Simple discriminations are involved in many functional skills; additionally, they are components of conditional discriminations (identity and arbitrary matching-to-sample), which are involved in a wide array of other important performances. Many individuals with severe disabilities have difficulty acquiring simple discriminations with standard…

Learning centers are a highly regarded and widely accepted practice in early childhood classrooms. Centers offer a variety of experiences during a single time segment that encourage children to explore materials, interact with peers, and accomplish new tasks. In this article, the author presents the block center, a popular mainstay among learning…

Reports effects of context that are entirely perceptual. Visual discrimination was enhanced when line segments were flashed in a region that was perceived as a figure. Discrimination was substantially degraded when the same region was seen as ground although the physical stimulus remained identical throughout figure-ground reversals. (Author/JN)

The article discusses the rationale for a program to develop efficiency in visual functioning for low vision individuals. Detailed identification of all visual functions necessary for maximum efficiency, along with specification of visual tasks related to developmental milestones are charted. (Author/PHR)

This article discusses the increasing incidence of cortical visual impairments, resulting from medical advancements making possible the survival of critically ill children with severe brain damage. Discussed are the prevalence of multiple handicaps, formation of visual concepts, foreground/background distinction, potential for mainstreaming, use…

Meaningful visual experience requires computations that identify objects as the same persisting individuals over time, motion, occlusion, and featural change. This article explores these computations in the tunnel effect: When an object moves behind an occluder, and then an object later emerges following a consistent trajectory, observers…

This article examines how the human visual system represents the shapes of 3-dimensional (3D) objects. One long-standing hypothesis is that object shapes are represented in terms of volumetric component parts and their spatial configuration. This hypothesis is examined in 3 experiments using a whole-part matching paradigm in which participants…

An 18-item "Shortened Visuospatial Questionnaire" (SVS) was validated twice, first by verifying that children (ages 8-13) identified with the SVS questionnaire as having visuospatial learning disability (VSLD) (n=54) actually showed visuospatial deficits on psychometric evaluation, and second, by rating with the SVS a clinically identified…

The generalized optic acceleration cancellation (GOAC) theory of catching proposes that the path of a fielder running to catch a ball is determined by the attempt to satisfy 2 independent constraints. The 1st is to keep the angle of elevation of gaze to the ball increasing at a decreasing rate. The 2nd is to control the rate of horizontal rotation…

Although the role of memory in visual search is debatable, most researchers agree with a limited-capacity model of memory in visual search. The authors demonstrate the role of memory by replicating previous findings showing that visual search is biased away from old items (previously examined items) and toward new items (nonexamined items).…

Images express meaning through particular configurations of visual concepts. A distinguishing feature of discipline based art education is the use of visual imagery to transmit meaning to students. Discipline based art education incorporates concepts and skills from aesthetics, art criticism, art history, and art production and presents a unique…

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)

Six curriculum-based measures of math performance were developed for use with 4-year old preschool children. Measures included counting objects, selecting numbers, naming numbers, selecting shapes, counting, and visual discrimination. Technical properties of probe scores were assessed in two rural public preschool programs. Alternate forms,…

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…

Children often perseverate, repeating prior behaviors when inappropriate. This work tested the roles of verbal labels and stimulus novelty in such perseveration. Three-year-old children sorted cards by one rule and were then instructed to switch to a second rule. In a basic condition, cards had familiar shapes and colors and both rules were stated…