CONSTRUCTION AND ANALYSIS OF WEIGHTED BRAIN FUNCTIONAL NETWORK BASED ON APPROXIMATE ENTROPY OF ELECTROENCEPHALOGRAPHY UNDER MAGNETIC STIMULATION AT NEIGUAN ACUPOINT

摘要

The study of brain functional network can help to explore the working mechanism of brain. Compared with un-weighted network, weighted network is better to reflect the real connection strength among vertices. This study aims at investigating the therapeutic mechanism of acupuncture through analysing the weighted brain functional network under magnetic stimulation at Neiguan (PC6) acupoint. In this study, electroencephalograph (EEG) signals were recorded under quiescent, stimulated and post-stimulated states; weighted brain functional networks were constructed based on approximate entropy (ApEn) and mutual information theory; topological features of the networks were comparatively analysed among the three states by using complex network theory. The experimental results show that the average degree, average clustering coefficient and global efficiency of networks at stimulated state and post-stimulated state are increased compared to the quiescent state. These results indicate that the networks connection strength are enhanced, clique level are improved, information transmission efficiency are increased through stimulating PC6 acupoint. The topological features at post-stimulated state show decreasing trends compared to the stimulated state except for partial metrics of a few subjects remain unchanged, moreover, the reduction among subjects are different. These phenomena are considered to be related with individual difference and cumulative effect of stimulation.