The effects of body direction and posture on taking the perspective of a humanoid avatar in a virtual environment

Abstract

Visual perspective taking is inferring how the world looks to another person. To clarify this process, we investigated whether employing a humanoid avatar as the viewpoint would facilitate an imagined perspective shift in a virtual environment, and which factor of the avatar is effective for the facilitation effect. We used a task that involved reporting how an object looks by a simple direction judgment, either from the avatar’s position or from the position of an empty chair. We found that the humanoid avatar’s presence improved task performance. Furthermore, the avatar’s facilitation effect was observed only when the avatar was facing the visual stimulus to be judged; performance was worse when it faced backwards than when there was only an empty chair facing forwards. This suggests that the avatar does not simply attract spatial attention, but the posture of the avatar is crucial for the facilitation effect. In addition, when the directions of the head and the torso were opposite (i.e., an impossible posture), the avatar’s facilitation effect disappeared. Thus, visual perspective taking might not be facilitated by the avatar when its posture is biomechanically impossible because we cannot embody it. Finally, even when the avatar’s head of the possible posture was covered with a bucket, the facilitation effect was found with the forward-facing avatar rather than the backward-facing avatar. That is, the head/gaze direction cue, or presumably the belief that the visual stimulus to be judged can be seen by the avatar, was not required. These results suggest that explicit perspective taking is facilitated by embodiment towards humanoid avatars.

No signs of automatic perspective-taking or its modulation by joint attention in toddlers using an object retrieval task

“…[ 17 , 18 ] replicated the findings with both adults and school children, suggesting that humans, across developmental stages, represent others' perspectives even when it impairs performance (see also [ 19 ]). The opposite effect— enhanced performance due to automatic perspective-taking—has also been reported, with adults detecting low-contrast patterns faster in the co-presence of an avatar ([ 20 ], see also [ 21 ]). In another study, participants inhibited distractors not only of their own but also of others’ manual tasks, indicating that they automatically shifted to allocentric frames of reference [ 22 ].…”