Abstract
The effects of bilateral experimental muscle pain on human masticatory patterns were studied. Jaw movements and electromyographic (EMG) recordings of the jaw-closing muscles were divided into multiple single masticatory cycles and analyzed on a cycle-by-cycle basis. In ten men simultaneous bilateral injections of hypertonic saline (5%) into the masseter muscles caused strong pain (mean±SE: 7.5±0.4 on a 0–10 scale), significantly reduced EMG activity of jaw-closing muscles in the agonist phase, and significantly increased EMG activity in the antagonist phase. Nine of the subjects reported a sensation of less intense mastication during pain. Injections of isotonic saline (0.9%) did not cause pain or significant changes in masticatory patterns. The influence of higher brain centers on conscious human mastication can not be discarded but the observed phase-dependent modulation could be controlled by local neural circuits and/or a central pattern generator in the brain stem which are capable of integrating bilateral nociceptive afferent activity.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 19 February 1997 / Accepted: 14 April 1997
Rights and permissions
About this article
Cite this article
Svensson, P., Houe, L. & Arendt-Nielsen, L. Bilateral experimental muscle pain changes electromyographic activity of human jaw-closing muscles during mastication. Exp Brain Res 116, 182–185 (1997). https://doi.org/10.1007/PL00005738
Issue Date:
DOI: https://doi.org/10.1007/PL00005738