The DC signal of the EEG will be measured with a 10 channel physiological monitoring platform. The electrodes for measuring the surface EEG on the scalp will be snapped in an electrode cap. Besides DC potentials the different classical EEG frequency bands (α,β,θ,δ,) will be monitored in parallel. Other channels of the amplifier will be used for simultaneous recording of the skin conductance level (SC), finger temperature, respiration sensor (monitoring abdominal breathing) and a blood volume pulse sensor (BVP). The parallel monitoring of the peripheral physiological data (SC, BVP, RSP, Temp) give additional information about the present stress level. Heart rate variability can be calculated and monitored from BVP and abdominal respiration rate and displays sympathetic/parasympathetic ratios. Peaks or oscillations in skin conductance level indicate sympathetic predominance of the autonomous nervous system. Monitoring theses individual stress levels is extremely important for the interpretation of the EEG data. On each flight day two subjects will be measured in parallel.
The experiment is a further contribution to basic research concerning the influence of gravity and absence of gravity respectively on fundamental biological processes in human’s central nervous system, including the brain. Furthermore it is conceivable that the experiment is adapted to space flight conditions to investigate the ability of the human brain to adapt to micro gravity on a longer time scale. The results could give further contribution to the field how weak external forces e.g. gravity could influence the excitability of the brain. The control of excitability of the brain is a powerful point of application for therapy of several CNS disorders that are related to excitability of the brain.