Fowler Barry, Meehan Sean, Singhal Anthony
School of Kinesiology and Health Science, York University, 4700 Keele St., North York, ON, Canada M3J 1P3.
Hum Factors. 2008 Dec;50(6):879-92. doi: 10.1518/001872008X374965.
To determine whether the impairment of perceptual-motor performance often observed during the initial stages of space flight is attributable to the direct effects of microgravity on sensory-motor input-output relationships or to cognitive overload arising from the variety of stressors encountered in this environment.
Experimental evidence is contradictory, and the present experiment investigated the role of two variables: use of ajoystick with tracking or aiming tasks and degree of arm restraint.
Five well-trained astronauts performed Fitts' reciprocal aiming task on three occasions (preflight, on the International Space Station, and postflight) under the following conditions: (a) with a stylus or ajoystick, (b) with the arm restrained or unrestrained, and (c) as a single task or together with auditory reaction time (RT) as a dual task. In addition to the speed and accuracy of responses, kinematic measures were derived from the joystick.
In space, the slope of Fitts' function increased only in the dual task condition with the joystick. RT was also slowed in the dual condition, and there was an increase in aiming and RT errors. Percentage time to peak acceleration, velocity, and deceleration were increased when the aiming task was performed alone.
These results support the cognitive overload rather than the microgravity hypothesis and indicate that an impairment in sensory-motor performance is not a necessary concomitant of space flight.
Impairments in perceptual-motor performance in space can be eliminated or mitigated by appropriate training and task design.
确定在太空飞行初始阶段经常观察到的感知运动能力损伤是归因于微重力对感觉运动输入 - 输出关系的直接影响，还是归因于在这种环境中遇到的各种应激源所引起的认知过载。
实验证据相互矛盾，本实验研究了两个变量的作用：在跟踪或瞄准任务中使用操纵杆以及手臂约束程度。
五名训练有素的宇航员在以下条件下分三次（飞行前、在国际空间站上以及飞行后）执行菲茨往复瞄准任务：（a）使用触控笔或操纵杆，（b）手臂受约束或不受约束，以及（c）作为单一任务或与听觉反应时间（RT）一起作为双重任务。除了反应的速度和准确性外，还从操纵杆获取运动学测量数据。
在太空中，菲茨函数的斜率仅在使用操纵杆的双重任务条件下增加。在双重任务条件下反应时间也变慢，并且瞄准和反应时间误差增加。单独执行瞄准任务时，达到峰值加速度、速度和减速度的时间百分比增加。
这些结果支持认知过载而非微重力假说，并表明感觉运动能力损伤并非太空飞行必然伴随的现象。
通过适当的训练和任务设计，可以消除或减轻太空中感知运动能力的损伤。
