Brainscape's Knowledge GenomeTM

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


See full index

Neuroanatomy > EYE MOVEMENTS - MODULE > Flashcards

EYE MOVEMENTS - MODULE Flashcards

1
Q

Which 3 cranial nerves innervate the extraocular muscles

A
  • Abducens (CN VI)
  • Trochlear (CN IV)
  • Oculomotor (CN III)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What muscle is innervated by the abducens nerve

A

Lateral rectus

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

what muscle is innervated by the trochlear nerve

A

superior oblique

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

what muscle(s) are innervated by the oculomotor nerve

A
  • Superior rectus
  • medial rectus
  • inferior rectus
  • inferior oblique
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is gaze

A

the coordinated movements of the right and left eyes to a visual target

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

How does communication between ocular nuclei occur

A

via the ascending medial longitudinal fasciculus

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

what is the medial longitudinal fasciculus

A

a fiber tract that is critical for coordianted eye movements

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

Where is the vertical gaze center located

A

in the midbrain reticular formation and pretectal area

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

where is the horizontal gaze center located

A

in the pons - paramedian pontine reticular formation

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

The horizontal gaze center gives input to the ____ to direct gaze to the _____

A

abducens nucleus

ipsilateral side

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

A subset of neurons projects from the abducens nucleus to what muscle

A

ipsilateral lateral rectus

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

A second subset of neurons projects from the abducens nucleus to the ___ and the to what muscle

A

oculomotor nucleus

left medial rectus muscle

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

What are saccades? What do they allow us to do?

A

rapid, simultaneous movements of the eyes that redirect the gaze between different fixation points
Allow us to scan the environmetn

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

what are reflexive saccades

A

visually guides sacced in response to external cue

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

What are volitional saccades

A

voluntary eye movements indenpendent of any visual stimulus

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

saccadic eye movement can be initiated by ___ or ____

A

cortical or subcortical areas of the brain

17
Q

Cortical initiation of saccades comes from..

A

frontal eye fields located in the supplementary motor areas and extending anteriorly

18
Q

Cortical initiation of saccades is the main input for..

A

volitional saccades

19
Q

subcortical initiation of saccades comes from?

A

superior colliculus located in the posterior midbrain

20
Q

subcortical initiation of saccade is the main input for…

A

reflexive saccades

21
Q

What is the pathway for reflexive saccades

- this card is frigged im sorry

A
  • Visual stimulus appear in visual field and active contralateral frontal eye field and the contralateral superior colliculus
  • within the superior colliculus, neurons in the superficial visual layer are activated and project to corresponding neurons in the deep motor layers
  • neurons from superior colliculus activate contralateral horizontal gaze center which then initiated gaze in ipsilateral direction
22
Q

The descending MLF allows communication between…

A

nuclei and the brainstem

23
Q

the descending MLF comprises the ___ and ____

A

medial and lateral vestibulospinal tracts

24
Q

The desceding MLF arises from the ____ and influences

A

Vestibular nuclei and influences muscle tone for balance and posture and it critical in the positioning of the head and neck

25
Q

In smooth pursuit the 1st step is for the primary visual cortex and the frontal eye fiels to send projections to the…

A

ipsilateral pontine nuclei

26
Q

in smooth pursuit, fibres from the pontine nuclei project across the midlines into …

A

the contralateral cerebellum

27
Q

In smooth pursuit fibres project from the cerebellum to the…

A

ipsilateral vestibular nuclei

28
Q

in smooth pursuit, fibres from the vestibular nuclei cross the midline and project tooo….

A

the contralateral abducens nucleus

29
Q

what is the end goal of smooth pursuit

A

to coordinate movement of both eyes to look in the same direction

30
Q

What is the vestibulo-ocular reflex

A

rapid adjustment of eye movement in response to movement of the head (to counteract it)

31
Q

why do we need to have the vestibulo-ocular reflex

A

to stabilize image on the retina and prevent the image blurring

32
Q

how many dimensions does the vestibo-ocular reflex occur in

A

3 dimensions

33
Q

what initiates the VOR

A

shifting of fluid in the horizontal canal (shifts opposite to head movement)

34
Q

during the VOR when fluid shifts in the horizontal canal what is activated

A

sensory cells

35
Q

in the VOR, the sensory cells once activate project to …

A

the ipsilateral vestibular nuclei

36
Q

in the VOR, fibres from the vestibular nuclei cross the midline and project to the

A

contralateral abducens nucleus

37
Q

in the VOR eyes move in what direction

A

opposite to the head movement

Neuroanatomy (23 decks)

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