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Journal of the Optical Society of America A

Journal of the Optical Society of America A


  • Vol. 20, Iss. 8 — Aug. 1, 2003
  • pp: 1461–1471

Factors affecting motion integration

Gunter Loffler and Harry S. Orbach  »View Author Affiliations

JOSA A, Vol. 20, Issue 8, pp. 1461-1471 (2003)

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The perceived direction of motion of a featureless contour inside a circular aperture is always perpendicular to the contour’s orientation, regardless of its true motion (the aperture problem). This study investigates the circumstances under which unambiguous feature motion (of line terminators, single dots, or truncations of a D6 pattern) in adjacent apertures can alter the perceived direction of such featureless contours. We find that integration mechanisms responsible for motion capture are fairly robust against misorientations and contrast manipulations of individual components, are sensitive to differences in spatial frequencies, and scale with pattern size. Motion capture is not diminished when a D6 profile is substituted for the square-pulse profile of a line and is independent of the visibility of the apertures, indicating that object interpretations and three-dimensional analyses of a scene are less important than has been postulated previously. These results have strong implications for the neuronal hardware underlying the integration of motion signals across space and provide a framework for global motion models.

© 2003 Optical Society of America

OCIS Codes
(330.4150) Vision, color, and visual optics : Motion detection
(330.5380) Vision, color, and visual optics : Physiology
(330.7310) Vision, color, and visual optics : Vision

Original Manuscript: May 14, 2002
Revised Manuscript: August 7, 2002
Manuscript Accepted: August 7, 2002
Published: August 1, 2003

Gunter Loffler and Harry S. Orbach, "Factors affecting motion integration," J. Opt. Soc. Am. A 20, 1461-1471 (2003)

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  1. This paper is concerned with motion in the two-dimensional frontoprallel plane; the term “rigidity” (or coherence) describes the perception of a single rigid object moving in this plane.
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