| Affiliation: | (1) Department of Psychology, CIHR Group on Action and Perception, University of Western Ontario, London, ON, Canada, N5A 6C2;(2) Department of Psychology and Centre for Neuroscience Studies, Queen’s University, Kingston, ON, Canada, K7L 3N6;(3) Institute of Cognitive Neuroscience, National Central University, No. 300, Jhongda Rd, Jhongli City, Taoyuan County, 32001, Taiwan |
| Abstract: | It is known that dense objects seem heavier than larger, less dense objects of the same weight. We have investigated a related illusion, in which visual context biases the apparent weight of a single object. The apparatus is a cabin on a steep hillside near Santa Cruz, CA, tilted 17° from vertical. From its ceiling hangs a weight on a chain. The cabin’s tilt makes the weight appear suspended at an angle. Pushing the weight toward the visually based vertical is perceived as difficult, whereas pushing it away from the visual vertical is perceived as easy. Seven subjects pushed the weight in both directions, judging required effort on a double-anchored 1–10 scale. All experienced the effort illusion, with no significant subject effect. When subjects’ eyes were closed, the effect was smaller but still present. Apparently proprioceptive and skin inputs, equal for both directions, are ignored or underweighted as visually based expectations influence perceived effort. |
