Simulated Spaceflight Operations Under Sleep Deprivation and Confinement

INTRODUCTION: This study investigated how operation complexity and type affect Chinese individuals' performance of simulated spaceflight operations under conditions of sleep deprivation and confinement (SDC). METHODS: There were 20 male volunteers who were randomly divided into 2 groups: the SDC group (N = 8) and the control group (N = 12). During the 72-h experimental period, the volunteers were asked to perform 11 computerized spaceflight emergency procedures, varying in operation complexity and type, three times at the 9th, 33rd, and 57th hours, respectively. Operation times and errors of each spaceflight emergency procedure were recorded. Three complexity levels (i.e., low complexity, high complexity, and combined complexity) and three operation types (i.e., two-way judgment, manual operation, and mixed operation) were identified according to an operation complexity measure and an engineering definition. RESULTS: Mixed model ANOVAs indicated that performance of the three complex operations and three operation types were negatively affected by SDC. Moreover, the results showed that the operation time of the manual operation (12.49 +/- 1.369 at the 33rd hour, 13.27 +/- 2.071 at the 57th hour) and mixed operation (4.88 +/- 0.247 at the 33rd hour, 5.15 +/- 1.308 at the 57th hour) increased significantly with the increase of waking time. It was also shown that the high complexity operation and manual operation got less variation in operation time compared with low complexity and two-way judgment, respectively. CONCLUSIONS: The result indicated that the task assignment with high complexity requiring cognition could be a useful way to counteract the effect of SDC. It was also implied that psychomotor abilities were more easily affected by SDC than perception and judgment.