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Exocentric pointing in the visual field.

van Doorn A, Koenderink J, Wagemans J - Iperception (2013)

Bottom Line: Phenomenologically, such pointings show systematic deviations from veridicality of several degrees.The errors are very small in the vertical and horizontal directions, but appreciable in oblique directions.A general conclusion is that the visual field cannot be described in terms of one of the classical homogeneous spaces, or, alternatively, that the results from pointing involve mechanisms that come after geometry proper has been established.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Experimental Psychology, University of Leuven (KU Leuven), Tiensestraat 102 box 3711, B-3000 Leuven, Belgium; and Faculteit Sociale Wetenschappen, Psychologische Functieleer, Universiteit Utrecht, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands; e-mail: andrea.vandoorn@telfort.nl.

ABSTRACT
"Exocentric pointing in the visual field" involves the setting of a pointer so as to visually point to a target, where both pointer and target are objects in the visual field. Phenomenologically, such pointings show systematic deviations from veridicality of several degrees. The errors are very small in the vertical and horizontal directions, but appreciable in oblique directions. The magnitude of the error is largely independent of the distance between pointer and target for stretches in the range 2-27°. A general conclusion is that the visual field cannot be described in terms of one of the classical homogeneous spaces, or, alternatively, that the results from pointing involve mechanisms that come after geometry proper has been established.

No MeSH data available.


Related in: MedlinePlus

The zero crossings calculated from the smoothed data shown in Figure 4. These plots allow a more intuitive overview of the data. For ease of reference the zero crossings corresponding to the horizontal and vertical directions have been printed black, those corresponding to the oblique directions gray.
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Figure 5: The zero crossings calculated from the smoothed data shown in Figure 4. These plots allow a more intuitive overview of the data. For ease of reference the zero crossings corresponding to the horizontal and vertical directions have been printed black, those corresponding to the oblique directions gray.

Mentions: The smoothed data of Figure 4 allow a fairly precise estimate of the zero crossings that are the directions into which the median of the pointings happens to be veridical (Figure 5). Apparently the observers largely agree, and are close to veridical for the horizontal or vertical directions, but somewhat deviate from each other, and have appreciable spread in the diagonal directions.


Exocentric pointing in the visual field.

van Doorn A, Koenderink J, Wagemans J - Iperception (2013)

The zero crossings calculated from the smoothed data shown in Figure 4. These plots allow a more intuitive overview of the data. For ease of reference the zero crossings corresponding to the horizontal and vertical directions have been printed black, those corresponding to the oblique directions gray.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4129387&req=5

Figure 5: The zero crossings calculated from the smoothed data shown in Figure 4. These plots allow a more intuitive overview of the data. For ease of reference the zero crossings corresponding to the horizontal and vertical directions have been printed black, those corresponding to the oblique directions gray.
Mentions: The smoothed data of Figure 4 allow a fairly precise estimate of the zero crossings that are the directions into which the median of the pointings happens to be veridical (Figure 5). Apparently the observers largely agree, and are close to veridical for the horizontal or vertical directions, but somewhat deviate from each other, and have appreciable spread in the diagonal directions.

Bottom Line: Phenomenologically, such pointings show systematic deviations from veridicality of several degrees.The errors are very small in the vertical and horizontal directions, but appreciable in oblique directions.A general conclusion is that the visual field cannot be described in terms of one of the classical homogeneous spaces, or, alternatively, that the results from pointing involve mechanisms that come after geometry proper has been established.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Experimental Psychology, University of Leuven (KU Leuven), Tiensestraat 102 box 3711, B-3000 Leuven, Belgium; and Faculteit Sociale Wetenschappen, Psychologische Functieleer, Universiteit Utrecht, Heidelberglaan 2, 3584 CS Utrecht, The Netherlands; e-mail: andrea.vandoorn@telfort.nl.

ABSTRACT
"Exocentric pointing in the visual field" involves the setting of a pointer so as to visually point to a target, where both pointer and target are objects in the visual field. Phenomenologically, such pointings show systematic deviations from veridicality of several degrees. The errors are very small in the vertical and horizontal directions, but appreciable in oblique directions. The magnitude of the error is largely independent of the distance between pointer and target for stretches in the range 2-27°. A general conclusion is that the visual field cannot be described in terms of one of the classical homogeneous spaces, or, alternatively, that the results from pointing involve mechanisms that come after geometry proper has been established.

No MeSH data available.


Related in: MedlinePlus