Taking the perspective of an embodied avatar modulates the temporal dynamics of vicarious pain and pleasure: a combined Immersive Virtual Reality and EEG study

Abstract

AbstractObserving negative and positive valence virtual stimuli can influence the onlookers’ subjective and brain reactivity. However, information about the complex link between vicarious pain and pleasure, observer’s perspective taking, and cerebral activity is scarce. To address this knowledge gap, we asked twenty-four, VR-immersed healthy participants to report about pleasant, painful, and neutral stimuli delivered to a virtual hand seen from either a first-person perspective (1PP) or third-person perspective (3PP) while undergoing time and time-frequency EEG recording. Participants experienced a stronger sense of ownership over a virtual hand when they viewed it from a 1PP compared to a 3PP. Furthermore, participants rated pain-inducing and pleasure-inducing stimuli as most unpleasant and pleasant, and as more intense. We observed distinct EEG patterns in early (N2, early posterior negativity- EPN) and late (late positive potential-LPP) event-related potentials, as well as in EEG power. The N2 and EPN components showed higher amplitudes for pain and pleasure stimuli compared to neutral stimuli particularly when seen from a 1PP. Conversely, the LPP component exhibited a smaller amplitude for pleasure stimuli compared to both pain and neutral stimuli. We also found that theta-band power increased and alpha power decreased for pain and pleasure stimuli viewed from a 1PP vs a 3PP perspective. Also, in the ultra-late time-window, we observed a decrease in theta, alpha, and beta-band power specifically associated with pleasure stimuli. Our study provides novel evidence on how perspective taking influences the temporal dynamics of vicarious sensations and on distinct electrocortical markers of observed pain and pleasure.