Publications by authors named "L A Carlson-Radvansky"

Spatial relational terms like above are defined with respect to a reference frame. Reference frames are imposed on reference objects and define the space in which to search for a located object. Reference frames have a number of parameters that must be set during spatial term assignment, including origin, scale, and orientation.

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Although the proximal stimulus shifts position on our retinae with each saccade, we perceive our world as stable and continuous. Most theories of visual stability implicitly assume a mechanism that spatially adjusts perceived locations associated with the retinal array by using, as a parameter, extra-retinal eye position information, a signal that encodes the size and direction of the saccade. The results from the experiment reported in this article challenge this idea.

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Structural descriptions are hierarchical representations of a visual stimulus in terms of its parts and their relations. Previous research in which the retention of parts was examined has shown that structural descriptions can be used to represent information in transsaccadic memory. In three experiments, this idea was tested further by examining whether relational information is also maintained across saccades.

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Magnitude estimations involving spatial characteristics, such as distance, typically show a compressive function when estimates are made from memory. In particular, as the magnitude of a property grows larger and larger, estimates become more and more inaccurate, with increasing underestimates of the actual magnitude. Previous theories have attempted to explain this difference by supposing that magnitude estimation was accomplished through a reperceptual process, in which the errors of perception are magnified, or a transformation process, in which the memory trace undergoes a consistent alteration toward a more schematic form.

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Spatial terms such as "above" must be used and interpreted with respect to some frame of reference. Perceptual cues for verticality were varied in four experiments to investigate whether the comprehension and production of "above" is based on a viewer-centered (deictic) frame, an environment-centered (extrinsic) frame, or an object-centered (intrinsic) frame of reference. "Above" was usually interpreted with respect to an environment-centered reference frame, but there was a significant contribution from object-centered reference frames as well; the viewer-centered reference frame made no independent contribution to "above".

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