Effect of fluid motion on movement performance and finger-force pattern during manipulation of Containers/Cups filled with Liquid

Abstract

The purposes of this study were to: 1) evaluate how movement performance of the thumb and fingers were modified during manipulation of objects with and without fluids and 2) to quantify movement performance and accuracy during manipulation of objects, in two different modes of manipulation, i.e., pendulum and inverted pendulum. Twenty young healthy adults (age 24-35) were recruited and performed two predictable cyclic tracking tasks and episodic short-duration precision movement task. No change in movement performance observed in open-loop or episodic tasks. However, in closed-loop task, mode of manipulation (IP versus P) had a significant effect on amplitude consistency (P<0.001), and temporal accuracy (P<0.050).Fluid motion had a significant effect on RMS of index finger contact forces (p < 0.01) in episodic task. In conclusion, fluid motion had no significant effect on movement performance and accuracy. The quality of movement was better in pendulum mode than inverted pendulum movement.