Effects of virtual reality visual experience on brain functional network / 生物医学工程学杂志

With the wide application of virtual reality technology and the rapid popularization of virtual reality devices, the problem of brain fatigue caused by prolonged use has attracted wide attention. Sixteen healthy subjects were selected in this study. And electroencephalogram (EEG) signals were acquired synchronously while the subjects watch videos in similar types presented by traditional displayer and virtual reality separately. Two questionnaires were conducted by all subjects to evaluate the state of fatigue before and after the experiment. The mutual correlation method was selected to construct the mutual correlation brain network of EEG signals before and after watching videos in two modes. We also calculated the mutual correlation coefficient matrix and the mutual correlation binary matrix and compared the average of degree, clustering coefficient, path length, global efficiency and small world attribute during two experiments. The results showed that the subjects were easier to get fatigue by watching virtual reality video than watching video presented by traditional displayer in a certain period of time. By comparing the characteristic parameters of brain network before and after watching videos, it was found that the average degree value, the average clustering coefficient, the average global efficiency and the small world attribute decreases while the average path length value increased significantly. In addition, compared to traditional plane video, the characteristic parameters of brain network changed more greatly after watching the virtual reality video with a significant difference ( < 0.05). This study can provide theoretical basis and experimental reference for analyzing and evaluating brain fatigue induced by virtual reality visual experience.

Effects of 24h sleep deprivation on the ability of body balance / 中华行为医学与脑科学杂志

Objective To analyse the efficiency of postural control after 24h sleep deprivation.Methods To observe the change of the static posturography of 16 healthy male after 24h sleep deprivation.Results After 24h sleep deprivation,in both eyes-open condition,whole path length(0h:564.40±42.07,24h:535.23±33.28),unit-path-length(0h:6.96±3.20,24h:5.49±2.65),deflection average center displacement X (0h:7.01±2.79,24h:5.06±3.73)significantly decreased,but standard deviation Y(0h:3.17±0.83,24h:3.98±1.34)significantly increased.In both eyes-closed condition,whole path length(0h:645.70±80.05,24h:587.27±64.87)significantly decreased.Conclusion After 24h sleep deprivation,there are less spontaneous movements of body and lower efficiency of postural control.