Contour integration across polarities and spatial gaps: from local contrast filtering to global grouping - Archive ouverte HAL Access content directly
Journal Articles Vision Research Year : 1997

Contour integration across polarities and spatial gaps: from local contrast filtering to global grouping

(1) , (2)
1
2

Abstract

This article introduces an experimental paradigm to selectively probe the multiple levels of visual processing that influence the formation of object contours, perceptual boundaries, and illusory contours. The experiments test the assumption that, to integrate contour information across space and contrast sign, a spatially short-range filtering process that is sensitive to contrast polarity inputs to a spatially long-range grouping process that pools signals from opposite contrast polarities. The stimuli consisted of thin subthreshold lines, flashed upon gaps between collinear inducers which potentially enable the formation of illusory contours. The subthreshold lines were composed of one or more segments with opposite contrast polarities. The polarity nearest to the inducers was varied to differentially excite the short-range filtering process. The experimental results are consistent with neurophysiological evidence for cortical mechanisms of contour processing and with the Boundary Contour System model, which identifies the short-range filtering process with cortical simple cells, and the long-range grouping process with cortical bipole cells.
Not file

Dates and versions

hal-02168844 , version 1 (29-06-2019)

Identifiers

  • HAL Id : hal-02168844 , version 1
  • PUBMED : 9156188

Cite

Birgitta Dresp, S Grossberg. Contour integration across polarities and spatial gaps: from local contrast filtering to global grouping. Vision Research, 1997, 37 (7), pp.913-24. ⟨hal-02168844⟩
12 View
0 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More