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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 main components of FACADE theory. The input image feeds						into a retinotopic representation of black and white, which compete in a						gated dipole circuit. The gated dipole circuit produces complementary						after-responses. The black and white information then feeds into edge						detection in the BCS, which also contains a gated dipole circuit whose						after-responses code orthogonal orientations. The edges in the BCS guide the						spread of black and white information in the FCS filling-in stage to limit						the spread of color and brightness information.
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Figure 2: A schematic of the main components of FACADE theory. The input image feeds into a retinotopic representation of black and white, which compete in a gated dipole circuit. The gated dipole circuit produces complementary after-responses. The black and white information then feeds into edge detection in the BCS, which also contains a gated dipole circuit whose after-responses code orthogonal orientations. The edges in the BCS guide the spread of black and white information in the FCS filling-in stage to limit the spread of color and brightness information.

Mentions: Francis and Rothmayer (2003) and Francis and Schoonveld (2005) reported simulations of Grossberg’s (1994) FACADE model that accounted for the appearance of the afterimage. In this theory, two separate pathways are used to compute visual information. Figure 2 shows a schematic of the major parts of the model. A boundary contour system (BCS) processes boundary or edge information, while a feature contour system (FCS) uses information from the BCS to allow diffusive filling-in of surface properties like color and brightness. The BCS detects oriented edges. The FCS uses the BCS information to determine where information spreads, leading to the final percept.


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 main components of FACADE theory. The input image feeds						into a retinotopic representation of black and white, which compete in a						gated dipole circuit. The gated dipole circuit produces complementary						after-responses. The black and white information then feeds into edge						detection in the BCS, which also contains a gated dipole circuit whose						after-responses code orthogonal orientations. The edges in the BCS guide the						spread of black and white information in the FCS filling-in stage to limit						the spread of color and brightness information.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Figure 2: A schematic of the main components of FACADE theory. The input image feeds into a retinotopic representation of black and white, which compete in a gated dipole circuit. The gated dipole circuit produces complementary after-responses. The black and white information then feeds into edge detection in the BCS, which also contains a gated dipole circuit whose after-responses code orthogonal orientations. The edges in the BCS guide the spread of black and white information in the FCS filling-in stage to limit the spread of color and brightness information.
Mentions: Francis and Rothmayer (2003) and Francis and Schoonveld (2005) reported simulations of Grossberg’s (1994) FACADE model that accounted for the appearance of the afterimage. In this theory, two separate pathways are used to compute visual information. Figure 2 shows a schematic of the major parts of the model. A boundary contour system (BCS) processes boundary or edge information, while a feature contour system (FCS) uses information from the BCS to allow diffusive filling-in of surface properties like color and brightness. The BCS detects oriented edges. The FCS uses the BCS information to determine where information spreads, leading to the final percept.

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.