Characteristics of event related potentials elicited by trains of teeth clenching in humans

Event related potentials were recorded on the human scalp during a foot pedal task, a hand gripping task, and a teeth clenching task. These were carried by targeting four trains of clicks, each at an interval of 1 sec, which were repeated 20 times at random frequencies. The brain potentials were recorded from midline-frontal (Fz), -central (Cz) and -parietal (Pz) sites using surface electrodes. Positive potentials like P3 were elicited predominantly at the frontal site (Fz); those for the clenching task were slower and smaller. The magnitudes of the P3 potentials showed rough facilitation with trains of movement of the tasks. If it is assumed that the observed potentials involve an inhibition or reset of motor neurons referring to the tasks, the facilitation might be expedient for the neurons to recover the potential condition more quickly, which is important in preparing for the next action.