Effects of voice prosody by computers on human behaviors

This paper examines whether a human is aware of slight prosodic differences in a computer voice and changes his/her behaviors accordingly through interaction, when the prosodic difference carries informational significance. We conduct a route selection experiment, in which subjects were asked to find a route in a computer generated 3-D maze. The maze system occasionally provides a confirmation in response to the subject's choice of a route. The prosodic characteristics of confirmation utterances are made to marginally change according to whether the route selected is the right route for reaching the goal or a wrong route that ends up in a cul de sac. In this experiment, subjects are able to pick up the difference and successfully navigate through the maze. This result demonstrates that subjects are sensitive to even a slight change in the voice's prosodic characteristics and that computer voice prosody can affect the route selection behaviors of subjects.