Effects of electrode movements on masseteric electromyograms of teeth clenching in humans.
In six healthy subjects, the integrated electromyographic (IEMG) activity of the right masseter muscle was recorded during 10 s of maximum voluntary teeth clenching, without and with manual movements (at a rate of 1.6 Hz, with a force of approximately 3N) of the bipolar surface electrodes affixed to the cheek. All IEMG recordings were undertaken at discrimination thresholds of 1 microV and 30 microV. Electrode movements were the likely source of some distortion (artefact) of the IEMG readings. An increase in the discrimination threshold (30 microV vs. 1 microV) seemed to decrease the artefactual effects of electrode movements, possibly because the movements exerted their major distorting effects on the smaller (low voltages) masseteric motor units.
Christensen
L V
LV
Marquette University, School of Dentistry, Milwaukee, Wisconsin, USA.
D000328:Adult; D016477:Artifacts; D001732:Bite Force; D004566:Electrodes; D004576:Electromyography / Q000295:instrumentation* / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008406:Masseter Muscle / Q000502:physiology*; D009119:Muscle Contraction; D011999:Recruitment, Neurophysiological; D015203:Reproducibility of Results