Influences of daily stress upon spatial orientation

【对象与方法】为了研究疲劳对空间定向功能的影响，我们让10名青年志愿者（男6名，女4名，平均年龄21.4岁）整夜不睡，记录他们的身体摆动，并在第二天早上测试他们的心算能力。这些发现与充分睡眠后的结果进行了比较。实验在获得所有受试者的知情同意后进行。【结果】静息时记录的3分钟压心痕迹平均总长度为：酣睡后为193.6±18.1 cm，熬夜后为218±20.0 cm。平均身体摇摆面积分别为4.71±0.91 cm^2和6.60±1.18 cm^2。当被试以60°/s旋转记录身体摆动时，压力中心轨迹的平均总长度分别为632.7±69.0 cm和678.4±106.5 cm，平均身体摆动面积分别为24.82±4.71 cm^2和36.35±10.81 cm^2。所有这些结果在良好睡眠状态和熬夜状态之间没有显著差异。心算能力在两组之间也没有显著差异。主诉眩晕或头晕的病人常感到疲劳和睡眠不足。为了了解脑衰竭对身体平衡和心理活动的影响，我们对年轻的正常志愿者进行了本研究。身体平衡能力和心算能力不受熬夜的影响。虽然我们已经调查了通宵工作对应激标志物（如血浆抗利尿激素、类固醇激素和血浆纤维蛋白原）的影响，但通宵工作后未发现任何统计学差异。一个人熬夜似乎不会损害大脑功能。

【Subjects and methods】 To investigate influences of fatigue upon spatial orientation function, we made 10 young volunteers (6 male and 4 females, mean age of 21.4 years) stay up all night, and recorded body sways and examined abilities of mental arithmetic next morning. These findings were compared to the results examined after sound sleep. Experiments were performed after obtaining informed consents from all subjects.【Results】 Mean total lengths of traces of the center of pressure for 3 minutes, when recorded while subjects were standstill, were 193.6±18.1 cm after sound sleep, and 218±20.0 after staying up all night. Mean areas of body sway were 4.71±0.91 cm^2, and 6.60±1.18 cm^2, respectively. When body sways were recorded while the subjects were rotated at 60 deg/s, mean total lengths of traces of the center of pressure were 632.7±69.0 cm and 678.4±106.5 cm, and mean areas of body sway were 24.82±4.71 cm^2 and 36.35±10.81 cm^2, respectively. All these findings did not significantly differ between the sound sleep condition and the staying up all night condition. The ability of mental arithmetic also did not show any significant difference between two conditions.【Discussion】 Fatigue and lack of sleep are often found in patients who complain of vertigo or dizziness. In order to know the influence of brain exhaustion upon body balance and mental activity, we performed the present study on young normal volunteers. Both abilities of body balance and mental arithmetic were not influenced by staying up all night. Although we have investigated influences of working all night upon stress markers such as plasma vasopressin, steroid hormones, and plasma fibrinogen, any statistical difference has not been found after working all night. Staying up all night alone may not seem to deteriorate brain functions.