The study analyzed the intersubject synchronization of bioelectrical brain activity among the audience during a fairy tale theatrical performance. The study examines synchronization between participants without external stimulus synchronization (i.e., without evoked potentials). The electroencephalographic (EEG) data were synchronized using specialized technical signals that didn’t attract the participants’ attention and were used solely to ensure precise temporal alignment of EEG fragments across different stages of the performance. The EEG data were analyzed both individually and in pairs. Individual analysis assessed EEG spectral power at rest before and after the performance, as well as at different stages of performance in Δ (1.5–4 Hz)-, θ (4–8 Hz)-, α1 (8–10 Hz)-, α2 (10–13 Hz)-, β1 (13–18 Hz)-, and β2 (18–30 Hz)-frequency bands. Pairwise analysis (21 pairs, where all participants were paired with each other) evaluated phase locking value (PLV) and circular correlation coefficient (CCorr). No differences in baseline spectral power (pre- vs. post-performance) were detected, suggesting an absence of viewers’ fatigue. However, a decrease of the EEG spectral power was observed in the α1- and α2-frequency bands, potentially connected with viewer engagement, selective attention, emotional and aesthetic experience, and emotional immersion in the narrative, needed for its perception and comprehension. Intersubject synchronization metrics (both PLV and CCorr) revealed increased synchronization in θ-, α1-, and α2-bands over central-parietal-occipital regions, coupled with reduced frontal region synchronization (relative to artificially generated data) pronounced during the second stage of performance. This likely corresponded to the plot culmination point.
Zavodova et al. (2025) studied this question.