Age-related macular degeneration (AMD) is a leading cause of vision loss in Americans aged 60 and older. The loss of central vision from AMD can decrease visual acuity, contrast sensitivity, glare sensitivity, color discrimination, and the ability to adapt to changes in lighting conditions. Older adults with vision loss often have other chronic,…

Vision is the dominant sense, and the eyes are connected with almost every other part of the brain. If the vision system is poorly developed, children trying to learn suffer. Without good up close vision, students are handicapped even if no one knows or suspects it--they may not even know it themselves. Students do not know that the way they see…

The visual acuity of 8 children, aged 2-7, with low vision and multiple handicaps was effectively tested using the Teller Acuity Cards and a preferential-looking procedure with operant modification. This inexpensive procedure was found to be suitable for at-home testing by itinerant vision specialists in developing countries or rural areas. (DB)

Retinitis pigmentosa is a rod-cone dystrophy, commonly genetic in nature. Approximately 60-80% of those with retinitis pigmentosa inherit it by an autosomal recessive transmission (Brilliant, 1999). There have been some reported cases with no known family history. The symptoms of retinitis pigmentosa are decreased acuity, photophobia, night…

The Parsons Visual Acuity Test (PVAT) described in the article has been developed for use with difficult-to-test individuals previously labeled untestable. The studies reported support use of the PVAT as an alternative screening procedure for identifying difficult-to-test persons who are in need of a professional eye examination. (Author/CL)

Understanding vision is not a simple task. Nevertheless, a great deal is known about vision, more than about any of our other senses. The articles collected in this volume were chosen and organized with the intention of providing a survey of a number of different areas of vision research. Three major sections focus on the general categories of…

Techniques used by the Special Visual Assessment Clinic for the Handicapped at the University of California-Berkeley School of Optometry are designed to serve handicapped children and adults generally considered "difficult to assess." This article describes the clinic's assessment goals, clientele, and methods for assessing visual ability and…

Describes Intermittent Central Suppression (ICS), a treatable eye malfunction that can make reading difficult. Reports that some students with ICS are not diagnosed through standard vision acuity tests and are misdiagnosed as learning disabled. Presents a study that found that students who were treated for ICS stayed in school longer than students…

In order to assess vision in Alzheimer's disease, gerontologists must use tests that make minimal cognitive demands on the subject. Using such tests revealed a pattern of deficits in color discrimination, stereoacuity, contrast sensitivity, and backward masking. Impaired vision predicts deficient performance on numerous tests of cognition. (JPS)

Although several vision screening techniques are available for infants, none is routinely used. Visual deficits are often first detected through required preschool vision screenings, which vary in their comprehensiveness. No standardization for testing or administration exists. Some of the testing procedures used may have inappropriately high…

This article describes addition of a "learn a routine" procedure to functional visual assessments of children with severe neurological and physical disabilities. The procedure capitalizes on the child's interest of the moment and provides information on the child's patterns of responses, ability to accommodate to variations of a stimulus, and…

Vision assessment in multiply impaired children (ages 3-19, n=50) was studied by evaluating questionnaires completed by the psychological services responsible for determining their educational requirements. Relatively few conducted assessments of visual functioning but chose instead to determine level of visual impairment from medical,…

Summarizes the anatomical, physiological, and psychological evidence related to the primate visual system. States that comparison of perceptual abilities with the electrophysiological properties of neurons may help deduce functions of visual areas. (RT)

Describes a corrective method of color adaptation designed to allow most, if not all, individuals to participate in the learning process as well as social and work-related environments. Provides a concise summation of facts and theories concerning color deficiency. Includes anatomical drawings, graphs, and statistical data. (MJP)