September 2005
Volume 5, Issue 8
Vision Sciences Society Annual Meeting Abstract  |   September 2005
The role of local position in the detection of contour curvature
Author Affiliations
  • Nicolaas Prins
    Department of Psychology, University of Mississippi
  • Frederick A. A. Kingdom
    McGill Vision Research Unit, McGill University
Journal of Vision September 2005, Vol.5, 466. doi:
  • Views
  • Share
  • Tools
    • Alerts
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Nicolaas Prins, Frederick A. A. Kingdom; The role of local position in the detection of contour curvature. Journal of Vision 2005;5(8):466. doi:

      Download citation file:

      © ARVO (1962-2015); The Authors (2016-present)

  • Supplements

Aim. Several models of curvature detection assume that curvature is detected by mechanisms that compare local luminance-defined orientations along the contour. Here, we tested the alternative notion that the inputs to curvature detection mechanisms are local contour positions. Method. Contours consisted of strings of oriented Gabor elements with various curvature frequencies. The curvature of the contour could be defined in terms of Gabor position, Gabor orientation, or both. In the position-only condition Gabor orientation was constant, and in the orientation-only condition the Gabor positions formed a straight line. In a 2-IFC procedure subjects were to determine which of two contours was curved. Threshold curvature amplitudes were determined for each of the three conditions. Results. Curvature amplitude thresholds were similar for the position-only and position-and-orientation conditions. However, thresholds were elevated for the orientation-only condition, especially at low curvature frequencies. Conclusion. Our results suggest that the inputs to contour curvature mechanisms are the positions of local contrast-energy along the contour, with little or no input from luminance-defined orientations, particularly at low curvature frequencies.

Prins, N. Kingdom, F. A. A. (2005). The role of local position in the detection of contour curvature [Abstract]. Journal of Vision, 5(8):466, 466a,, doi:10.1167/5.8.466. [CrossRef] [PubMed]
 Supported by NSERC (Canada) grant OGP 0121713 given to F.K.

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.