Ralph J. Roberts

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A neuropsychological approach was used to examine the frontal lobe and right parietal lobe theories of attention deficit hyperactivity disorder (ADHD). Considerable attempts were made to select as pure a group of ADHD boys as possible. The performance of 10-14-year-old ADHD boys (n = 22), both on and off stimulant medication, was compared with the(More)
This study explored whether functional properties of the hand and tools influence the allocation of spatial attention. In four experiments that used a visual-orienting paradigm with predictable lateral cues, hands or tools were placed near potential target locations. Results showed that targets appearing in the hand's grasping space (i.e., near the palm)(More)
Spatial attention can be biased to locations near the hand. Some studies have found facilitated processing of targets appearing within hand-grasping space. In this study, we investigated how changing top-down task priorities alters hand bias during visual processing. In Experiment 1, we used a covert orienting paradigm with nonpredictive cues and emphasized(More)
Research confirms that the body influences perception, but little is known about the embodiment of attention. We investigated whether the implied actions of others direct spatial attention, using a lateralized covert-orienting task with nonpredictive central cues depicting static, right/left-facing bodies poised in midaction. Validity effects (decreased(More)
Research on spatial attention traditionally focuses on how it is influenced by the location of objects within the visual environment. However, a primary function of spatial attention is to plan physical actions. When events occur in the world, visual information needs to be integrated with current body position to help prepare effective responses to these(More)
Our trunks influence where we perform actions in space. Thus, trunk direction may define a region of spacethat is accorded special treatment by the attention system. We investigated conditions under which a trunk orientation bias for attention might be relevant for healthy adults. Three experiments compared visual detection performance for participants(More)
The spatial referents "left" and "right" are one of the most common means for specifying direction and location, yet little is known about the processes that underlie the use of these concepts. Two studies tested the hypothesis that children and adults who correctly identify left-right directions from nonoccupied orientations perform imagined rotations to(More)
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