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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.


A schematic of the stimuli and percepts of the two-stimulus afterimage.
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Figure 1: A schematic of the stimuli and percepts of the two-stimulus afterimage.

Mentions: Francis and Rothmayer (2003) reported that sequential viewing of two orthogonally related patterns produces an afterimage percept related to the first pattern. They explained this afterimage using Grossberg’s (1994) FACADE theory. Figure 1a shows a sequence of images that produces the afterimage (Francis & Rothmayer, 2003). The first stimulus (S1) consisted of black and white vertical bars on a gray background that was presented for 1 s. S1 was replaced by a blank gray screen (B1) for a duration of 1 s. B1 was then replaced by a second stimulus (S2), which was made of horizontal black and white bars that flickered with their achromatic color complements. Finally, the observer was shown another blank screen (B2) and at the end of this blank the observer was asked to report on any afterimages.


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

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

A schematic of the stimuli and percepts of the two-stimulus afterimage.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 1: A schematic of the stimuli and percepts of the two-stimulus afterimage.
Mentions: Francis and Rothmayer (2003) reported that sequential viewing of two orthogonally related patterns produces an afterimage percept related to the first pattern. They explained this afterimage using Grossberg’s (1994) FACADE theory. Figure 1a shows a sequence of images that produces the afterimage (Francis & Rothmayer, 2003). The first stimulus (S1) consisted of black and white vertical bars on a gray background that was presented for 1 s. S1 was replaced by a blank gray screen (B1) for a duration of 1 s. B1 was then replaced by a second stimulus (S2), which was made of horizontal black and white bars that flickered with their achromatic color complements. Finally, the observer was shown another blank screen (B2) and at the end of this blank the observer was asked to report on any afterimages.

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.