Table 1.Eye movement characteristics in reading,scene perception,and visual search. Typical mean Mean Saccade Size Task fixation duration (ms) (degrees) Silent Reading 225~250 2(8-9 letter spaces) Oral Reading 275-325 1.5 (6-7 letter spaces) Scene Perception 260~330 4 Visual Search 180~275 3 http://www.scholarpedia.org/article/Eye_movementsTask Typical mean fixation duration (ms) Mean Saccade Size (degrees) Silent Reading 225~250 2 (8-9 letter spaces) Oral Reading 275~325 1.5 (6-7 letter spaces) Scene Perception 260~330 4 Visual Search 180~275 3 Table 1. Eye movement characteristics in reading, scene perception, and visual search. http://www.scholarpedia.org/article/Eye_movements