The underlying mechanism of search asymmetry is still unknown. Many computational models postulate top-down selection of target-defining features as a crucial factor. This feature selection account implies, and other theories implicitly assume, that predefined target identity is necessary for search asymmetry. The authors tested the validity of…

Configural visual abilities in thirteen children with Williams syndrome (WS) compared to 13 children matched on mental age and 13 children matched on chronological age. Configural abilities were tested through four tasks (1) Silhouette (2) Fragmented (3) Mooney and (4) overlapping figures. In the first three tasks, it was necessary to take into…

Three forms of a symbol-digit substitution task were administered to 62 female and 96 male college students. Results support the theory that the superior performance of women over men on the Digit-Symbol Substituion subtest of the Wechsler scales is due to their greater ability to encode symbols verbally. (Author/JAC)

When learning basic color vocabulary, young children show a selective delay in the acquisition of brown and gray relative to other basic color terms. In this study, we first establish the robustness of this finding and then investigate the extent to which perception, language, and color preference may influence color conceptualization.…

We examine the visual processing of high-functioning adults with developmental dyslexia (mean Performance IQ=126.5) and current phonological problems. In comparison to an age- and IQ-matched control group, the group with dyslexia showed deficits in two tasks associated with magnocellular/dorsal pathway function. For the "frequency doubling"…

The effects of age, task, and egocentric responding on visual-spatial perspective taking were studied among 41 preschool children between 3.0 and 5.9 years of age. Children were individually administered three perspective-taking measures: the upside-down/right-side-up task, a block task, and a picture box task, all previously described in the…

A model for sequencing tasks in the area of visual perception was developed. This paper reports an attempt to validate the structure of the model. The performance of 50 normal preschool children on a 47 item test was studied. The results obtained support the use of the model as a framework for developing visual perception tasks. (Author)

The Matching Familiar Figures Test and the Auditory Impulsivity Task were administered to 81 fourth-grade students. Fifty-five percent of the students maintained classifications as reflective, impulsive, fast-accurate, or slow-inaccurate across the two modalities, indicating that the two tasks measured different abilities. The authors suggest that…

Multielement visual tracking and visual search are 2 tasks that are held to require visual-spatial attention. The authors used the attentional operating characteristic (AOC) method to determine whether both tasks draw continuously on the same attentional resource (i.e., whether the 2 tasks are mutually exclusive). The authors found that observers…

Language delay and impairment are salient features of autism. More specifically, there is evidence of atypical semantic organization in autism, but the functional brain correlates are not well understood. The current study used functional MRI to examine activation associated with semantic category decision. Ten high-functioning men with autism…

The current work examined age differences in the classification of novel object images that vary in continuous dimensions of structural shape. The structural dimensions employed are two that share a privileged status in the visual analysis and representation of objects: the shape of discrete prominent parts and the attachment positions of those…

The purpose of the present study was to determine whether playing a specific ball sport, such as tennis, could maintain the coincidence-timing (CT) performance of older adults at a similar level to that of younger ones. To address this question, tennis players and nonplayers of three different age ranges (ages 20-30, 60-70, and 70-80 years)…

Lip movements were examined across several repetitive speaking conditions (speech alone and speaking concurrently with a linguistic, cognitive, or visuomotor challenge task) in 20 young adults. Performance in these nonspeech activities was also compared between isolated tasks and concurrent speech conditions. Linguistic challenges resulted in…

Children (ages 5, 7, and 9 years) and young adults completed two visual attention tasks that required them to make a forced choice identification response to a target shape presented in the center of a computer screen. In the first task (high correlation condition) each target was flanked with the same distracters on 80% of the trials (valid…

The manual is designed to provide a basis for inservice training for replication of components of the MECCA (Make Every Child Capable of Achieving) model, a project designed to develop and implement early identification procedures and prescriptive educational programs for children entering kindergarten with a variety of potential educational…