Action-dependent apparent motion perception

The ability to detect motion is one of the most important properties of our visual system and the visual systems of nearly every other species. Motion perception is not just important for detecting the movement of objects—both for catching prey and for avoiding predators—but it is also important for providing information about the 3-D structure of the world, for maintaining balance, determining our direction of heading, segregating the scene and breaking camouflage, and judging time-to-contact with other objects in the world. ‘Motion perception’ describes the spatio-temporal process of motion perception and the perceptual effects that tell us something about the characteristics of the motion system: apparent motion, the motion after-effect, and induced motion.

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Perceptual Organization in Multistable Apparent Motion

Perception ◽

10.1068/p140135 ◽

1985 ◽

Vol 14 (2) ◽

pp. 135-143 ◽

Cited By ~ 71

Author(s):

Vilayanur S Ramachandran ◽

Stuart M Anstis

Keyword(s):

Motion Perception ◽

Apparent Motion ◽

Perceptual Organization ◽

Necker Cube ◽

The Other ◽

Horizontal Oscillation ◽

Random Location ◽

Single Figure ◽

Looking Back

Is motion perception based on a local piecemeal analysis of the image or do ‘global’ effects also play an important role? Use was made of bistable apparent-motion displays in trying to answer this question. Two spots were flashed simultaneously on diagonally opposite corners of a 1 deg wide square and then switched off and replaced by two spots appearing on the other two corners. One can either see vertical or horizontal oscillation and the display is bistable just as a Necker cube is. If several such bistable figures are randomly scattered on the screen and presented simultaneously, then one usually sees the same motion axis in all of them, suggesting the presence of field-like effects for resolving ambiguity in apparent motion. While viewing a single figure observers experience hysteresis: they tend to adhere to one motion axis or the other and can switch the axis only by looking away and looking back after 10–30 s have elapsed. The figure can be switched off and made to reappear at some other random location on the screen and it is then always found to retain its motion axis. Several such demonstrations are presented to show that spatial induction effects in metastable motion displays may provide a particularly valuable probe for studying ‘laws’ of perceptual organization.

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The Effect of Two-Dimensional and Three-Dimensional Distance on Apparent Motion

Perception ◽

10.1068/p120305 ◽

1983 ◽

Vol 12 (3) ◽

pp. 305-312 ◽

Cited By ~ 12

Author(s):

Kathleen Mutch ◽

Isabel M Smith ◽

Albert Yonas

Keyword(s):

Motion Perception ◽

Apparent Motion ◽

Three Dimensional ◽

Spatial Separation ◽

Three Dimensions ◽

Correspondence Problem ◽

Two Dimensional ◽

Motion Display ◽

Specific Concern ◽

Actual Depth

The problem of how the visual system matches corresponding inputs from one instant to the next to produce the perception of motion has been experimentally examined. The specific concern was whether this correspondence problem is solved prior to the interpretation of three-dimensional distance. Observers judged the degree of apparent motion between pairs of lights in a conflicting motion display. Spatial separation of the lights was varied in two and three dimensions in order to assess whether retinal distance, actual depth, or some combination of these provided critical information for correspondence. The results support Ullman's contention that only two-dimensional (retinal) distances are used in establishing correspondence in motion perception.

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A New Experimental Paradigm for the Investigation of the Secondary System of Human Visual Motion Perception

Perception ◽

10.1068/p020167 ◽

1973 ◽

Vol 2 (2) ◽

pp. 167-180 ◽

Cited By ~ 17

Author(s):

C Lamontagne

Keyword(s):

Computational Model ◽

Motion Perception ◽

Apparent Motion ◽

Visual Motion ◽

Experimental Paradigm ◽

Secondary System ◽

Visual Motion Perception ◽

New Family ◽

The Subject ◽

Object Relative

An experimental paradigm is derived from a computational model of visual motion perception. The new family of phenomena that support this paradigm is presented in the context of the model. The basic phenomenon can be considered as being the apparent motion and the sustained eyetracking of a physically still object (relative to the subject) in the absence of any other object moving relative to the subject.

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