Figure 6.

Relationship between the predicted perceived roughness and observed perceived roughness based on the generalized linear models with the contributions from velocity-linked vibratory power (V_p), spatial image (S), motor (M), proprioception (P), and their interactive terms (S · M and S · P). Proprioceptive inputs contribute more to roughness constancy than the motor efference copy does by reducing the velocity effect (i.e., increasing vibratory power by increasing velocities). Where the contribution of a particular component (V_p, S, M, P, or any interactive term) is not significant, no plot is shown. Perceived roughness is shown on the ordinate, and the log of scanning velocity (20, 40, 80, 160, 220 mm/s) is represented on the abscissa for the top seven rows. The data for six scanning conditions are shown: active finger, active probe, passive finger, passive probe, pseudo-passive finger, and pseudo-passive probe. The observed roughness ratings (R_o) are the average over seven texture stimuli for five velocities in each scanning condition. The predicted roughness ratings (R_p) are the sum of the contributions from V_p, S, M, P, and interactive terms S · M and S · P. Bottom, Correlations between observed (R_o) and predicted (R_p) roughness ratings for seven textures and five velocities in each scanning condition.