Section of Oral Rehabilitation, Division of Oral Diagnostics and Rehabilitation, Department of Dental Medicine, Karolinska Institutet, Huddinge, Sweden.
Division of Orthodontics, Department of Preventive Dentistry, College of Dentistry, Qassim University, Buraidah, Saudi Arabia.
J Oral Rehabil. 2020 Oct;47(10):1222-1232. doi: 10.1111/joor.13052. Epub 2020 Jul 16.
There are fundamental similarities and differences between the jaw and hand motor systems. However, it is unclear how the two systems respond to unpredictable task demands.
To investigate and compare the force control of the jaw motor system (OMS) and the hand motor system (HMS) during unpredictable load changes.
Seventeen healthy adults (24.0 ± 4.3 years) performed two standardised force control tasks (OMS and HMS). During the OMS, the participants asked to bite and pull a force transducer with the front teeth. While during HMS they pinched and pulled the same force transducer with their index and thumb fingers. Series of loads were added to a string attached to the transducer in an unpredictable (sequential and non-sequential) manner. The entire force profile during the task was divided into "initial" and "latter" segments. The force control was analysed and compared between the OMS and HMS in terms of peak force during the initial segment and holding force and force variability during the latter segment.
The peak force, holding force and force variability were higher for the OMS than the HMS (P < .001). However, there were no differences in the peak force, holding force or force variability between the sequential and non-sequential load changes (P > .05).
The results showed that unpredictable load changes did not affect the force control during the motor control task. This study suggests that both the motor systems are optimised in performing simple motor control tasks and are rather resilient to motor unpredictability.
下颌和手部运动系统之间存在基本的相似性和差异性。然而，尚不清楚这两个系统如何应对不可预测的任务需求。
研究和比较下颌运动系统（OMS）和手部运动系统（HMS）在不可预测的负荷变化下的力控制。
17 名健康成年人（24.0±4.3 岁）完成了两项标准化的力控制任务（OMS 和 HMS）。在 OMS 中，参与者要求用前牙咬住并拉动力传感器。而在 HMS 中，他们用食指和拇指夹住并拉动同一个力传感器。以不可预测的（顺序和非顺序）方式将一系列负荷添加到连接到传感器的字符串上。任务过程中的整个力曲线分为“初始”和“后期”两个部分。分析和比较了 OMS 和 HMS 在初始段的峰值力以及在后期段的保持力和力变异性。
与 HMS 相比，OMS 的峰值力、保持力和力变异性更高（P<.001）。然而，在顺序和非顺序负荷变化之间，峰值力、保持力或力变异性均无差异（P>.05）。
结果表明，不可预测的负荷变化不会影响运动控制任务中的力控制。本研究表明，两种运动系统在执行简单的运动控制任务时都得到了优化，并且对运动的不可预测性具有较强的适应能力。
