Figure 1

Experimental design and stimuli. (A) Design of the contact phase. Participants pressed the right or left button when the fixation point became brighter. The avatars turned left or right; the timing and direction of turning differed by condition. (B) Design of the recognition phase. Participants observed the static avatars and rated them by pressing the button. Participants answered three questions: “Do you like the avatar?”, “Do you think the avatar is nice?”, and “Do you want the avatar?”. (C) The four avatar conditions. We presented the four avatar types, each representing a different condition, and used a 2 × 2 design (2 contingency factors × 2 face perception factors): face contingent (FC), face non-contingent (FN), object contingent (OC), and object non-contingent (ON). We drew the four avatars in different colors (red, blue, yellow, and green) to ensure that participants could identify the avatar type. (D) Sequence of the functional magnetic resonance imaging (fMRI) experiment. In total, 12 trials of the contact and recognition phases comprised one block, and four such blocks comprised one session. Participants completed five sessions in an MRI scanner. Before each session, participants rated the avatars (“Pre rating” in D); these ratings represent the baseline scores.