Auditory brainstem response Questions and Correct Answers 2024

What are some common names for ABR? - Brainstem Evoked Response (BER), Brainstem Auditory Evoked Potential (BAER) Is ABR near or far field? - Far Is ABR a mesogenous, exogenous, or endogenous response? - EXogenous The ABR is comprised of _____ waves (peaks) which are denoted by _______ - 6-7 roman numerals The ABR is measured with in the first _______ msec relative to stim onset - 12 msec The response for the ABR is ______ locked - time locked, the response is tied to stimulus timing Generally speaking, your waves are going to be about _____ msec apart - 1 msec What is the generator of Wave I of the ABR? - the peripheral portion of the 8th nerve (it's the same thing as the AP of the ECoG) What is the generator of Wave II of the ABR? - The central portion of the 8th Nerve (if they have a Wave II) What is the generator of Wave III of the ABR? - Postsynaptic Potentials of the Cochlear Nucleus The Postsynaptic potentials in the cochlear nucleus is where the _________ order neurons synapse to the _________ order neurons. - first order neurons, second order neurons What is the space between Wave II and III generators and why is it important? - It is called the cerebellopontine angle and it is a very common site for tumor growth What will a tumor in the cerebellopontine angle cause? - A gap in the reading from Wave I and III even though the generator location is between II and III Wave IV is the synapse between what and what? - Second and third order neurons What is the Wave V generator and the order neurons involved? - Lateral Lemniscus (some people would say that the inferior colliculus is involved too) the connection of 3rd and 4th order neurons What is the generator of Wave VI? - It is the termination of the lateral lemniscus and the inferior colliculus, it is the synapse between the 4th and 5th order neurons. IF someone has a Wave VII, what is the generator? - The inferior colliculus to the medial geniculate body (5th and 6th order neurons) Various peaks of the ABR are likely produced by - stationary dipoles Waves I and III are generated by ________________ dipoles - horizontal Waves IV and V are generated by ____________ diapoles - vertical Anything after Wave IV is what direction of dipole? - Vertical If you know the direction of your dipole, you can decide the best what to use? - Montage, certain montages will enhance certain waves and diminish others. We almost always do vertical montages.