Comparison of Electroencephalogram (EEG) Power Spectra Between Non-Vection and Vection

Previous studies showed that when subjects were exposed to a vection-evoking stimulus, there were significant differences in EEG readouts. But the control stimuli they used were different from the experiment stimuli, and whether the subjects truly experienced vection was not examined. This study aimed to record the brain signals when subjects actually experience vection and to determine the differences in signaling between non-vection and vection in EEG power spectra. Ten subjects were asked to watch a grating stimulus to induce vection, while simultaneously their EEG signals were measured. According to the subjective judgement, the whole EEG signals were divided into a non-vection part and a vection part. The mean values of the log of the power spectra in different bands were analyzed by a paired t test. The delta band showed a significant difference between non-vection and vection on almost all leads. Obvious changes in the theta and alpha band were in the frontal and temporal regions of the brain. However, there were no significant changes in the beta and gamma bands. In conclusion, statistically significant differences were found in the power spectra of the EEG between non-vection and vection for some leads, especially for the slow waves. This study provides some evidence to back up the sensory conflict hypothesis of vection, and can help to discriminate not only vection and non-vection phase, but also vection and visual motion sickness.