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941.
This article describes the design and implementation of a multiservice, community-based intervention aimed at promoting the personal and career development of urban, African-American youth.  相似文献   
942.
DSM-based research on comorbidity has suggested thatdepression andpersonality disorder frequently occur together and that the combination of syndromes is associated with a poor response to treatment for depression. The present study was designed to explore the effect of comorbid Axis II pathology for a sample of 45 inpatients who received treatment for major depression. Both categorical and dimensional ratings of personality disorder were used in the statistical analysis. Positive categorical diagnosis of Cluster C (anxious-avoidant) disorder, as well as higher dimensional rating of Cluster A (odd-eccentric) pathology, was predictive of a poor response to treatment (p<.05), as measured by change in pre-post clinical ratings on the Montgomery-Asberg Depression Rating Scale. These results were construed as indicative of a significant Axis II comorbidity effect in the context of an inpatient, multimodal treatment setting for depression. The results also spotlight the influence of techniques of measurement in determining the outcome of statistical analysis.  相似文献   
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A DEVELOPMENTAL DEFICIT IN LOCALIZING OBJECTS FROM VISION   总被引:3,自引:0,他引:3  
Abstract— We describe a college student, A. H., with a developmental deficit in determining the location of objects from vision. The deficit is selective in that (a) localization from auditory or tactile information is intact, (b) A H reports the identity of mislocalized objects accurately, (c) visual localization errors preserve certain parameters of the target location, and (d) visual localization is severely impaired under certain stimulus conditions, but nearly intact under other conditions. These results bear on the representation and processing of location information in the visual system, and also have implications for understanding developmental dyslexia.  相似文献   
946.
GUIDED VISUAL SEARCH IS A LEFT-HEMISPHERE PROCESS IN SPLIT-BRAIN PATIENTS   总被引:1,自引:0,他引:1  
Abstract— Previous research has shown that split-brain (callosotomy) patients search through visual displays twice as fast as normal observers when items are divided evenly between visual hemifields, as though each disconnected hemisphere possessed its own attentional scanning system (Luck, Hillyard, Mangun, & Gazzaniga, 1989, 1994) Results from 3 split-brain patients in the present study indicate that the ability to limit search to a relevant subset of the visual display is lateralized to the left cerebral hemisphere. This ability to perform guided search was not shown in the right hemisphere, even when the search time in that hemisphere was superior to search time in the left Furthermore, guided search was observed for both hemifields in normal control observers. These findings suggest that, as with higher cognitive processes such as language, strategic visuospatial attentional processes are preferentially lateralized to the left cerebral hemisphere. The findings also imply that the callosum mediates guided search in the right hemisphere of normal subjects  相似文献   
947.
GROUPING BY PROXIMITY AND MULTISTABILITY IN DOT LATTICES:   总被引:1,自引:0,他引:1  
Abstract— Gestalt phenomena have long resisted quantification. In the spirit of Gestalt field theory, we propose a theory that predicts the probability of grouping by proximity in the six kinds of dot lattices (hexagonal, rhombic, square, rectangular, centered rectangular, and oblique). We claim that the unstable perceptual organization of dot lattices is caused by competing forces that attract each dot to other dots in its neighborhood. We model the decline of these forces as a function of distance with an exponential decay function. This attraction function has one parameter, the attraction constant Simple assumptions allow us to predict the entropy of the perceptual organization of different dot lattices. We showed dot lattices tachistoscopically to 7 subjects, and from the probabilities of the perceived organisations, we calculated the entropy of each lattice for each subject. The model fit the data exceedingly well. The attraction constant did not vary much over subjects  相似文献   
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This series of studies investigated the ability of literate adults to exploit communications options that are available to writers but have no counterpart in speech. Specifically it examined people's use of sketches when giving written directions to help a stranger cross town. When writing an informal letter to a friend most directions were given in prose paragraph style (Experiment 1). Almost no-one included a sketch, even if given a street map as an aid. Yet most subjects could draw adequate sketch maps (Experiment 2), and everyone said yes when asked whether they would include a sketch in a letter. So the previous choices were not constrained either by graphic skill or by judgements concerning the appropriateness of a sketch, When people were asked to 'design' the back page of a leaflet they still did not include a sketch (Experiment 3). Experiment 4 showed that any bias in the instructions was towards rather than against the use of sketches. The need to generate the sketch was removed in Experiment 5 where subjects composed the leaflet page from pre-formed sections that included alternative routes in both words and diagrams. Nearly all subjects now included a sketch in their directions. In case subjects previously, in haste, had not considered the possibility of including a sketch map, they were made aware of the drawing option by rating the usability of route information in a variety of communication styles immediately before writing their own directions (Experiment 6). People rated directions that included diagrams as significantly more usable, but still most subjects did not include a sketch in the directions they gave. So the communication styles that readers recognized as successful were not determining their choices as writers. It is suggested that, when giving written directions, inexperienced writers rely too heavily on how they would respond as speakers.  相似文献   
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