Pseudo-Haptic Heaviness Influenced by the Range of the C/D Ratio and the Position of the C/D Ratio Within a Given Range

Pseudo-haptic heaviness refers to the illusory sensation of heaviness caused by a dissociation in amplitudes between object movements on a screen and users' motor actions. The amplitude ratio of object movements to the user's actions, the so-called C/D ratio, is a powerful determinant of pseudo-haptic heaviness. According to previous studies, perceptual judgments for a given stimulus value are influenced by the position of the value within a given stimulus range, while no studies have shown the same to be true for pseudo-haptic heaviness. The present study examined whether pseudo-haptic heaviness determined by the C/D ratio was influenced by the range of C/D ratios, and also, by the position of the C/D ratio within a given range. Participants were asked to drag and lift a square on the screen up to a target line and then rate its heaviness; the range of C/D ratios was controlled as a between-participants factor. We observed a phenomenon whereby both the range and position of the C/D ratio influenced the rated heaviness. This phenomenon was clearly established over 8 experimental trials. We conclude that both the C/D ratio range and the position of the C/D ratio within a given range are determinants for pseudo-haptic heaviness.