The span of the effective stimulus during a fixation in reading


A computer-based eye-movement controlled, display system was developed for the study of perceptual processes in reading. A study was conducted to identify the region from which skilled readers pick up various types of visual information during a fixation while reading. This study involved making display changes, based on eye position, in the text pattern as the subject was in the act of reading from it, and then examining the effects these changes produced on eye behavior. The results indicated that the subjects acquired word-length pattern information at least 12 to 15 character positions to the right of the fixation point, and that this information primarily influenced saccade lengths. Specific letter- and word-shape information were acquired no further than 10 character positions to the right of the fixation point.

Reference Note

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Corresponding author

Correspondence to George W. McConkie.

Additional information

The research described in this report was earned out at the Artificial Intelligence Laboratory at the Massachusetts Institute of Technology.

The research was made possible by a Special Fellowship from the National Institute of Mental Health to the senior author and by Grant OEG-2-71-0531 from the Office of Education. Portions of these data were reported at the 1973 meetings of the Eastern Psychological Association and the American Educational Research Association.

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McConkie, G.W., Rayner, K. The span of the effective stimulus during a fixation in reading. Perception & Psychophysics 17, 578–586 (1975).

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  • Fixation Duration
  • Central Vision
  • Display Change
  • Normal Text