Timecourse of preshaping for functional responses to objects

The present study explores the unfolding of hand shaping the context of functional responding to common objects. The principal issue addressed by this study is whether distinct, identifiable preshapes are evidenced in preparation for four distinct types of hand contact, including nonprehensile as well as prehensile hand shapes, and for small and large surfaces of contact. All four shapes considered here (poke, pinch, palm and clench) showed evidence of distinct preshaping, with similar timecourses in relation to the onset of reaching. The initial separation of the fingers, formation of first identifiable preshape feature, and completion of the preshape appeared at essentially the same time relative tot he onset of reaching for all four hand shapes. The hand shapes did differ, however, in the time between the completion of a stable preshape and contact with the object. The time for preshape-to-contact was greater for hand shapes with small surfaces of contact than for those with large surfaces and for prehensile shapes than for nonprehensile. These differences are attributed to the precision required for the ultimate object-contact response.     

临床伦理学的未来方向

1　既往史序言本文是描述临床伦理学领域系列文章中的最后一篇。我们在本文中预测临床伦理学若干可能的方向。我们选定为今后 2 0年作些推测———这是一个大致上相等于美国现代生命医学伦理学运动整个历史的时期。在以往 2 0年中 ,生命医学伦理学是跟生物学与医学的革命性发展同步的。其结果是 ,生命医学伦理学在这个时期比它在整个既往历史中变化得更为深刻。今日 ,生命医学伦理学不仅使伦理学家们高度感兴趣 ,而且使我们社会全体都高度感兴趣 ,包括卫生界、公众、法院、媒体及政策制订者。在一个 2 5 0 0年中甚少变化 ,几乎只把它眼光限…     

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Theoretical Medicine and Bioethics -     

Orienting of attention via observed eye gaze is head-centred

Observing averted eye gaze results in the automatic allocation of attention to the gazed-at location. The role of the orientation of the face that produces the gaze cue was investigated. The eyes in the face could look left or right in a head-centred frame, but the face itself could be oriented 90 degrees clockwise or anticlockwise such that the eyes were gazing up or down. Significant cueing effects to targets presented to the left or right of the screen were found in these head orientation conditions. This suggests that attention was directed to the side to which the eyes would have been looking towards, had the face been presented upright. This finding provides evidence that head orientation can affect gaze following, even when the head orientation alone is not a social cue. It also shows that the mechanism responsible for the allocation of attention following a gaze cue can be influenced by intrinsic object-based (i.e. head-centred) properties of the task-irrelevant cue.     

Evaluation of Interactive Computerized Training to Teach Paraprofessionals to Implement Errorless Discrete Trial Instruction

Efficient and effective training strategies for paraprofessionals in special education settings face many challenges. Interactive computerized training (ICT)—a self-paced program that incorporates audio narration, video models, interactive activities, and competency checks—is one potential solution. ICT has been successful in training college students and special education teachers to implement discrete trial instruction (DTI), but its effectiveness to train paraprofessionals is unknown. Using a multiple-baseline design, we evaluated the feasibility of ICT, to train six paraprofessionals to implement DTI with an errorless learning procedure. Following ICT, the fidelity of implementation of DTI increased for all participants when implemented with a student in their classroom; however, competency varied. We added additional training components that progressed from low to more intensive feedback delivered remotely in attempt to increase fidelity to 90% or higher implementation. We also evaluated generalization to novel instructional programs and maintenance of instruction in the absence of feedback.     

Hemisphere differences for components of mental rotation

The hemispheric functional lateralization of components of mental rotation performance was investigated. Twenty right-handed males were presented with rotated alphanumerics and unfamiliar characters in the left or right visual field. Subjects decided if the laterally presented stimulus was identical to or a mirror image of a center standard stimulus. Reaction time and errors were measured. Previous mental rotation findings were replicated and the visual field variable produced significant effects for both dependent measures. An overall right visual field advantage was observed in the latency data, suggesting a left hemisphere superiority for at least one component process of the task. A significant interaction in the error data showed that alphanumerics produced less errors in the right visual field than in the left visual field, consistent with a left hemisphere superiority for processing verbal symbolic material. No such hemispheric difference in accuracy was found for unfamiliar characters.     

Timecourse of Preshaping for Functional Responses to Objects

The present study explores the unfolding of hand shaping in the context of functional responding to common objects. The principal issue addressed by this study is whether distinct, identifiable preshapes are evidenced in preparation for four distinct types of hand contact, including nonprehensile as well as prehensile hand shapes, and for small and large surfaces of contact. All four shapes considered here (poke, pinch, palm and clench) showed evidence of distinct preshaping, with similar timecourses in relation to the onset of reaching. The initial separation of the fingers, formation of first identifiable preshape feature, and completion of the preshape appeared at essentially the same time relative to the onset of reaching for all four hand shapes. The hand shapes did differ, however, in the time between the completion of a stable preshape and contact with the object. The time for preshape-to-contact was greater for hand shapes with small surfaces of contact than for those with large surfaces and for prehensile shapes than for non-prehensile. These differences are attributed to the precision required for the ultimate object-contact response.     

A computer-based test battery for the assessment of static and dynamic spatial reasoning abilities

A battery of 10 computerized tests of spatial ability is described. It includes 5 tests that require reasoning about static spatial displays and 5 tests that require reasoning about dynamically displayed spatial information. An integrated software package for task presentation and data analysis is described, along with a summary of results from a validation study comparing performance on the computer-based tests with performance on standardized paper-and-pencil tests of spatial abilities. Finally, research applications of the current battery are discussed.