Detecting sense of presence changes in EEG spectrum during perception of immersive audiovisual content

Quality of Experience (QoE) in multimedia is amply investigated in order to assess the overall acceptability of the content as perceived subjectively by the end user. QoE is usually quantified by self-evaluated subjective scales. However, continuous improvement of signal acquisition, signal processing technologies and increase of computational efficiency enabled the use of physiological signals to evaluate users QoE. In this study the analysis of physiological signals (electroencephalography — EEG) was investigated in order to explore a possibility to evaluate the QoE through the Sense of Presence (SoP). In order to obtain more information about objective QoE evaluation, a dataset of audiovisual stimuli under different SoP was investigated focusing on a relationship between collected subjective assessments and measured physiological signals. Statistical analysis suggests that there exists a relationship between spectral features of EEG and subjective assessment questionnaire results. During investigation, presented in this paper a significant changes in the theta band power was found in all investigated regions. In addition, alpha band activity was shown to change under different levels of the SoP of the frontal, central and occipital lobes. Beta low band activity showed significant changes in the parietal and temporal lobes, beta middle oscillations showed significant differences in the frontal lobe, beta high in temporal lobe. Results revealed that EEG signals can be used as one of the features objectively measuring change of SoP in the immersive audiovisual communications.