Foveal vision anticipates defining features of eye movement targets
High-acuity foveal processing is vital for human vision. Nonetheless, little is known about how the preparation of large-scale rapid eye movements (saccades) affects visual sensitivity in the center of gaze. Based on findings from passive fixation tasks, we hypothesized that during saccade preparation, foveal processing anticipates soon-to-be fixated visual features. Using a dynamic large-field noise paradigm, we indeed demonstrate that defining features of an eye movement target are enhanced in the pre-saccadic center of gaze. Enhancement manifested as higher Hit Rates for foveal probes with target-congruent orientation and a sensitization to incidental, target-like orientation information in foveally presented noise. Enhancement was spatially confined to the center of gaze and its immediate vicinity, even after parafoveal task performance had been raised to a foveal level. Moreover, foveal enhancement during saccade preparation was more pronounced and developed faster than enhancement during passive fixation. Based on these findings, we suggest a crucial contribution of foveal processing to trans-saccadic visual continuity: Foveal processing of saccade targets commences before the movement is executed and thereby enables a seamless transition once the center of gaze reaches the target.
All data (psychophysical data, timing data, eye movement data, stimulus information) along with all experimental scripts are available on the Open Science Framework: https://osf.io/v9gsq/
Article and author information
Deutsche Forschungsgemeinschaft (RO3579/8-1)
- Martin Rolfs
Deutsche Forschungsgemeinschaft (RO3579/9-1)
- Martin Rolfs
Deutsche Forschungsgemeinschaft (RO3579/12-1)
- Martin Rolfs
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: Participants gave written informed consent before the experiments. All studies complied with the Declaration of Helsinki in its latest version and were approved by the Ethics Committee of the Department of Psychology at Humboldt-Universität zu Berlin (reference number: 2018-09).
- Krystel R Huxlin, University of Rochester, United States
- Preprint posted: January 12, 2022 (view preprint)
- Received: February 23, 2022
- Accepted: September 3, 2022
- Accepted Manuscript published: September 9, 2022 (version 1)
- Accepted Manuscript updated: September 13, 2022 (version 2)
- Version of Record published: October 18, 2022 (version 3)
© 2022, Kroell & Rolfs
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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