Visual Dissociations of Movement, Position, and Stereo Depth: Some Phenomenal Phenomena

  title={Visual Dissociations of Movement, Position, and Stereo Depth: Some Phenomenal Phenomena},
  author={R. L. Gregory and Priscilla Heard},
  journal={Quarterly Journal of Experimental Psychology},
  pages={217 - 237}
  • R. Gregory, P. Heard
  • Published 1 February 1983
  • Physics
  • Quarterly Journal of Experimental Psychology
Helmholtz (1867) described as “irradiation” the apparently greater size of a white compared with a dark square, or disc or whatever of the same physical size. The illusory size difference is reversed at low contrasts (Weale, 1974). It is also known that rapid increases in brightness gives apparent movement (gamma movement), though there is no agreed explanation for either phenomenon. When narrow bordering stripes are added, further systematic phenomena occur. With intensity modulation of an… 

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