Word ambiguity and the optimal viewing position in reading

The optimal viewing position phenomenon discovered by (O'Regan, J. K., Lévy-Schoen, A., Pynte, J., Brugaillère, B. (1984). Convenient fixation location within isolated words of different length and structure. Journal of Experimental Psychology: Human Perception and performance. 10 (2), 250-257) is characterized by a minimization of gaze duration on a word and maximization of word recognition rates when the eye fixates a word near its center. Subsequent studies (Holmes, V. M., & O'Regan, J. K. (1987). Decomposing french words. In J. K. O'Regan, & A. Lévy-Schoen, Eye movements: from physiology to cognition, North-Holland, Amsterdam, 459-466; O'Regan, J. K., & Lévy-Schoen, A. (1987). Eye movement strategy and tactics in word recognition and reading. In M. Coltheart, Attention and performance XII: the psychology of reading, Erlbaum, Hillsdale N.J., 363-383) have shown that lexical structure can affect the location of the optimal viewing position. In this paper we show that the optimal viewing position is near to the position which minimizes word ambiguity arising from incomplete recognition of the letters in the word. This conclusion is supported by a statistical analysis based on inter-letter correlations in English and French word corpuses.