Canonical Correlation Analysis Based Correlation Research Between EEG And Physiology, Psychology In Microgravity

During space flight, brain plays an important control for an astronaut to adapt to space environment, and adjust the physiological and psychological reaction. The disturbance of brain may cause the dysfunction of control and regulation, affect the fitness of astronauts and even hinder the completion of space mission. In the aerospace medicine field, the results of brain functional research reveal that microgravity or simulated microgravity may affect central nervous electrical activity, possibly through physiological or psychological ways. However, the multimodality and insufficient integration of data render most above results from indirect inference, rather than directly from the correlation analysis between data sets.Under this background, canonical correlation analysis (CCA) method is introduced to analyze the correlation between EEG variations and other physiological or psychological changes in our study. Within the context of actual application, a two-level CCA based model is proposed, based on the combination of CCA and multilevel statistical model. In consideration of the favorable applicability for heterogeneous data of CCA method, the correlations between cardiovascular, mood and cognition with EEG was measured under-6degree head down bed rest. Using the distribution of electrodes, the cardiovascular and cognitive dysfunction induced EEG changes are localized in specific cortical region according to the20electrodes position. The K Nearest Neighbor (KNN) classifier was adopted to verify the validity of the CCA based model.The CCA model analysis results show that the EEG, cardiovascular, mood state and cognitive performance all present impairment to certain extent during the bed rest period. The cardiovascular effect mainly correlates EEG changes in bilateral temporal region and the cognitive effect correlates parietal-occipital and frontal regions. Emotion related cognitive deterioration is related to parietal-occipital region. Basic cognitive ability and spatial attentional cogntion are related to frontal region.