Purpose: This research examined how the color distribution of symbols within a visual aided augmentative and alternative communication array influenced the speed and accuracy with which participants with and without Down syndrome located a target picture symbol. Method: Eight typically developing children below the age of 4 years, 8 typically…

Many everyday matching tasks taught to persons with developmental disabilities are visual-visual non-identity matching (VVNM) tasks, such as matching the printed word DOG to a picture of a dog, or matching a sock to a shoe. Research has shown that, for participants who have failed a VVNM prototype task, it is very difficult to teach them various…

A theory on the features of a visual scene and how these features are organized to provide a representational model of the visual scene is presented. (HB)

The latency at which objects could be identified by 126 subjects was compared through line drawings (edge-based) or color photography (surface depiction). The line drawing was identified about as quickly as the photograph; primal access to a mental representation of an object can be modeled from an edge-based description. (SLD)

Three experiments on tachistoscopic perception of visual stimuli demonstrate that the visual system is sensitive to global topological properties. The results indicate that extraction of global topological properties is a basic factor in perceptual organization. (Author)

Recent studies have suggested that children with autism perform better than matched controls on visual search tasks and that this stems from a superior visual discrimination ability. This study assessed whether these findings generalize from children to adults with autism. Experiments 1 and 2 showed that, like children, adults with autism were…

Infants five- and seven-months-old were sequentially shown three stimulus arrays of visual elements, only one of which was capable of producing subjective contours. An infant habituation control procedure was used to test infants' abilities to discriminate the arrays. (Author/RH)

Four experiments examined the ability of infants to form categorical representations for the spatial relations "above" and "below." Found that three- and four-month-olds could form categorical representations for above and below when a diamond-shape was presented above or below a horizontal bar but could not do so when a number…

The authors used visual search tasks in which components of the classic flanker task (B. A. Eriksen & C. W. Eriksen, 1974) were introduced. In several experiments the authors obtained evidence of parallel search for a target among distractor elements. Therefore, 2-stage models of visual search predict no effect of the identity of those…

Previous research has shown that the appearance of task-irrelevant abrupt onsets influences saccadic eye movements during visual search and may slow down manual reactions to target stimuli. Analysis of reaction time distributions in the present study offers evidence suggesting that top-down inhibition processes actively suppress oculomotor or…