A Virtual Reality Game as a Tool to Assess Physiological Correlations of Stress

The objective of this study is to develop and use a virtual reality game as a tool to assess the effects of realistic stress on the behavioral and physiological responses of participants. The game is based on a popular Steam game called Keep Talking Nobody Explodes, where the player collaborates with another person to defuse a bomb. Varying levels of difficulties in solving a puzzle and time pressures will result in different stress levels that can be measured in terms of errors, response time lengths, and other physiological measurements. The game was developed using 3D programming tools including Blender and virtual reality development kit (VRTK). To measure response times accurately, we added LSL (Lab Stream Layer) Markers to collect and synchronize physiological signals, behavioral data, and the timing of game events. We recorded Electrocardiogram (ECG) data during gameplay to assess heart rate and heart-rate variability (HRV) that have been shown as reliable indicators of stress. Our empirical results showed that heart rate increased significantly while HRV reduced significantly when the participants under high stress, which are consistent with the prior mainstream stress research. We further experimented with other tools to enhance communication between two players under adverse conditions and found that an automatic speech recognition software effectively enhanced the communication between the players by displaying keywords into the player's headset that lead to the facilitation of finding the solution of the puzzles or modules. This VR game framework is publicly available in Github and allows researchers to measure and synchronize other physiological signals such as electroencephalogram, electromyogram, and pupillometry.