Goal-related feedback guides motor exploration and redundancy resolution in human motor skill acquisition
Fig 4
Examples of synergies learned.
Two example solutions from different participants in the test phase for Condition H1 (A+B) and Condition H2 (C+D) respectively (first two synergies PC1 and PC2). Panels A and C depict the PC1/PC2 solution plane in the three-dimensional motor space. The plane extends 2σ (standard deviations) away from the central posture in the directions of PC1 and PC2 respectively. The pale ‘shadows’ are projections of the results onto the planes defined by the coordinate axes for a better impression of 3D shape. The empty disks depict the two home postures H1 and H2. Panels B and D depict the same result in the goal space (colour code is identical to A and C). The thick lines depict the arm configurations that correspond to the points of the same colour in motor space. The thin lines depict the reach-endpoints along the grid that connects the dots. The inlays depict the respective home postures H1 and H2.