Abstract
Abstract: Purpose: To examine the use of spatial frequency information in the accurate programming of saccades. Methods: Subjects were asked to saccade to a Gabor patch which had a predefined spatial frequency content. In the first experiment, eight vertically oriented Gabor patches were presented in a centrally located circle of radius 4 degrees. One target (of a predefined spatial frequency content) was shown along with seven distractors (which all had a different spatial frequency content). In the second experiment, a target was presented on the horizontal meridian at either 3 or 6 degrees from the centre while a distractor was shown at the other eccentricity. Both patches were shown on the left or right hand side of the screen. The distance between the Gabor patches was identical in the two experiments. Subjects' eye movements were recorded on a DPI eyetracker. Results: Subjects could accurately direct first saccades on the basis of a difference in spatial frequency when the target was presented in the circular layout. However, subjects could no longer discount the presence of the distractor from the saccade programming when a distractor was placed between the target and the central fixation point. Conclusion: The results suggest that targets defined by spatial frequency can be accurately localized by peripherally pre-programmed saccades provided they are sufficiently far apart. The critical distance depends on the configuration of the Gabor patches rather than the absolute separation in visual space.