Changing heartbeat perception to induce anxiety in virtual environments.

In this paper, we first propose a general technique to induce anxiety in virtual environments (VEs) which exploits auditory heartbeat perception and biofeedback. Then, we consider a VE that reproduces a real-world anxiety-inducing experience (being suddenly surrounded by smoke during a fire evacuation of a building), and we describe an experiment that contrasts 3 conditions: (i) an augmentation of the VE with a bar that indicates when the user's avatar gets hurt, (ii) an augmentation of the VE with the typical audio visual stimuli which are employed in violent videogames when the user's avatar gets hurt, (iii) introduction of the proposed biofeedback technique in the previous condition. We carry out an electrodermal analysis showing that the introduction of the proposed technique produces much higher physiological arousal in terms of skin conductance level (SCL) than the other two conditions. Subjective measures of users' state anxiety are consistent with the recorded physiological reactions.