Fig. 3. Loading had no systematic effect on the initial direction of movement of the tarsus measured over the first 200 ms for scratches aimed at either the anterior (A) or posterior target (B). Median movement directions are represented by thick coloured vectors originating at the starting point of movement (black, unloaded; red, 142 mg load on the proximal femur; green, 142 mg load on the distal femur; blue, 142 mg load on the distal tibia). The correspondingly coloured long curved lines indicate the interquartile ranges of movement direction. The median velocity of movement over the first 200 ms is indicated by the length of each thick vector, and the interquartile range of velocity is indicated by the thin error bars (see Fig. 6 for additional analysis of movement velocity). Values of N are as follows. Anterior site, unloaded, 111; load on the proximal femur, 36; load on the distal femur, 33; load on the distal tibia, 40. Posterior site, N=121, 31, 34, 47 respectively.