Uncanny Valley Curve or Linear Relationship? The Different Influences of Robots’ Human-Likeness on Mind Perception and Visuospatial Perspective-Taking

High but imperfect human likeness (HL) of robot appearance may elicit negative emotional responses of people, which is called the Uncanny Valley (UV) effect. Meanwhile, robots' human-like appearances also influence people's mind perception and behaviors toward robots, but it is not clear whether the influences also follow the UV curve. Moreover, the relationship between mind perception and behavior remains an open question. This study recruited 256 participants and employed 72 real-world robots with different levels of human-like appearance. Participants' spontaneous visuospatial perspective-taking, along with their subjective ratings of robots' likability and mind perception were measured. The results revealed that with the HL score of robots increasing, likability and mind perception showed UV curves, but perspective-taking exhibited an increasingly linear line. At the same time, the relationship between perspective-taking and mind perception was weak. These empirical findings provided insights into theories related to people's mind perceptions and behaviors toward robots.