DESCRIPTION: This application for a Research Scientist Award has four broad objectives. The first is to continue to investigate perceptual processes in reading. This research will focus on the types of codes that are used in integrating information across eye movements and the accrual of information during an eye fixation. A second objective is to use modeling techniques to simulate eye movements and reading behavior. The goal here is to develop formal models that can predict where readers will fixate and for how long they will fixate during reading. The third objective is to extend the applicant's prior research on reading to the perception of visual scenes. Experiments are designed to examine the characteristics of the perceptual span during scene perception and the types of information integrated across fixations using photographic images rather than the line drawings used in previous research. The fourth goal is to use eye movement techniques to investigate on-line language processing. The studies in this section focus on how readers deal with ambiguity and the extent to which discourse factors influence on-line decisions about ambiguous parts of a text. The experiments will use techniques that have been developed in the applicant's laboratory over the past 20 years. In these techniques, changes in text are made contingent on the location of the reader's eye. The changes may take place during a saccade or during an eye fixation. Various characteristics of eye movements are measured using an eyetracker. The empirical data collected and the results of the modeling work should help to develop a better model of the processes involved in skilled reading. A better understanding of skilled reading, in turn, should be useful in developing instructional methods for children learning to read and better remedial methods for those who do not read well.