Speed Discrimination in the Apparent Haptic Motion Illusion.

When talking about the Apparent Haptic Motion (AHM) illusion, temporal parameters are the most discussed for providing the smoothest illusion. Nonetheless, it is rare to see studies addressing the impact of changing these parameters for conveying information about the velocity of the elicited motion sensation. In our study, we investigate the discrimination of velocity changes in AHM and the robustness of this perception, considering two stimulating sensations and two directions of motion. Results show that participants were better at discriminating the velocity of the illusory motion when comparing stimulations with higher differences in the actuators activation delay. Results also show limitations for the integration of this approach in everyday life applications.