Brainscape's Knowledge GenomeTM

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


See full index

CSD9510 > 10 - AR Basics > Flashcards

10 - AR Basics Flashcards

1
Q

What does AR stand for?

A

Middle Ear Acoustic Reflexes

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

What does MEMR stand for?

A

Middle Ear Muscle Acoustic Reflexes

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

What is an acoustic reflex?

A

A bilaterally reflexive contraction of the middle ear muscles

  • activated by loud sound and tactile stimulation, movement
  • In humans, it is the contraction of the stapedius muscle in each ear
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The contraction of the stapedial muscle occurs when a sufficiently intense sound is presented to the ______ (eardrum/cochlea)

A

Cochlea

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

What does the contraction of the stapedial muscle do to the functioning of the auditory system?

A
  • stiffens the ossicular chain

- changes compliance of the middle ear system

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

Admittance ______(decreases/increases) with stapedius muscle contraction

A

decreases

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

The Acoustic Middle Ear Muscle Reflex uses the auditory nerve as an ____(afferent/efferent) pathway and the facial nerve (CN VII) as an _______ (afferent/efferent) pathway

A

Auditory nerve: afferent

Facial nerve: efferent

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

What is the clinical value of measuring the AR?

A
  • can help infer site of lesion (middle ear, cochlea, VIII nerve, brainstem, VIIth nerve)
  • Not useful for “lesions” above lower auditory brainstem level
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What does VCN stand for?

A

Ventral Cochlear Nucleus

  • part of the AR arc
  • stimulus travels from cochlea to CN VIII (auditory nerve) to the VCN
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What does SOC stand for?

A

Superior Olivary Complex

- during the reflex arc, the stimulus travels from the VCN to the SOC both ipsilaterally and contra-laterally

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

What is the name of CN VIII?

A

Auditory nerve

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

What is the name of CN VII?

A

Facial nerve

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

What are the 2 types of AR tests typically used today?

Describe the basic procedure.

A

AR Threshold
AR Decay

  • otoscopy and tympanometry performed first
  • immittance equipment set up for AR measures
  • probe in one ear (measures admittance change and delivers ipsilateral AR stimuli)
  • earphone in opposite ear (delivers contra-lateral AR stimuli)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How is AR measured?

A
  • measure conventional immittance
  • activate AR with sound stimulus presented to one ear (Test Ear)
  • stapedius muscle contraction increases stiffness of ME
  • change in admittance measured by probe = AR
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In AR Testing, the test ear is always the ear with the _____ (stimulus/probe)

A

Stimulus

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

Contralateral vs Ipsilateral refers to the ear with the probe placement. When measuring the LE contralateral AR, where is the probe? Where is the tone?

A

LE Contralateral:
Probe= Right Ear
Tone = Left Ear

17
Q

When measuring ipsilateral AR, what 2 types of acoustic signals is the probe delivering?

A

226 Hz probe tone (to measure acoustic admittance)

High intensity test tones/noise (to induce AR)

18
Q

Name 2 tips for accurate AR measures

A
  • ensure ear is clear of debris
  • create air-tight seal
  • instruct patient to remain still
19
Q

At what air pressure is the AR measured?

A

At the air pressure value where the compliance peak occurred (during tympanometric test)

20
Q

What does it mean if the admittance is not affected after the loud tone is delivered in the test ear?

A

The reflex is absent

21
Q

What is the lowest sound stimulus at which an admittance change can be detected above baseline noise?

A

The AR Threshold (> or = 0.02 cc or mmhos)

22
Q

What is the AR amplitude?

A

The amount of admittance change induced by sound stimulus

23
Q

What dB HL intensity level do we typically start our AR Threshold search at?

A

80 dB HL

24
Q

What is the “lowest intensity at which an admittance change is replicated” known as?

A

The Acoustic Reflex Threshold (ART)

25
Q

What frequencies do we test the AR at?

A

500, 1000 2000 (and 4000 Hz)

*4000 Hz often missing for NH individuals

CSD9510 (17 decks)

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