Fig. 1.

a Images of the items used in the experiment. From left to right: hand, rake, post-it, box presented to the participant in upright (top row) and rotated (bottom row) orientation. The yellow and red lines on the items were not present during experimentation and have been drawn to illustrate the item-centric width and length dimensions used to calculate the Shape Index (SI). The terms “length” and “width” always refer to the item-centric length and width; for example, in the upright orientation the “length” of the hand, rake, post-it and box is vertical (top row, red line), and in the rotated orientation, the “length” is horizontal from the viewer’s perspective (bottom row, red line). The lines on the green background were of a known size and used to calculate the actual hand size from the images. b Image of the experimental setup in the localization task, in the condition where the participant estimated the landmarks on the left hand (color figure online)