What is the best reference electrode in an awake patient with excessive temporal myogenic activity?

The best reference electrode in an awake patient with excessive temporal myogenic activity is the mastoids. The mastoid process is located behind the ears and is an effective site for referencing because it tends to have a low potential for interference from nearby muscle activity, particularly in the temporal region. When excessive myogenic activity is present in the temporal area, using a reference that is close but not directly affected by that muscle activity is crucial.

The mastoids are more distant from the temporal muscles involved than other options, thereby providing a more stable reference point for the EEG readings. This helps in accurately capturing brain activity without the confounding effects of the muscle artifacts generated by facial and temporal muscle movements.

In contrast, options such as ear lobes or the cervical neck region may still pick up some of this myogenic activity, while Cz (central vertex) is generally used for measuring midline activity and may not effectively mitigate the interference from temporal muscle contractions. Therefore, the choice of the mastoids as a reference electrode is appropriate to optimize the quality of the EEG recording in this scenario.