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Orientation tuning of a two-stimulus afterimage: Implications for theories of filling-in.

Van Horn DR, Francis G - Adv Cogn Psychol (2008)

Bottom Line: From the analysis, we show that the model must predict a rapid drop in afterimage occurrence as the gratings deviate from orthogonal.We then report on 2 experiments that test the properties of the model and find that the experimental data are strikingly different from the model predictions.From these discrepancies we identify the key deficits of the current version of the model.

View Article: PubMed Central - PubMed

Affiliation: Psychological Sciences, Purdue University,West Lafayette, IN, USA.

ABSTRACT
Sequential viewing of 2 orthogonally related gratings produces an afterimage related to the firstgrating (Vidyasagar, Buzas, Kisyarday, & Eysel, 1999; Francis & Rothmayer, 2003). We investigated how the appearance of the afterimage depended on the relative orientations of the 2 stimulus gratings. We firstanalyzethetheoretical explanation of the appearance of the afterimage that was proposed by Francis and Rothameyer (2003). From the analysis, we show that the model must predict a rapid drop in afterimage occurrence as the gratings deviate from orthogonal. We also show that the model predicts that the shape of the afterimage should always be orthogonal to the second grating. We then report on 2 experiments that test the properties of the model and find that the experimental data are strikingly different from the model predictions. From these discrepancies we identify the key deficits of the current version of the model.

No MeSH data available.


The sequence of images for an experimental trial in Experiment 2. The							orientation of the second stimulus varied from trial to trial. Any							afterimages were measured during the second blank frame.
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Figure 11: The sequence of images for an experimental trial in Experiment 2. The orientation of the second stimulus varied from trial to trial. Any afterimages were measured during the second blank frame.

Mentions: Figure 11 provides a schematic for one of the trials a observer might observe during the experiment. Observers started each trial with a key press, which was followed by the presentation of stimuli, which were shown on a gray background and viewed at a distance of 45 cm. S1 consisted of two intersecting bar gratings. The gratings were presented within a circular aperture that had a diameter of 10 cm (12.6° of visual angle) and were shown for 1 s. Each grating consisted of five vertical black bars that intersected with five horizontal black bars on a white background. A small red box was placed in the middle of the display as a fixation point. Gray, white, and black had a luminance of 40, 97, and 0.5 cd/m2, respectively.


Orientation tuning of a two-stimulus afterimage: Implications for theories of filling-in.

Van Horn DR, Francis G - Adv Cogn Psychol (2008)

The sequence of images for an experimental trial in Experiment 2. The							orientation of the second stimulus varied from trial to trial. Any							afterimages were measured during the second blank frame.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2864993&req=5

Figure 11: The sequence of images for an experimental trial in Experiment 2. The orientation of the second stimulus varied from trial to trial. Any afterimages were measured during the second blank frame.
Mentions: Figure 11 provides a schematic for one of the trials a observer might observe during the experiment. Observers started each trial with a key press, which was followed by the presentation of stimuli, which were shown on a gray background and viewed at a distance of 45 cm. S1 consisted of two intersecting bar gratings. The gratings were presented within a circular aperture that had a diameter of 10 cm (12.6° of visual angle) and were shown for 1 s. Each grating consisted of five vertical black bars that intersected with five horizontal black bars on a white background. A small red box was placed in the middle of the display as a fixation point. Gray, white, and black had a luminance of 40, 97, and 0.5 cd/m2, respectively.

Bottom Line: From the analysis, we show that the model must predict a rapid drop in afterimage occurrence as the gratings deviate from orthogonal.We then report on 2 experiments that test the properties of the model and find that the experimental data are strikingly different from the model predictions.From these discrepancies we identify the key deficits of the current version of the model.

View Article: PubMed Central - PubMed

Affiliation: Psychological Sciences, Purdue University,West Lafayette, IN, USA.

ABSTRACT
Sequential viewing of 2 orthogonally related gratings produces an afterimage related to the firstgrating (Vidyasagar, Buzas, Kisyarday, & Eysel, 1999; Francis & Rothmayer, 2003). We investigated how the appearance of the afterimage depended on the relative orientations of the 2 stimulus gratings. We firstanalyzethetheoretical explanation of the appearance of the afterimage that was proposed by Francis and Rothameyer (2003). From the analysis, we show that the model must predict a rapid drop in afterimage occurrence as the gratings deviate from orthogonal. We also show that the model predicts that the shape of the afterimage should always be orthogonal to the second grating. We then report on 2 experiments that test the properties of the model and find that the experimental data are strikingly different from the model predictions. From these discrepancies we identify the key deficits of the current version of the model.

No MeSH data available.