Article

Attention doesn't slide: spatiotopic updating after eye movements instantiates a new, discrete attentional locus.

Interdepartmental Neuroscience Program, Yale University, New Haven, CT, USA.
Attention Perception & Psychophysics (Impact Factor: 2.15). 01/2011; 73(1):7-14. DOI: 10.3758/s13414-010-0016-3
Source: PubMed

ABSTRACT During natural vision, eye movements can drastically alter the retinotopic (eye-centered) coordinates of locations and objects, yet the spatiotopic (world-centered) percept remains stable. Maintaining visuospatial attention in spatiotopic coordinates requires updating of attentional representations following each eye movement. However, this updating is not instantaneous; attentional facilitation temporarily lingers at the previous retinotopic location after a saccade, a phenomenon known as the retinotopic attentional trace. At various times after a saccade, we probed attention at an intermediate location between the retinotopic and spatiotopic locations to determine whether a single locus of attentional facilitation slides progressively from the previous retinotopic location to the appropriate spatiotopic location, or whether retinotopic facilitation decays while a new, independent spatiotopic locus concurrently becomes active. Facilitation at the intermediate location was not significant at any time, suggesting that top-down attention can result in enhancement of discrete retinotopic and spatiotopic locations without passing through intermediate locations.

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