acuity? what is the best result (normal)? what is legal blindness?

A

ability to distinguish fine detail (6/6)

6/60

95
Q

what is the last cell light hits when it enters the eye?

A

the photoreceptorvision in light (6/6)

96
Q

what is phototopic vision?

A

vision in light (6/6)

97
Q

what is scotopic vision?

A

vision without light (6/60)

98
Q

What is the pathway for light to reach the photoreceptors?

A

Ganglion cell
Bipolar cell
Photoreceptors

99
Q

what is the main photopigment found in cones and rods?

A

Rodopsin
Conopsin
there are less cones than rods and they are less sensitive

100
Q

what is the main photopigment found in cones and rods?

A

the ganglion cells

glutamate

101
Q

horizontal cells receive input and provide output to —–1—– and respond to light by —–2—- and releasing —-3—

A

1 photoreceptors
2 hyperpolarising
3 GABA

102
Q

Amacrine cells allow for coding of —1— and are mostly —2—

A

movement

2 inhibitory

103
Q

what are the modulatory cells of the eye?

A

amacrine and horizontal cells

104
Q

in which layer are bipolar cells found? how many types are there?

A

Nuclear Layer
10 (9 for cones)
Allow for colour vision and acuity

105
Q

light —-1—- the photoreceptors induing a decreased release of —-2— activating on/of —3—-

A

1 hyperpolarise
2 glutamate
3 ganglion cells

106
Q

if light activates the horizontal cells there would be

A

hyperpolarisation and release of gaba

107
Q

light activates —-1—- which in turns activates a —–2— turning on a —-3— reducing the levels of —-4— closing —-5—-

A 
rhodopsin
g-coupled protein
phosphodiesterases
cGMP
cGMP dependant Na+ channels

Neuroscience (31 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions