45天-6°头低位卧床对视觉搜索能力的影响

Effects of 45 d-6° Head-down Bed Rest on Visual Search Ability

目的监测健康成年男性在45 d-6°头低位卧床实验过程中视觉注意搜索能力是否会受到影响。方法 16名男性健康成年受试者进行45 d-6°头低位卧床以模拟失重状态。在卧床前12天、卧床期间(第10,20,30,40天)以及卧床之后第13天进行视觉注意搜索实验。实验一是考察pop-out的被动注意的并行搜索实验,实验二则是考察需要主动注意的串行搜索实验。结果实验一发现受试者的反应时和正确率在几次测试中没有发生显著变化;而实验二受试者的行为表现在测试中逐渐提高,说明发生了知觉学习,其学习过程先快后慢而且逐渐趋于稳定。结论 45 d-6°头低位卧床模拟失重条件下,人的基本视觉搜索能力并没有随着卧床时间的延长而显著变差,视知觉学习能力也仍然存在。

Objective To investigate if the vision search ability of healthy male adults will be influenced by 45 d -6° head-down bed rest（HDBR）. Methods Sixteen healthy male subjects were under 45 d period of -6° HDBR simulated weightlessness state. The vision search ability of participants in -6° HDBR were measured on the 12nd d before, the 13rd d after and on the lOth,20th, 30th, 40th day during the period of HDBR re- spectively. Experiment 1 used the ＂pop-out＂ parallel search stimuli, which was aimed to test the passive at- tention. Experiment 2 was more complicated, in which the serial search stimuli were used to measure the ac- tive attention. Results In experiment 1, the mean accuracy （ ACC ） and reaction time （RT） of participants didn＇ t change significantly during the entire test. While in experiment 2, the performance of those participants improved gradually. It was suggested that they had earned the perceptual learning. At first, the learning process was fast, and then slowed down, showing an obvious tendency to get steady. Conclusion The basic a- bility of visual search is not significantly changed and the visual perceptual learning still exists during 45 d - 6° HDBR simulated weightlessness process.