کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
4313457 | 1289998 | 2012 | 7 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Increased occlusal vertical dimension induces cortical plasticity in the rat face primary motor cortex Increased occlusal vertical dimension induces cortical plasticity in the rat face primary motor cortex](/preview/png/4313457.png)
Previous studies have demonstrated that functional plasticity in the primary motor cortex (M1) is related to motor-skill learning and changes in the environment. Increased occlusal vertical dimension (iOVD) may modulate mastication, such as in the masticatory cycle, and the firing properties of jaw-muscle spindles. However, little is known about the changes in motor representation within the face primary motor cortex (face-M1) after iOVD. The purpose of the present study was to determine the effect of iOVD on the face-M1 using intracortical microstimulation (ICMS). In an iOVD group, the maxillary molars were built-up by 2 mm with acrylic. The electromyographic (EMG) activities from the left (LAD) and right (RAD) anterior digastric (AD), masseter and genioglossus (GG) muscles elicited by ICMS within the right face-M1 were recorded 1, 2 and 8 weeks after iOVD. IOVD was associated with a significant increase in the number of sites within the face-M1 from which ICMS evoked LAD and/or GG EMG activities, as well as a lateral shift in the center of gravity of the RAD and LAD muscles at 1 and 2 weeks, but not at 8 weeks. These findings suggest that a time-dependent neuroplastic change within the rat face-M1 occurs in association with iOVD. This may be related to the animal's ability to adapt to a change in the oral environment.
► The effect of occlusal change was investigated using intracortical microstimulation.
► Number of positive sites increased at 1 and 2 weeks, but not at 8 weeks.
► Neuroplastic changes appeared to reflect adaptation of the central nervous system.
Journal: Behavioural Brain Research - Volume 228, Issue 2, 17 March 2012, Pages 254–260