Detection, discrimination and integration of second-order orientation information in strabismic and anisometropic amblyopia

Vision Res. 2005 Aug;45(18):2449-60. doi: 10.1016/j.visres.2005.02.018. Epub 2005 Apr 7.

Abstract

To better understand the nature of the cortical deficit in amblyopia we undertook a systematic investigation of second-order processing in 8 amblyopic and 8 normal observers. We investigated local detection, discrimination and global integration. Our local stimulus consisted of a Gaussian patch of fractal noise multiplied by a 1-d sinusoidal modulator. Our global stimulus consisted of an array of such elements. We revealed second-order detection deficits for stimuli with equi-visible carriers. Orientation discrimination for an isolated second-order patch was comparable in normal and amblyopic eyes. We showed that pure integration of second-order patterns can be normal in amblyopia.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Amblyopia / physiopathology*
  • Contrast Sensitivity / physiology
  • Discrimination, Psychological / physiology
  • Humans
  • Middle Aged
  • Orientation / physiology*
  • Photic Stimulation / methods
  • Psychophysics
  • Sensory Thresholds / physiology
  • Strabismus / physiopathology*
  • Visual Cortex / physiopathology