Coherent motion perception fails at low contrast.

Delicato, L.S. and Derrington, A.M. (2005) Coherent motion perception fails at low contrast. Vision Research, 45 (17). pp. 2310-2320. ISSN 0042-6989 . (The full text of this publication is not available from this repository)

The full text of this publication is not available from this repository. (Contact us about this Publication)
Official URL
http://www.sciencedirect.com/science?_ob=ArticleUR...

Abstract

If the Fourier components of a moving plaid have similar temporal frequency, spatial frequency and contrast, coherent motion is perceived according to subjective judgements. We have devised a more objective method of determining the conditions required for coherent motion. Moving plaid stimuli were created with one stationary component. Plaids with a stationary component always have a single perceived direction of motion, which is determined by the presence or absence of coherent motion. In a temporal two-interval forced-choice paradigm we used a direction discrimination task to investigate the effect of varying the temporal and spatial characteristics of the Fourier components and pattern contrast on the probability of coherent motion perception. Agreement across observers regarding the conditions required for coherent motion was excellent using this more objective method. We find that patterns do not produce coherent motion when presented at contrast threshold, irrespective of how similar the Fourier components are. We also confirm that when the temporal frequency, spatial frequency and contrast of the gratings are sufficiently similar, observers report the direction of motion indicating coherent motion.

Item Type: Article
Uncontrolled keywords: coherence; contrast; motion; plaid
Subjects: B Philosophy. Psychology. Religion > BF Psychology
Divisions: Faculties > Social Sciences > School of Psychology
Depositing User: Ros Beeching
Date Deposited: 11 Jun 2008 13:21
Last Modified: 14 Jan 2010 14:15
Resource URI: http://kar.kent.ac.uk/id/eprint/4218 (The current URI for this page, for reference purposes)
  • Depositors only (login required):