The haptic radial-tangential effect: Two tests of Wong’s “moments-of-inertia” hypothesis

Abstract When a given length is haptically traced, the direction of hand movements (relative to the body) influences the length perceived. A recent theory by Wong (1977) states that the source of the illusion is undetected differences in the moments of inertia associated with different directions of...
Ausführliche Beschreibung

Abstract When a given length is haptically traced, the direction of hand movements (relative to the body) influences the length perceived. A recent theory by Wong (1977) states that the source of the illusion is undetected differences in the moments of inertia associated with different directions of hand movement: Radial directions produce greater resistance to inertia (and, therefore, slower movements) than do tangential directions. Because subjects rely on time estimates to determine a fixed distance and because they are unable to perceive that they are moving more slowly in the radial than in the tangential direction, they overestimate “radial” lengths relative to“tangential” lengths. Experiment 1 examines the effect of altering inertia by changing the distance of the hand from the axis of rotation; Experiment 2 does so by changing the mass of the moving hand. Both manipulations fail to support the predictions derived from the moments-of-inertia hypothesis. Ausführliche Beschreibung