Rothkegel et al. 20 Figure 5 . Summary statistics for saccade turning angles. (a) The distribution of angles between two successive saccades is markedly peaked at the 0 ◦ and 180 $^{◦}$. (b) Plot of the relation between saccade amplitude and turning angle contingent on parameters of the previous saccade. The previous saccadic endpoints are aligned to the origin. Saccade amplitudes were normalized to one and the saccade orientations were rotated to map the endpoints of a saccade with unit length to the point (1 , 0). This representation shows that most saccades either travel in the same direction as the previous saccade, but with reduced saccade amplitude, or shift gaze back to the starting position of the previous saccade, i.e., the point ( − 1; 0). (c) same as (b) but only for the first two saccades. This shows that after the long first fixation return saccades back to this position are hardly present. 0 500 1000 0 100 200 300 Angle [°] Frequency −1 0 1 −1 0 1 X−Component Y−Compononent 0.25 0.50 0.75 1.00 1.25 Intensity (a) (b) −1 0 1 −1 0 1 X−Component Y−Compononent 0.4 0.8 1.2 1.6 Intensity (c)