What is the physiologic basis of auditory evoked potentials (BAEPs)?

Updated: Oct 25, 2019
  • Author: Andrew B Evans, MD; Chief Editor: Selim R Benbadis, MD  more...
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BAEPs predominantly activate the pathways in the brainstem that are ipsilateral to the side of click stimulation. In particular, lesions in the middle to upper pons tend to lead to ipsilateral BAEP abnormalities. The structures involved in the generation of BAEPs may be concerned more with sound localization than with hearing itself.

Whether nuclei, tracts, or both generate the peak latencies is not known. Currently, the generators are postulated to be as follows:

  • Wave I - Action potential of cranial nerve (CN) VIII

  • Wave II - Cochlear nucleus (and CN VIII)

  • Wave III - Ipsilateral superior olivary nucleus

  • Wave IV - Nucleus or axons of lateral lemniscus

  • Wave V - Inferior colliculus

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