November 2004
Volume 4, Issue 11
Free
OSA Fall Vision Meeting Abstract  |   November 2004
Dichoptic difference thresholds for the properties of chromatic stimuli
Author Affiliations
  • Gokhan Malkoc
    McGill University, Montreal, Quebec, CANADA
  • Frederick A. A. Kingdom
    McGill University, Montreal, Quebec, CANADA
Journal of Vision November 2004, Vol.4, 64. doi:10.1167/4.11.64
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Gokhan Malkoc, Frederick A. A. Kingdom; Dichoptic difference thresholds for the properties of chromatic stimuli. Journal of Vision 2004;4(11):64. doi: 10.1167/4.11.64.

      Download citation file:


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

      ×
  • Supplements
Abstract

We have investigated the properties of binocular colour vision mechanisms using a new measure; the dichoptic colour difference threshold (DCDT). The DCDT is the minimal detectable difference in colour between two dichoptically superimposed stimuli. We examined DCDTs in order to determine the dependency on a) the average colour and b) the colour contrast of the stimuli. The stimuli consisted of two, vertically separated, 4.57-deg diameter, equiluminant, circular colour patches. Both were stereo-pairs presented via a modified Wheatstone stereoscope. In one of the stereo-pairs, there was a between-eye difference in colour whereas the colours of the other stereo-pair were same for both eyes. Subjects had to decide which of the two stimuli was different in colour. Psychometric functions were fitted to the data and used to calculate thresholds for DCDTs. We found that DCDTs were higher than monocular colour difference thresholds and lower than binocular rivalry thresholds (dichoptically superimposed colours seen in alternation). DCDTs were found to be between 10 and 20 deg for test colours, and there were no apparent minima at points intermediated between either of cardinal colors or unique hues. DCDTs were significantly and positively correlated with perceived colour difference suggesting that perceived color difference plays a significant factor for DCDTs. Thus, in contrast to previous findings, our DCDTs data cannot be explained in terms of a limited number of mechanisms sensitive to either the cardinal colours or unique hues, suggesting that multiple binocular colour vision mechanisms exist at the post-receptoral level. DCDTs were constant as a function of chromatic contrast (except at very low contrasts) when measured in terms of distance in colour space.

Malkoc, G., Kingdom, F. A. A.(2004). Dichoptic difference thresholds for the properties of chromatic stimuli [Abstract]. Journal of Vision, 4( 11): 64, 64a, http://journalofvision.org/4/11/64/, doi:10.1167/4.11.64. [CrossRef]
Footnotes
 Supported by Canadian Institute of Health Research grant #MOP-11554 awarded to FK.
×
×

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.

×