Evaluation of Flow Experience by using Psychophysiological Visual Feedbacks

Objective: The present study aims to evaluate the visual reactions of users when they are playing games of different flow levels, and to explore the visual variables that can sensitively reflect the different flow levels. Background: The flow is defined as a psychological state where interface users feel their actions in a virtual setting identical to those in real environment. To measure the flow states of users, the questionnaire-based FSS(Flow State Scale) has mostly been used. However, this method is a qualitative test that has limits in terms of the accuracy of users' flow experiences. Therefore, more accurate methods to measure users' flow experiences are required. Method: Ten subjects participated in the experiment, where the independent variables were three games with different flow levels(puzzle games, dot drawing and coloring) and the time frame(the first and last 10 seconds in game playing), whereas the dependent variables included the pupil size and the frequency and duration of eye blinking. This study was a within-subject design. Each participant performed three types of games with different flow levels 3 times for each for 10 minutes, and their visual reactions to each game were measured. Results: The higher the flow cause the bigger pupil size(p<0.01) and the lower eye blinking frequency(p<0.1), indicating that different types of games lead to different flow levels. The pupil size during the last 10 seconds when the flow level was higher was bigger by 2.1% compared with that during the first 10 seconds in game playing(p<0.1), and the eye blinking frequency decreased by 12%(p<0.01). Conclusion: It was found out that the pupil size and the frequency and duration of eye blinking were psychophysiological indices for evaluating users' flow experiences, which could quantify the flow states users go through. The psychophysiological variables capable of measuring diverse aspects of the flow need diversifying to be applicable to precise measurement of the flow. Application: These studies are warranted for both quantitative analysis of flow levels and qualitative improvement of cyber leisure in line with development of healthy games.