For the purposes of our experiment, we designed an experimental game called “Justin”. This game environment was inspired by the virtual pet game Tamagotchi, which also had an autonomous virtual character, but in a 2D environment (Higuchi & Troutt, 2004). Our game has a virtual simulation environment in 3D graphics, where the virtual character (animal or robot-animal beaver) explores a natural habitat. The virtual character moves randomly in the game environment. The player is instructed to take care of the character by supplying it with energy, break time, and fun during 10.16 minutes (609.6 seconds) through a “drag & drop” system. The players’ performance was indicated by increasing or decreasing level bars on the screen.

 

On the initial screen of the game, five virtual characters were displayed which allowed the researcher to choose with which character the participant would play. Then, to start playing the game, the participant had to press the “F9” key which saved an initial timestamp on the computer used later to synchronize different streams of data (record facial expressions of the player). The virtual characters in the experimental conditions (1) and (3) (the beaver or robot beaver) displayed facial expressions in the following order: 3 minutes of sadness, 3 minutes of neutral, 3 minutes of happiness, and 1 minute and 16 seconds of neutral. As the virtual characters in the other two experimental conditions (2) and (4) did not show emotional facial expressions, their appearance did not change during the game.

 

After 10 minutes, a“distress-inducing stimuli” was evoked in the game when another character (a hunter) came out from behind a bush and shot the beaver. After the distress situation, there was a delay of 16 seconds and then a screen appeared with the message: “Game Over”.

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Our control group (5) played with an amorphous figure as their virtual character. This virtual character had no emotional facial expressions, artificial or natural properties, or any particular kind of character. Its shape was indeterminate, and lacking a definite form (somewhat comparable to a marshmallow). The player took care of the character by supplying it with energy, break time, and fun during 10.16 minutes and they watched the same distress event as in the experimental situations and a message “Game Over”.