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Michael Kubovy

Publications and source records attributed to Michael Kubovy.

4 recordsLinked to original sources

On the surprising salience of curvature in grouping by proximity.

The authors conducted 3 experiments to explore the roles of curvature, density, and relative proximity in the perceptual organization of ambiguous dot patterns. To this end, they developed a new family of regular dot patterns that tend to be perceptually grouped into parallel contours, dot-sampled structured grids (DSGs). DSGs are similar to the dot lattices used to study grouping by proximity, except that only one of the potential organizations is rectilinear; the others are curvilinear. The authors used the method of M. Kubovy and J. Wagemans (1995) to study grouping by proximity in DSGs. They found that in the competition between the most likely organizations, one rectilinear and the other curvilinear, the latter is more salient. This phenomenon cannot be explained by contemporary accounts of grouping by proximity or contour integration.

Adult↗

Stability and change in perception: spatial organization in temporal context.

Perceptual multistability has often been explained using the concepts of adaptation and hysteresis. In this paper we show that effects that would typically be accounted for by adaptation and hysteresis can be explained without assuming the existence of dedicated mechanisms for adaptation and hysteresis. Instead, our data suggest that perceptual multistability reveals lasting states of the visual system rather than changes in the system caused by stimulation. We presented observers with two successive multistable stimuli and found that the probability that they saw the favored organization in the first stimulus was inversely related to the probability that they saw the same organization in the second. This pattern of negative contingency is orientation-tuned and occurs no matter whether the observer had or had not seen the favored organization in the first stimulus. This adaptation-like effect of negative contingency combines multiplicatively with a hysteresis-like effect that increases the likelihood of the just-perceived organization. Both effects are consistent with a probabilistic model in which perception depends on an orientation-tuned intrinsic bias that slowly (and stochastically) changes its orientation tuning over time.

Adaptation, Physiological↗

Perceived complexity and the grouping effect in band patterns.

Symmetry properties have been shown to determine the perceived complexity of certain patterns. We used a paired-comparison method to obtain judgments of relative complexity for a family of two-dimensional regular patterns called band patterns. Although the complexity of these patterns is well predicted by their symmetry properties we were unable to explain an interaction observed between two of these properties for our experimental patterns. We discuss the implications of our results for two predominant approaches to the perceived complexity of patterns. Neither approach takes into account that the presence of grouping sometimes makes it difficult to perceive a relationship within the pattern that would--were it not for the grouping--simplify it. We conclude that grouping can mask simplicity and that this phenomenon is crucial to the understanding of perceived complexity.

Form Perception↗