Which electrode is used as the active electrode for BAEP Wave 1?

In the context of Brainstem Auditory Evoked Potentials (BAEP) testing, Wave 1 is primarily generated by the auditory nerve and is typically represented by signals received from the cochlear nucleus. The active electrode plays a crucial role in capturing the electrical activity from the neural sites of interest.

The use of the Aipsi (or the 'active ipsilateral') electrode means that it is placed on the same side as the stimulus being presented. This placement is significant because it ensures optimal signal acquisition from the pathway that is directly involved in the auditory processing initiated by the stimulus. The Aipsi electrode is designed to enhance the detection of the first wave (Wave 1) of the BAEP by picking up the corresponding neural signals more clearly.

When considering the other potential electrodes:

• A1, which is an electrode typically placed on the left ear, may not adequately represent the activity related to the ipsilateral ear's stimulus.

• Cz, located at the vertex of the skull, often serves as a reference point or return electrode rather than an active electrode for specific waveform identification.

• Aipsi-t usually indicates a combination of active and reference, which does not optimally capture the same direct signals as Aipsi.

Thus,