title: [Effect of head-down bed rest on human EEG].
abstract: Objective. To study the influences of short-term simulated weightlessness on human EEG. Method. EEG of 12 male subjects (aged 18-22) was recorded, pre-HDBR (-6 degrees head down bed rest), mid-HDBR (3rd, 4th, 6th day) and post-HDBR (3rd day). Then these EEG recordings were analyzed by power spectral analysis. Result. During HDBR, peak frequency of EEG gradually slowed down (6th day, P<0.05). Alpha-band activities were enhanced (alpha1: P<0.001. Alpha2: 3rd and 6th day, P<0.05; 4th day, P<0.001) and reached maximum on the 4th day. Alpha1/alpha2 ascended (6th day, C3 and C4: p<0.02; F4, P4, T3, T4, T5: P<0.05). Theta-band activities enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions, on the 4th day at parieto-occipital regions. Theta/alpha ascended obviously (6th day, P3, O1: P<0.05). Meanwhile, beta1, activities also enhanced (P<0.001), and reached maximum on the 3rd day at frontal regions. After HDBR, the index that recovered to the pre-HDBR level first was EEG peak frequency. Conclusion. HDBR caused obvious changes of EEG power spectrum characteristic. There exists a potential influence on brain function.
authors.affiliation: Institute of Space Medico-Engineering, Beijing, China.
authors.forename: D X
authors.initials: DX
authors.lastname: Han
authors.forename: Y H
authors.initials: YH
authors.lastname: Liu
authors.forename: C D
authors.initials: CD
authors.lastname: Zhou
authors.forename: B L
authors.initials: BL
authors.lastname: Zhang
authors.forename: J X
authors.initials: JX
authors.lastname: Fei
authors.forename: G
authors.initials: G
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000328:Adult; D001510:Bed Rest; D001921:Brain / Q000502:physiology; D004569:Electroencephalography; D018475:Head-Down Tilt; D006801:Humans; D008297:Male; D018474:Weightlessness Simulation