Psychophysiological interaction offers the opportunity of delivering unique and innovative experiences that synergize with human physiological and psychological nature. Even though several publications have explored the use of psychophysiological interaction in video games in the past, there is still a set of challenges associated with its suitability for commercial entertainment games, and with the assessment of its relationship with the perceived player experience.

This dissertation explores psychophysiological interaction and its implementation within entertainment video games. It presents a review of multiple physiological methods, such as eye tracking, electrodermal activity, or electroencephalography, and discusses the possibilities and challenges that these methodologies offer for the design and implementation of natural user interaction techniques. The dissertation presents a set of user studies that evaluated the efficiency of psychophysiological interaction in desktop and virtual reality video games, and statistically assessed how the variations of player physiological data may relate to their respective changes in the perceived player experience. The dissertation also offers a set of ethical and methodological guidelines for the appropriate design of novel interaction techniques, and for the safe exposure of physiological sensors and virtual reality technologies to the general public.

The results obtained from this research show that the implementation of psychophysiological interaction in entertainment video games tends to positively affect player experience. However, this benefit comes as a tradeoff to player performance and their perceived sense of control. Additionally, the variations in electrodermal activity data, specifically in the skin conductance level, showed a tendency to correlate with negative player experience variables. Finally, psychophysiological interaction should be consistent with the natural behavior and reactions from players, and should be complementary to more traditional game interaction technologies.