| Popis: |
Variability is a property of biological systems, and in animals (including humans) behavioral variability is characterized by certain features, such as the range of variability and shape of its distribution. Nevertheless, only a few studies have investigated whether and how variability features contribute to the ascription of humanness to robots in a human-robot interaction setting. Here, we tested whether two aspects of behavioral variability, namely the standard deviation and shape of distribution of reaction times, affect the ascription of humanness to robots during a joint action scenario. We designed an interactive task in which pairs of participants performed a joint Simon task. The members of each pair were seated in two separate experimental cabins. Each member of the pair performed the joint task with the robot, iCub, placed by their side. The joint task required reacting with a button press to a visual stimulus presented on the screen. The critical manipulation was that the iCub robot could either perform the task in a pre-programmed manner or its button presses could be teleoperated by the other member of the pair, seated in the other room. In the pre-programmed condition, the iCub pressed the buttons with reaction times falling within the range of human variability. However, the distribution of the reaction times did not resemble human-like shape. Results showed that participants were sensitive to humanness, since they correctly detected the human agent above chance level. When the iCub was controlled by the computer program, it passed our variation of a non-verbal Turing test. Taken together, our results suggest that hints of humanness, such as the range of behavioral variability, might be used by observers to ascribe humanness to a humanoid robot. In consequence, the robot endowed with such behavioral characteristics would pass a non-verbal variation of a Turing test. |
