Service de Physique de l'Univers, Champs et Gravitation, Université de Mons, UMONS Research Institute for Complex Systems, Place du Parc 20, 7000 Mons, Belgium.
CeREF, Chaussée de Binche 159, 7000 Mons, Belgium.
Phys Rev E. 2020 Dec;102(6-1):062403. doi: 10.1103/PhysRevE.102.062403.
Voluntary human movements are stereotyped. When modeled in the framework of classical mechanics they are expected to minimize cost functions that may include energy, a natural candidate from a physiological point of view also. In time-changing environments, however, energy is no longer conserved-regardless of frictional energy dissipation-and it is therefore not the preferred candidate for any cost function able to describe the subsequent changes in motor strategies. Adiabatic invariants are known to be relevant observables in such systems, although they still need to be investigated in human motor control. We fill this gap and show that the theory of adiabatic invariants provides an accurate description of how human participants modify a voluntary, rhythmic, one-dimensional motion of the forearm in response to variable gravity (from 1 to 3g). Our findings suggest that adiabatic invariants may reveal generic hidden constraints ruling human motion in time-changing gravity.
自主运动是刻板的。当在经典力学框架中对其进行建模时，预计会最小化成本函数，这些函数可能包括能量，从生理学角度来看，能量也是一个自然的候选者。然而，在时变环境中，能量不再守恒——无论摩擦能量耗散如何——因此，它不是任何能够描述后续运动策略变化的成本函数的首选候选者。绝热不变量已知是此类系统中的相关可观测量，尽管它们仍需要在人类运动控制中进行研究。我们填补了这一空白，并表明绝热不变量理论能够准确描述人类参与者如何根据可变重力（从 1g 到 3g）来修改自主、有节奏的一维前臂运动。我们的研究结果表明，绝热不变量可能揭示了在时变重力下支配人类运动的通用隐藏约束。
