This bulletin explains some of the visual characteristics of children and youth, examines critically the vision screening tests used in some schools, and explains the problems resulting from their use. Chapters deal in turn with vision and visual characteristics, the professional eye examination, visual screening tests, problems in referrals from…

In 73 children (6-13 years old) with reading difficulty, ophthalmological evaluation showed that 18 had overt refractive errors, 18 dyslexia and no ocular anomalies, and 37 impaired fusional amplitudes, 24 of whom were dyslexic. In all Ss with poor fusional amplitudes the reading mechanism could be improved with orthoptic exercises. (Author/CL)

Describes an experiment revealing a visual latency effect produced by the wearing of sunglasses. (SL)

The interview with G. N. Getman, a developmental optometrist specializing in learning problems and disabilities, focuses on vision's impact on learning, the role of the vision specialist in the remediation of learning problems and disabilities, early screening programs, and visual training programs. (DLS)

A discription of teaching activities and seeing distances makes it easier to prescribe correct lenses. (AP)

During the next 25 years, the number of Americans over age 65 is expected to reach 50 million. Although many will not experience age-related visual impairments until the age of 60 or 70, some will begin to experience serious problems by the age of 40. The types of vision problems experienced by individuals as they age include difficulty in…

Shows that the perceived shade of gray depends on the luminance relationship between surfaces perceived to be in the same plane and not between surfaces that are merely adjacent in the retinal image. This implies that lateral inhibition cannot explain lightness constancy. (MLH)

Rod-isolation techniques show that light-adapted human rods detect flicker frequencies as high as 28 hertz, and that the function relating rod critical flicker frequency to stimulus intensity contains two distinct branches. (MLH)

Discusses neural activity and stimulation crucial in fetal brain development and the formation of the mind. Focuses on activity-dependent remodeling related to development of the visual system and retinal activity. (MCO)

The role of occlusion configurations in binocular vision was studied in 4 experiments with 10 adult observers. Results reveal that occlusion relationships are sensed during the earliest stages of binocular processing. A simple theoretical framework that unifies fusion, stereopsis, and occlusion is advanced. (SLD)

Stabilization of the retinal image of the boundary between a pair of red/green or yellow/blue stripes, but not their outer edges, results in the entire region being perceived simultaneously as both red/green or yellow/blue. This suggests that the percepts of reddish-green/yellowish-blue apparently are possible in corticocortical color vision…

Teachers need to watch for hidden visual problems which may affect their students' learning. The article discusses vision and learning, visual efficiency problems, and treatment; it describes conditions and symptoms of visual processing and efficiency disorders. (SM)

What shade of gray a surface appears is related to the perceived distribution of light and shadow, which in turn depends on the perceived spatial relation between the surface and its neighbors. (Author/ BB)