Video-oculographic data of the 99 subjects.

aMann-Whitney-U-test between healthy controls and all ALS patientsbKruskal-Wallis analysis of variances on ranks (ANOVA) between healthy controls, ALS patients with bulbar and spinal onset. Post-hoc comparison in the event of ANOVA pU-test: p† and p†; p = 0.035 for ALS patients with bulbar onset compared with ALS patients with spinal onset#cGain of VGRS aimed at targets of 20° eccentricity obtained by linear fitting saccade amplitudes as a function of target stepsdLatencies of VGRS with respect to primary saccade onsetePeak eye velocity of VGRS aimed at targets of 20° eccentricity obtained by non-linear interpolation along the main sequencefSaccadic intrusions (>2°) excluding the primary saccade, computed as the sum of saccades within VGRS acquisition timegErroneous responses (saccades before cue)hErroneous responses (pro-saccades)iSaccades (>10°) counted within 30sData are depicted as median (interquartile range), min-max; post-hoc comparisons (for pair-wise statistical interference between ALS patients spinal onset, ALS patients bulbar onset and controls) reaching statistical significance are indicated as upper scripts † and # (see subsequent footnotes for details).