Figure 1.

Depiction of the pointing task and figure frame creation steps. (A) After two sets of calibrations, the participant is given instructions to point towards different points of a 3 × 3 matrix with their eyes closed (petrol arrow) in randomized order, i.e., as singular dots rather than as a consecutive nine-dot-shape. The pointing vectors are recorded by the device (as described in Ref.¹⁰) as spherical coordinates (visualized here by a hypothetical half dome centered on the participants shoulder). This test was repeated five times: (1) in the initial position, (2) following a 90° rotation to the non-hand-dominant side performed with open eyes, (3) following a 90° rotation back to the starting position performed with closed eyes, (4) following a 90° rotation to the hand-dominant side performed with open eyes, and (5) following a 90° rotation back to the starting position performed with closed eyes. (B) The pointing vector’s intersections with the half dome can then be projected onto a 2D plane, creating the individual figure frame for each paradigm. (C) This unitless visual representation of the 3D pointing performance (petrol dotted line) can then be compared to the original target structure (3 × 3 matrix, grey rectangle and dark grey dashed line).