Tension in the Two Frontales: Electrode Placement and Artifact in the Recording of Forehead EMG.

The conventional placement of electrodes for recording forehead, or "frontalis" EMG attenuates forehead potentials by placing one electrode over each frontalis muscle. The placement also precludes exploration of differences in the activity of the two muscles, and is influenced by potentials arising in nearby muscles. An alternative unilateral bipolar lead placement is suggested and demonstrated. [ABSTRACT FROM AUTHOR]