Perception of haptic motion is enhanced during conditions of increased postural stability

•Ambiguity of motion attribution (object/body) can be highlighted/manipulated.•Haptic perception of object motion is influenced by baseline postural state.•Haptic perception of object motion is enhanced with increasing object velocity. Coupling between postural sway and fingertip displacement has been observed in individuals lightly touching a moving surface. This can be attributed to the central nervous system (CNS) misinterpreting surface motion as self-motion, evoking a compensatory sway response. Does baseline postural state influence the correct perception of haptic object motion? Motion perception detection thresholds of index finger displacement at 1 mm s−1 velocity during light touch were determined for three postural conditions: standing with eyes open (EO) and closed (EC), and sitting with eyes closed. For the standing condition with eyes shut, displacement thresholds were measured using three velocities (1, 2 and 4 mm s−1). Postural condition had a large influence on motion perception, with a reduction in displacement threshold from 12 → 6 → 2 mm during the transition from standing EC → standing EO → sitting EC. A systematic decrease in displacement perception threshold was observed with increasing velocity. This tends to suggest that the increase of the touched object velocity may help overcoming the misinterpretation. These results suggest that the ability to disambiguate self motion from haptic motion is enhanced during stable postures, and when stimulus velocity is high. Our findings may help to understand the mechanisms underlying the coupling between surface movements and postural sway, reported in the literature.