Auditory Evoked Potentials

Question 1

Auditory Evoked Potentials test:

Answer 1

Neural integrity

Question 2

waveforms that arise from the synchronous electrical activity of neurons in various parts of the auditory nervous system (nerve firing and transmission to the brain)

Answer 2

Auditory evoked potentials

Question 3

Auditory evoked potentials are typically elicited by _____ signals that trigger the neural response (it’s a response to sound)

Answer 3

acoustic signals

Question 4

Auditory evoked potentials must be ________

Answer 4

synchronous

Question 5

Auditory evoked potentials are recorded via __________

Answer 5

small electrodes attached to the head

Question 6

Electrical activity _______ measure hearing

Answer 6

DOES NOT - we can make inferences about hearing from this measurement

Question 7

Abbreviations that mean the same as auditory evoked potentials are: (3)

Answer 7

AEP: Auditory Evoked Potential
ABR: Auditory Brainstem Response
BAER: Brainstem Auditory Evoked Response

Question 8

In order for the brain to perceive an acoustic signal, it must pass through the _______ and then the _______

Answer 8

through the peripheral auditory system (the normal pathway) and then through the neural pathways

Question 9

In Auditory evoked potentials, ____________ neurons are activated

Answer 9

thousands of neurons are activated

Question 10

Auditory evoked potentials follows a specific ______ and ______.

Answer 10

specific pathway and timeline

Question 11

measures of the amount of electrical activity (amplitude) as a function of time.

Answer 11

Auditory evoked potentials

Question 12

Set up to test auditory evoked potentials

Answer 12

Electrodes are placed on the patient’s skull and a receiver (earphone) is seated in the ear canal - you can also use circumaural headphones with electrodes on the ear lobes
The person can be sleeping or in a coma

Question 13

Procedure for testing auditory evoked potentials

Answer 13

A series of brief tones or clicks are presented - the frequency of the click is 1000 Hz and above (it doesn’t measure low frequencies)
The amplitude of the electrical activity that occurs after each stimulus is recorded at each electrode by a computer
Because there is so much electrical activity in the brain, the responses to thousands of stimuli are averaged to find the response common to every stimulus. In this way, random electrical activity is averaged out of the response

Question 14

Auditory evoked potentials is measured in:

Answer 14

epochs (time periods)

Question 15

Epochs for Auditory evoked potentials

Answer 15

Epoch: 0-1.5 ms = electrocochleography (ECoG) - the response comes from the cochlea
Epoch: 1.5-10 ms = Slow latency response (SLR) and Auditory brainstem response (ABR, AEP, BAER)
Epoch: 10-50 ms = middle latency response (MLR)
Epoch: 50-250 ms = late latency response (LLR)

Question 16

the interval of waves from about 1.5-10 ms post stimulus onset

Answer 16

Auditory brainstem response (ABR) - it is the most common evoked potential used clinically

Question 17

The ABR originates in the _____ and extends to the __________

Answer 17

8th cranial nerve; inferior colliculus

Question 18

The exact neural generators of each peak in the waveform:

Answer 18

Wave: Generator:
I Auditory Nerve
II Cochlear Nucleus
III Superior Olivary complex
IV Lateral Lemniscus
V Inferior Colliculus

Question 19

ABR waveform is evaluated in terms of the _______ and the _____ of the individual peaks (waves)

Answer 19

amplitude and latency of the individual peaks/waves

Question 20

In ABR waveforms, amplitude is directly related to the level of the __________ and amplitude increases as _________ increases.

Answer 20

stimulus; level

Question 21

In ABR waveforms, which waves have the highest amplitude and can be seen at lower presentation levels?

Answer 21

Waves III & V

Question 22

the absolute and relative timing of each wave in msec

Answer 22

Latency

Question 23

The absolute latencies are:

Answer 23

Waves I, III, and V

Question 24

the relative latencies are:

Answer 24

Wave I-III, Wave III-V, and Wave I-V (interpeak intervals)

Question 25

Latency is inversely related to the ______________.

Answer 25

Level of the stimulus - as stimulus increases, latency decreases

Question 26

When testing ABR waveforms, the presentation level is _________ until the waves are _________.

Answer 26

reduced incrementally until the waves are no longer visible.

Question 27

In ABR waveforms, the values of the waves are plotted on a graph at latency as a function of ____________.

Answer 27

stimulus intensity (x-axis)
latency (y-axis)

Question 28

Normal wave latencies for adults at 10-20 dB SL:

Answer 28

Wave I: <6.02 msec

Question 29

In ABR waveforms, interwave intervals can be used as diagnostic indices for ______ that affect the auditory brainstem pathway.

Answer 29

otic pathologies

Question 30

Normal interpeak latencies for adults at 10-20 dB SL:

Answer 30

Wave I-III: 2.51 msec
Wave III-V: 2.31 msec
Wave I-V: 4.54 msec

Question 31

Because the latency of the ABR response is related to the intensity of the stimulus, a threshold response can be ________.

Answer 31

estimated - it is sufficient for patients that cannot participate in subjective tests

Question 32

In Auditory Evoked Potentials, how many clicks are reported for?

Answer 32

1500 clicks - but this number can increase if needed

Question 33

The resulting function of an ABR is called a:

Answer 33

latency-intensity function

Question 34

the latency-intensity functions of adults with normal hearing are used to evaluate the results of patients with:

Answer 34

suspected hearing loss