Many computational models of normal vernier acuity make predictions based on the just-noticeable contrast difference. Recently, Hu, Klein and Carney [(1993) Vision Research, 33, 1241-1258] compared vernier acuity and contrast discrimination (jnd) in normal foveal viewing using cosine gratings. In the jnd stimulus the test grating was added in-phase to the (sinusoidal) pedestal, whereas in the v...

PURPOSE To measure achromatic spatial contrast sensitivity in patients with anisometropic amblyopia under conditions favoring inferred parvocellular (PC) or magnocellular (MC) pathway mediation. METHODS Fourteen anisometropic amblyopes (VA amblyopic eye 6/12 or lower; better eye greater than 6/7.5) and 10 age-matched, nonamplyopic controls (VA 6/6) participated. Foveal spatial contrast sensit...

Neurologically normal observers show a consistent leftward bias when asked to bisect a horizontal line ("pseudoneglect"). In this study, we found that subjects with strabismic and strabismic-anisometropic amblyopia show a consistent rightward bias ("minineglect") in a line bisection task. The bias was seen in both eyes, but affected more strongly the amblyopic eye. Purely anisometropic amblyope...

purpose : to determine the prevalence of amblyopia and strabismus in the schoolchildren of the city of bojnourd, iran methods : in 2010, randomized stratified cluster sampling was employed in a cross-sectional study on primary and junior high schoolchildren. all the examinations were performed in schools. all students received refraction, vision and subjective refraction tests. the cover test w...

Traditional treatment of amblyopia, although still in use and of great value, has recently been challenged by data from studies relative to efficacy of different modalities and regimens of therapy. LogMAR-based acuity charts should be used, whenever possible, for diagnosis and monitoring. Refractive errors of certain magnitude should be prescribed, and correction worn for at least 4 months befo...

BACKGROUND Steady-state pattern electroretinogram (PERG) and frequency doubling technology (FDT) perimetry can be used to selectively investigate the activity of the M-Y ganglion cells in adult anisometropic amblyopes. METHODS Fifteen normal subjects (mean 27.8±4.1 years) and 15 adults with anisometropic amblyopia (mean 28.7±5.9 years) were analyzed using steady-state PERG and FDT. RESULTS ...

Recent studies have demonstrated that training adult amblyopes in simple visual tasks leads to significant improvements of their spatial vision. One critical question is: How much can training with one particular stimulus and task generalize to other stimuli and tasks? In this study, we estimated the bandwidth of perceptual learning in teenage and adult observers with anisometropic amblyopia an...

. To investigate the effect of anisometropic and strabismic amblyopia on the nerve fiber layer thickness. This cross-sectional study was done on 54 amblyopic subjects, equally in both strabismic and anisometropic groups. The thickness otonerve fiber layer measured in superior, inferior, nasal, temporal quadrants and as a whole in both eyes of both groups. The means of thickness were compared in...

PURPOSE To determine the nature and limits of visual improvement through repetitive practice in human adults with naturally occurring amblyopia. METHODS A key measure the authors used was a psychophysical estimate of Vernier acuity; persons with amblyopia have marked deficits in Vernier acuity that are highly correlated with their loss of Snellen acuity. The experiment consisted of three phas...