Journal of Neurophysiology, Vol 68, Issue 3 933-944, Copyright © 1992 by APS

ARTICLES

Control of elevator muscle activity during simulated chewing with varying food resistance in humans

F. A. Ottenhoff, A. van der Bilt, H. W. van der Glas and F. Bosman
Department of Oral Pathophysiology, Faculty of Medicine, University of Utrecht, The Netherlands.

1. During chewing, a small part of the observed muscle activity is needed for the basic open-close movements of the mandible, and much additional muscle activity (AMA) is needed to overcome the resistance of the food. In chewing cycles in which a counteracting force is expected, the AMA is mainly generated by peripheral induction with a latency of approximately 23 ms. It was investigated whether an open-loop or closed-loop mechanism is involved in the control of the AMA in these cycles. 2. Subjects made rhythmic open-close movements at their natural chewing frequency controlled by a metronome. Food resistance was simulated by an external force, acting on the jaw in a downward direction during part of the closing movement. Sequences of cycles with a force were unexpectedly alternated with sequences of cycles with a different force. The force changed from 19 to 0 N and vice versa, and from 25 to 6 N and vice versa. Jaw movement and surface electromyogram of the masseter, temporalis, and suprahyoid muscles on both sides were recorded during cycles before and after the transition from one force condition to another. 3. The movement trajectory and AMA of the second and following cycles with a new force appeared to be similar. Thus adaptation to the changed circumstances occurred within two open-close cycles. 4. In the first cycle with 0 or 6 N in the 19----0 N and 25----6 N experiments respectively, a large part of the AMA had disappeared. The AMA in this cycle started to differ from the AMA in the previous cycle approximately 23 ms after the moment the force in this cycle started to differ from the previous cycle. 5. In the first cycle with 19 or 25 N in the reverse experiments, the AMA increased 120-136 ms after the moment the force in this cycle started to differ from the previous cycle. 6. During the closing phase of each open-close cycle, no muscle activity of the suprahyoid muscles was observed; thus co-contraction with the elevator muscles did not occur. 7. It was concluded that the AMA is under control of a closed-loop mechanism with a latency of approximately 23 ms. However, the reflex output has a maximum, depending on information about the food resistance gained in previous cycles.(ABSTRACT TRUNCATED AT 400 WORDS)

This article has been cited by other articles:

				C. F. Ross, A. Eckhardt, A. Herrel, W. L. Hylander, K. A. Metzger, V. Schaerlaeken, R. L. Washington, and S. H. Williams Modulation of intra-oral processing in mammals and lepidosaurs Integr. Comp. Biol., July 1, 2007; 47(1): 118 - 136. [Abstract] [Full Text] [PDF]

				C. F. Ross, R. Dharia, S. W. Herring, W. L. Hylander, Z.-J. Liu, K. L. Rafferty, M. J. Ravosa, and S. H. Williams Modulation of mandibular loading and bite force in mammals during mastication J. Exp. Biol., March 15, 2007; 210(6): 1046 - 1063. [Abstract] [Full Text] [PDF]

				K. D. Foster, A. Woda, and M. A. Peyron Effect of Texture of Plastic and Elastic Model Foods on the Parameters of Mastication J Neurophysiol, June 1, 2006; 95(6): 3469 - 3479. [Abstract] [Full Text] [PDF]

				S. E. Johnsen and M. Trulsson Encoding of Amplitude and Rate of Tooth Loads by Human Periodontal Afferents From Premolar and Molar Teeth J Neurophysiol, April 1, 2005; 93(4): 1889 - 1897. [Abstract] [Full Text] [PDF]

				E. Neyraud, M.A. Peyron, C. Vieira, and E. Dransfield Influence of Bitter Taste on Mastication Pattern J. Dent. Res., March 1, 2005; 84(3): 250 - 254. [Abstract] [Full Text] [PDF]

				B. Haggman-Henrikson and P.-O. Eriksson Head Movements during Chewing: Relation to Size and Texture of Bolus J. Dent. Res., November 1, 2004; 83(11): 864 - 868. [Abstract] [Full Text] [PDF]

				T. S. Miles, S. C. Flavel, and M. A. Nordstrom Control of human mandibular posture during locomotion J. Physiol., January 1, 2004; 554(1): 216 - 226. [Abstract] [Full Text] [PDF]

				K. S. Turker REFLEX CONTROL OF HUMAN JAW MUSCLES Crit. Rev. Oral. Biol. Med., January 1, 2002; 13(1): 85 - 104. [Abstract] [Full Text] [PDF]

				A. Komuro, T. Morimoto, K. Iwata, T. Inoue, Y. Masuda, T. Kato, and O. Hidaka Putative Feed-Forward Control of Jaw-Closing Muscle Activity During Rhythmic Jaw Movements in the Anesthetized Rabbit J Neurophysiol, December 1, 2001; 86(6): 2834 - 2844. [Abstract] [Full Text] [PDF]

				G. E. J. Langenbach and T. M. G. J. van Eijden Mammalian Feeding Motor Patterns Integr. Comp. Biol., December 1, 2001; 41(6): 1338 - 1351. [Abstract] [Full Text] [PDF]

				K. S. Turker and M. Jenkins Reflex Responses Induced by Tooth Unloading J Neurophysiol, August 1, 2000; 84(2): 1088 - 1092. [Abstract] [Full Text] [PDF]

				O. Hidaka, T. Morimoto, Y. Masuda, T. Kato, R. Matsuo, T. Inoue, M. Kobayashi, and K. Takada Regulation of Masticatory Force During Cortically Induced Rhythmic Jaw Movements in the Anesthetized Rabbit J Neurophysiol, June 1, 1997; 77(6): 3168 - 3179. [Abstract] [Full Text] [PDF]