Tuning Stressful Experience in Virtual Reality Games

Dynamic game balancing using players’ affective state is a promising approach for creating immersive and engaging video games. We present here the results of StrEx, a system which modulates the stress level induced by a video game in a completely unobtrusive way. It has been tested on an ad-hoc developed Virtual Reality horror-survival game. The system collects motion behavioral data from Head-Mounted Display and its controllers and updates a dynamical model of the player stress level, that takes into account the interior affective state dynamics. Such model is used to guide the transitions of a Finite State Machine that controls the stress level induced by the game, to maintain an appropriate level of stress. The effectiveness of the system has been evaluated through an experimental study in which participants played the game with and without StrEx. Preliminary results show that the StrEx plugin can increase players’ perceived competence and decrease their tension and frustration, thus leading to an increased engagement in the game.