Interacoustics Eclipse ABRIS, Instructions For Use Manual, Page: 64 / 149

D-0120588-B
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2019/03
Eclipse
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Instructions for Use - EN Page 56
3.13 Making a P300/MMN recording
P300 and MMN (mismatch negativity) can be used for evaluation of the auditory function.
The MMN test is particular related to the brain ability to discriminate between speech sounds.
MMN is elicited with an oddball paradigm in which infrequent occurring deviant sounds are embedded in a
series of frequency occurring standard sounds.
The duration of P300/MMN stimuli are much longer compared to traditional ABR stimuli.
3.13.1 Example of electrode montage for P300/MMN
RED Right mastoid or ear lobe (reference or inverting)
BLUE Left mastoid or earlobe (reference or inverting)
It is advised to jumper Red and Blue electrode to establish an averaged reference.
WHITE True CZ (active or non inverting)
BLACK Ground at cheek or low forehead - distance of few cm to WHITE electrode must be observed.
The arousal state/Patient attention of the patient has an effect on the amplitudes of the MMN response.
MMN can also be elicited when the subject pay attention to stimuli, but it is difficult to measure in this condition
because of the overlap from the N
21
component.
As a result it is recommended that MMN to be recorded while the subject ignores the stimuli and read or watch
a silent captioned video and not to pay attention to the stimuli.
MMN amplitudes decrease with increased sleepiness and in sleep.
It is not advised to perform P300/MMN under sedation.
The P300/MMN latency ranges from -100-500ms and amplitude sizes ranges from 0-20uV.
3.13.2 Available P300/MMN stimuli
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Tone bursts 250 Hz
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4 kHz
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NB CE-Chirp ® and NB CE-Chirp ® LS 500 Hz, 1 kHz, 2 kHz and 4 kHz
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Custom WAV file (when Research Module license is enabled)