Binocular coordination during reading
A basic assumption within eye movement research investigating reading is that each eye fixates the same point within a word. Consequently, movements of only one of the two eyes are usually recorded. In this series of studies we conducted an eye tracking experiment to investigate binocular coordination during reading. Sentences contained a critical compound word that we presented dichoptically (half the word presented to one eye, with the other half presented to the other). Results showed that each eye fixated 1-2 characters apart on 47% of fixations and that the majority of disparate fixations were uncrossed. Also, systematic vergence movements occurred during fixation. While the dichoptic manipulation influenced fixation durations, it did not affect fixation positions on a word. Our results indicate that the assumption that both eyes fixate the same location is not correct for all fixations and that the oculomotor control system operates according to a fused visual signal.