Brainscape's Knowledge GenomeTM

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


See full index

Vestibular > part 5 > Flashcards

part 5 Flashcards

You may prefer our related Brainscape-certified flashcards:
Preparativo Vestibular e ENEM flashcards
1
Q

what does the vestibulopsinal tract do

A

controls postural orientation
- collaborates with reflexes elicited by stimulation of the vestibular and visual reflexes

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

what are the components of the vestibulospinal tract

A

vestibulospinal reflex
vestibulocolic reflex

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

what does the VSR do

A

gathers static and dynamic reflexes that stablize body (input from vestibular system)
output is motor control to musculature except for neck

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

lateral VSR

A

input from otolithic organs
modulations from cerebellum via ipsilateral vestibular nuceli

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

medial VSR

A

input from SCC
from the contralateral medial vestibular nuclei and the superior and descending vestibular nuclei

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

Reticulospinal tract

A

input from all sensory and motor balance systems via vestibular nuclei

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

vestibulocollic reflexes

A

acts on muscles in neck to stabilize head in response to velocity detection from otolithic organs

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

strategies to maintain/restore balance

A

ankle
hip
stepping
suspensatory

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

How long after perception of instability do we use strategies to maintain balance

A

automatic
occur 95-90ms after perception of instability realized

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

ankle strategy

A

used when perturbation slow & low amplitude
contact surface firm, wide, longer than foot
muscles recruited distal-proximal (abs then thigh)
head movement in phase with hips
minimal energy

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

hip strategy

A

used when perturbation is fast or large amplitude
contact surface unstable or shorter than feet
muscles recruited proximal-distal
head moves out of phase with hips

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

stepping strategy

A

used to prevent fall when perturbations are fast or large amplitude
moves BOS to catch up with COG

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

suspensory strategy

A

rarely used because lots of energy
forward bend of trunk with hip/knee flexion
may progress to squatting if COG lowered

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

Cervico-occular reflex

A

eye movements driven by neck proprioceptors

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

cervico-spinal reflex

A

changes in limb position driven by neck afferent activity

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

cervico-collic reflex

A

stabilizes head movement in vertical plane

16
Q

edwalds first law

A

stimulation of SCC causes eye rotation in plane of canal being stimulated

17
Q

criteria to maintain binocular fixaiton

A
  1. eyes move opposite to head
  2. eyes rotate in sychnrony with displacement of target in space (i.e., head tilts but image stays horizontal bc eyes are counter rotating to compensate for head tilt)
18
Q

what amount of retinal slip is enough to reduce visual acuity

A

2-3 degrees

19
Q

VOR latency

A

7ms

20
Q

frequency range of head movement

A

0.5-5HZ

21
Q

frequency range of eyes during VOR

A

8Hz

22
Q

frequency of voluntary eye movement

A

can’t move faster than 1Hz

23
Q

Angular VOR responsible for

A

Gaze stabilization

24
Q

what are used for angular VOR

A

SCC

25
Q

Horizontal aVOR causes which muscles to be excited

A

ipsilateral medial rectus and contralateral rectus
i.e., head rotates R. R medial rectus and L lateral rectus excited.

26
Q

Vertical AVOR in anterior SCC causes which muscles to be excited

A

ipsilateral superior rectus and contralateral inferior oblique.

27
Q

Left anterior canal is stimulated. What way do eyes move and what muscles are stimulated.

A

Left superior rectus, Right inferior oblique
Eyes move up rotate right

28
Q

Right anterior canal is stimulated. what way do eyes move and what muscles are stimulated

A

Right superior rectus and Left inferior oblique
eyes move up and rotate left

29
Q

Vertical aVOR in posterior SCC causes which muscles to be excited

A

ipsilateral inferior rectus and contralateral superior oblique

30
Q

Right posterior canal is stimulated.what way do eyes move and what muscles are excited

A

Right inferior rectus and Left superior oblique
Eyes move down and left

31
Q

left posterior canal is stimulated.what way do eyes move and what muscles are excited

A

Left inferior rectus AND right superior oblique
eyes move down and right

32
Q

Linear VOR

A

otholithic organs

33
Q

angular VOR weakness

A

responds poorly at less than .1Hz which can interfere with smooth pursuit, OKR and velocity storage mechanism

34
Q

velocity storage mechanism

A

allows raw vestibular signals (6-7s decay) to be prolonged so aVOR can transduce sustained head rotation (20s decay)
- happens in neural integrator in brainstem

Vestibular (13 decks)

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