September 2015
Volume 15, Issue 12
Free
Vision Sciences Society Annual Meeting Abstract  |   September 2015
DETECTION OF ORIENTATION-DEFINED BOUNDARIES IS JUST AS INEFFICIENT AS ESTIMATION OF MEAN ORIENTATION
Author Affiliations
  • Joshua Solomon
    Centre for Applied Vision Sciences, City University London
  • Michael Morgan
    Centre for Applied Vision Sciences, City University London Max-Planck Institute for Metabolism
Journal of Vision September 2015, Vol.15, 773. doi:10.1167/15.12.773
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Joshua Solomon, Michael Morgan; DETECTION OF ORIENTATION-DEFINED BOUNDARIES IS JUST AS INEFFICIENT AS ESTIMATION OF MEAN ORIENTATION. Journal of Vision 2015;15(12):773. doi: 10.1167/15.12.773.

      Download citation file:


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

      ×
  • Supplements
Abstract

When compared with other summary statistics (mean size, size variance, orientation variance), visual estimates of average orientation are inefficient. Observers act as if they use information from no more than two or three items. We hypothesised that observers would attain greater sampling efficiency when their task did not require an explicit representation of mean orientation. To test this hypothesis, we presented two arrays of 32 Gabor patterns each; one left and one right of fixation. Orientations in the target array were sampled from Wrapped Normal distributions having two different means. One distribution defined orientations above the horizontal meridian, the other defined orientations below the meridian. All orientations in the other array were defined by a single Wrapped Normal distribution having the same variance. Contrary to our hypothesis, model fits indicate that observers effectively ignored all but one item from the top and bottom of each array. In fact, we found no change in the threshold difference between the target's two means when all but one item from the top and bottom of each array were removed. We are forced to conclude that the visual system does not compute the average of more than a few orientations, even for texture segmentation.

Meeting abstract presented at VSS 2015

×
×

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.

×