Live vs Video Interaction: Sensorimotor and Visual Cortical Oscillations During Action Observation

Increasingly, in the field of communication, education and business, people are switching to video interaction, and interlocutors frequently complain that the perception of non-verbal information and concentration suffer. We investigated this issue by analyzing EEG oscillations of the sensorimotor (mu-rhythm) and visual (alpha-rhythm) cortex of the brain in an experiment with observation of identical action demonstrators live and on video. The mu-rhythm reflects the activity of the mirror neuron system, which is responsible for social perception of the actions and body language of other people, and the occipital alpha-rhythm shows the level of visual attention. We used 32-channel EEG recorded during live and video action observation in 83 healthy volunteers. The ICA infomax method was used for decomposing and selecting the components of the mu- and alpha-rhythms; the Fourier Transform was used to calculate the suppression index relative to the baseline (stationary demonstrator) of the two sub-bands (8-13 Hz and 13-24 Hz) of the mu-rhythm and the alpha-rhythm. Our work shows that the main range, 8-13 Hz, of the mu-rhythm is indeed sensitive to biological and social movement and is highly dependent on the conditions of interaction - live or video. The upper mu-range of 13-24 Hz appeared to be less sensitive to the type of demonstration, but more sensitive to different movements. The alpha-rhythm does not depend on the type of movement, however, a live performance initially causes a stronger concentration of visual attention. Thus, subtle social and nonverbal perceptions may suffer in remote video interactions.