Figure 2.

Example of a display shown in the task and a small portion of gaze data (red line). Subjects, after a fixation point of 500 ms, were asked to follow an alphanumeric sequence (1-A-2-B-3-C-4-D-5-E) with their gaze. The numbers and letters appeared in a pseudorandom distribution (letters on top and numbers on the bottom) on a 1024 × 768 px and 51 × 31 cm black screen for 30000 ms. The red line shows some fixations and saccades made by a healthy subject. Saccades are rapid eye jumps from one region to another region. During fixations (time duration ≈100 ms ⋯ 800 ms) humans acquire information from objects.