Sensory Perception During Partial Pseudo-Haptics Applied to Adjacent Fingers

Pseudo-haptics, the phenomenon of creating a simulated tactile sensation by introducing a discrepancy between a voluntary movement and its visual feedback, is well known. Typically, when inducing pseudo-haptics, the same control-display ratio (C/D ratio) is applied to all effectors. However, with the aim of expanding the potential illusions that can be presented with pseudo-haptics, we investigated how perceived sensations change when partial pseudo-haptics are applied to adjacent body parts. In this research, we examined how perceived sensations change when pseudo-haptic stimuli are applied to adjacent body parts. Specifically, we investigated the correlation between finger states and the magnitude of illusory perception during both quasi-static and dynamic movements and identified the finger that experienced discomfort during dynamic movements with pseudo-haptics. Our findings revealed that: First, the magnitude of the illusion varied based on the contact state of adjacent fingers. Second, the illusion was more pronounced during dynamic movements compared to quasi-static movements. Third, regardless of the finger receiving the pseudo-haptic stimulus, the discomfort was primarily experienced in the finger exhibiting an overall inhibitory movement. The findings contribute to the practical application of pseudo-haptics as a virtual haptic display technology.