Gaze behavior as a visual cue to animacy.

Abstract

A characteristic that distinguishes biological agents from inanimate objects is that the former can have a direction of attention. While it is natural to associate a person's direction of attention with the appearance of their face, attentional behaviors are also a kind of relational motion, in which an entity rotates a specific axis of its form in relation to an independent feature of its environment. Here, we investigated the role of gaze-like motion in providing a visual cue to animacy independent of the human form. We generated animations in which the rotation of a geometric object (the agent) was dependent on the movement of a target. Participants made judgements about how creature-like the objects appeared, which were highly sensitive to the correspondence between objects over and above their individual motion. We varied the dependence between agent rotation and target motion in terms of temporal synchrony, temporal order, cross-correlation, and trajectory complexity. These affected perceptions of animacy to differing extents. When the behavior of the agent was driven by a model of predictive tracking with a sensory sampling delay, perceived animacy was broadly tuned across changes in rotational behavior induced by the sampling delay of the agent. Overall, the tracking relationship provides a salient cue to animacy independent of biological form, provided that temporal synchrony between objects is within a certain range. This motion relationship may be one to which the visual system is highly attuned, due to its association with attentional behavior and the presence of other minds in our environment. (PsycInfo Database Record (c) 2022 APA, all rights reserved).