Event-Related Synchronization/Desynchronization for Evaluating Cortical Response Detection Induced by Dynamic Visual Stimuli

Abstract

In the present work, the Event-Related Synchronization and Desynchronization (ERD/ERS) index was used for evaluating the cortical response to dynamic visual stimulation in an postural control protocol. EEG signals (O1, P3, P4 and O2 derivations) of 33 healthy subjects were acquired during stabilometric test. The trials were conducted with the subject observing a white wall (WW) and a virtual scene on static (SS) and dynamic (DS) conditions. The power spectra estimates were compared using the Spectral F-Test (SFT, α = 0.05 and Bonferroni correction) and the ERD/ERS index. The SFT results indicate no difference between the EEG power contribution of WW and SS, and decreased power within alpha band during DS for all derivations. The ERD/ERS index allowed successfully detecting above 83% of the desynchronization within the alpha band during dynamic stimulation. Moreover, it also promotes postural instability. This finding indicates the potentiality of the ERD/ERS technique in studies of postural control assessed by dynamic visual stimulation.