View source for Brainstem Auditory Evoked Responses (BAER)

==Introduction==
Auditory evoked potentials are critical for monitoring the integrity of the brainstem and cortex. BAERs are a series of positive and negative waveforms that arise from neural structures associated with the ascending auditory pathway, including the cochlea, brainstem, and auditory cortex. Short latency BAERs (< 10 ms) are used to monitor brainstem function, whereas long‐latency BAERs (> 10 ms) are used to monitor cortical function.

==Auditory pathways==
When sound enters the ear, the sensory information is first transduced by the receptors in the cochlea (inner ear). The cochlea is composed of fluid-filled compartments separated by membranes. The membranes express hair cells that are 'tuned' to a particular frequency. Sufficient movement of the hair cells will depolarize individual fibers of the auditory portion of the VIII cranial nerve. There are inner and outer hair cells; the inner hair cells are involved in signal transduction and can connect to multiple axons of the auditory nerve.

==Stimulation==
In the clinical setting, action potentials generated by the auditory nerve are elicited by click sounds or a tone burst.

==Recording Techniques==

==Waveform==
There are different types of electric potentials with varying inter-peak latencies. Each peak represents the activity of a specific neural generator. For example, the cochlea generates cochlear microphonics and summating potentials.

#Peaks and neural generators
#Latencies and interpeak latencies
#Normal values

==Intraoperative monitoring==


==References ==