August 2016
Volume 16, Issue 12
Open Access
Vision Sciences Society Annual Meeting Abstract  |   September 2016
Sensitivity to horizontal and vertical sine-wave corrugations defined by binocular disparity: factor analysis of individual differences reveals discrete processes with broad orientation and spatial frequency tuning
Author Affiliations
  • Jenny Read
    Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
  • Ignacio Serrano-Pedraza
    Universidad Complutense de Madrid, Madrid, Spain
  • Michael Widdall
    Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
  • David Peterzell
    John F. Kennedy University, USA
Journal of Vision September 2016, Vol.16, 833. doi:10.1167/16.12.833
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Jenny Read, Ignacio Serrano-Pedraza, Michael Widdall, David Peterzell; Sensitivity to horizontal and vertical sine-wave corrugations defined by binocular disparity: factor analysis of individual differences reveals discrete processes with broad orientation and spatial frequency tuning. Journal of Vision 2016;16(12):833. doi: 10.1167/16.12.833.

      Download citation file:


      © 2017 Association for Research in Vision and Ophthalmology.

      ×
  • Supplements
Abstract

Sensitivity functions for horizontally- and vertically-oriented depth corrugations both peak in modulation spatial frequency at 0.2-0.4 cycles/degree, with higher sensitivity for horizontal than vertical corrugations (both defined by horizontal disparities). In order to elucidate the spatial frequency and orientation tuning of underlying processes, we analyzed two data sets using factor analytic techniques developed to estimate the number and tuning of spatial channels (Peterzell et al.,1993; 1995; 1996; 2000). The first set (Widdall et al., unpublished; 16 deg displays, n=30 individuals), was for 0.1, 0.2, 0.4, 0.8, and 1.4 (1.2 or 1.6) cycles/degree. A principal component analysis of disparity sensitivities (log arc sec) determined that two significant factors accounted for 70% of the variability. Following Varimax rotation to approximate "simple structure," one factor clearly loaded on to low spatial frequencies (0.4 c/deg and below), while the second was tuned to higher spatial frequencies (0.8 and 1.4 c/deg). Both factors had nearly identical tuning for horizontal and vertical patterns. In a second very small data set (Bradshaw & Rodgers, 1999; 20 degree displays, n=6 individuals), two or three factors accounted for 89% or 96% of the variability, with just one factor underlying the horizontal data, and at least two factors underlying the vertical data. The finding of separate factors for low and high spatial frequencies are consistent with previous studies (Witz & Hess, 2013; Serrano-Pedraza et al., 2013). The failure to find separate factors for horizontal and vertical corrugations in the larger data-set is surprising. Individuals' sensitivity to horizontal and vertical gratings were highly correlated at most spatial frequencies, even though the neuronal mechanisms are believed to be different, suggesting that sensitivity is limited mainly by the initial encoding of disparity.

Meeting abstract presented at VSS 2016

×
×

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.

×