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A theory of moving form perception: Synergy between masking, perceptual grouping, and motion computation in retinotopic and non-retinotopic representations.

Oğmen H - Adv Cogn Psychol (2008)

Bottom Line: Based on this duration of visible persistence, we would expect moving objects to appear highly blurred.However, in human vision, objects in motion typically appear relatively sharp and clear.We suggest that clarity of form in dynamic viewing is achieved by a synergy between masking, perceptual grouping, and motion computation across retinotopic and non-retinotopic representations.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical & Computer Engineering, Center for Neuro-Engineering & Cognitive Science, University of Houston, Houston, TX 77204-4005 USA.

ABSTRACT
Because object and self-motion are ubiquitous in natural viewing conditions, understanding how the human visual system achieves a relatively clear perception for moving objects is a fundamental problem in visual perception. Several studies have shown that the visible persistence of a briefly presented stationary stimulus is approximately 120 ms under normal viewing conditions. Based on this duration of visible persistence, we would expect moving objects to appear highly blurred. However, in human vision, objects in motion typically appear relatively sharp and clear. We suggest that clarity of form in dynamic viewing is achieved by a synergy between masking, perceptual grouping, and motion computation across retinotopic and non-retinotopic representations. We also argue that dissociations observed in masking are essential to create and maintain this synergy.

No MeSH data available.


Related in: MedlinePlus

A space-time depiction of the Ternus-Pikler stimulus. For simplicity, one						dimensional space is used and the offset and straight Verniers are indicated						by triangle and circle symbols. A variety of spatio-temporally oriented						receptive fields are superimposed on the stimulus. While the mechanism shown						by solid red contour integrates Vernier information in accordance with the						results shown in Fig. 11, the rest of the mechanisms, shown by dashed blue						contours integrate in a way inconsistent with the data.
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Figure 13: A space-time depiction of the Ternus-Pikler stimulus. For simplicity, one dimensional space is used and the offset and straight Verniers are indicated by triangle and circle symbols. A variety of spatio-temporally oriented receptive fields are superimposed on the stimulus. While the mechanism shown by solid red contour integrates Vernier information in accordance with the results shown in Fig. 11, the rest of the mechanisms, shown by dashed blue contours integrate in a way inconsistent with the data.

Mentions: Results in Fig. 12A and B support the predictions of grouping based non-retinotopic feature perception hypothesis. Not only does this experiment [additional data in (Öğmen, Otto, & Herzog, 2006)] show non-retinotopic feature perception but it also highlights that grouping operations are critical in establishing the mappings from retinotopic to non-retinotopic space. A depiction of our stimulus in a space (horizontal axis) time (vertical axis) diagram is shown in Fig. 13. For simplicity a one-dimensional space is used. The circles and the triangle represent the spatial positions of the straight and offset (probe) Verniers, respectively. The Ternus-Pikler stimulus will activate a large number of integrative mechanisms, some of which are shown superimposed on the stimulus. To explain our data, only an exclusive subset of these mechanisms – specific to the spatial locus and to the prevailing grouping relation (shown by the solid line in the figure) can be in operation. The remaining mechanisms (shown by dashed lines) will integrate information in a manner inconsistent with our data. The oriented receptive-field and the shifter circuit models show two major deficiencies in explaining these data. First, because they do not take into account grouping mechanisms, they will integrate the Vernier information in multiple (inappropriate) ways following the activation of multiple motion detectors. Second, because they lack proper metacontrast mechanisms, they cannot predict when and how motion blur will be curtailed (Section “Motion deblurring in human vision”).


A theory of moving form perception: Synergy between masking, perceptual grouping, and motion computation in retinotopic and non-retinotopic representations.

Oğmen H - Adv Cogn Psychol (2008)

A space-time depiction of the Ternus-Pikler stimulus. For simplicity, one						dimensional space is used and the offset and straight Verniers are indicated						by triangle and circle symbols. A variety of spatio-temporally oriented						receptive fields are superimposed on the stimulus. While the mechanism shown						by solid red contour integrates Vernier information in accordance with the						results shown in Fig. 11, the rest of the mechanisms, shown by dashed blue						contours integrate in a way inconsistent with the data.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2864981&req=5

Figure 13: A space-time depiction of the Ternus-Pikler stimulus. For simplicity, one dimensional space is used and the offset and straight Verniers are indicated by triangle and circle symbols. A variety of spatio-temporally oriented receptive fields are superimposed on the stimulus. While the mechanism shown by solid red contour integrates Vernier information in accordance with the results shown in Fig. 11, the rest of the mechanisms, shown by dashed blue contours integrate in a way inconsistent with the data.
Mentions: Results in Fig. 12A and B support the predictions of grouping based non-retinotopic feature perception hypothesis. Not only does this experiment [additional data in (Öğmen, Otto, & Herzog, 2006)] show non-retinotopic feature perception but it also highlights that grouping operations are critical in establishing the mappings from retinotopic to non-retinotopic space. A depiction of our stimulus in a space (horizontal axis) time (vertical axis) diagram is shown in Fig. 13. For simplicity a one-dimensional space is used. The circles and the triangle represent the spatial positions of the straight and offset (probe) Verniers, respectively. The Ternus-Pikler stimulus will activate a large number of integrative mechanisms, some of which are shown superimposed on the stimulus. To explain our data, only an exclusive subset of these mechanisms – specific to the spatial locus and to the prevailing grouping relation (shown by the solid line in the figure) can be in operation. The remaining mechanisms (shown by dashed lines) will integrate information in a manner inconsistent with our data. The oriented receptive-field and the shifter circuit models show two major deficiencies in explaining these data. First, because they do not take into account grouping mechanisms, they will integrate the Vernier information in multiple (inappropriate) ways following the activation of multiple motion detectors. Second, because they lack proper metacontrast mechanisms, they cannot predict when and how motion blur will be curtailed (Section “Motion deblurring in human vision”).

Bottom Line: Based on this duration of visible persistence, we would expect moving objects to appear highly blurred.However, in human vision, objects in motion typically appear relatively sharp and clear.We suggest that clarity of form in dynamic viewing is achieved by a synergy between masking, perceptual grouping, and motion computation across retinotopic and non-retinotopic representations.

View Article: PubMed Central - PubMed

Affiliation: Department of Electrical & Computer Engineering, Center for Neuro-Engineering & Cognitive Science, University of Houston, Houston, TX 77204-4005 USA.

ABSTRACT
Because object and self-motion are ubiquitous in natural viewing conditions, understanding how the human visual system achieves a relatively clear perception for moving objects is a fundamental problem in visual perception. Several studies have shown that the visible persistence of a briefly presented stationary stimulus is approximately 120 ms under normal viewing conditions. Based on this duration of visible persistence, we would expect moving objects to appear highly blurred. However, in human vision, objects in motion typically appear relatively sharp and clear. We suggest that clarity of form in dynamic viewing is achieved by a synergy between masking, perceptual grouping, and motion computation across retinotopic and non-retinotopic representations. We also argue that dissociations observed in masking are essential to create and maintain this synergy.

No MeSH data available.


Related in: MedlinePlus