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991.
A particularly important aspect of executive functioning involves the ability to form and carry out complex plans, that is to say planning. This study aimed to investigate planning in 18 older and 16 younger normal participants using an ecological planning subtask derived from the Behavioural Assessment of the Dysexecutive Syndrome test battery, the "Zoo Map Test." There are two trials. The first trial consists of a "high demand" version of the subtask in which the participants must plan in advance the order in which they will visit designated locations in a zoo (formulation level). In the second, or "low demand" version, the participant is simply required to follow a concrete externally imposed strategy to reach the locations to visit (execution level). The two-way ANOVAs mainly showed more difficulties in elderly adults than in younger adults, more difficulties in formulation level than in execution level, and lastly a greater difference between formulation and execution in older participants than in younger adults. These results suggest that elderly participants have some problems developing logical strategies whereas they are able to execute complex predetermined plans.  相似文献   
992.
In this study we examined self-reported suicide attempts and their relationship to other health risk factors in a community sample of 16,644 adolescents. Fifteen percent endorsed suicide attempts (10% single; 5% multiple attempts) We hypothesized that multiple attempters would show higher prevalence of comorbid health risks than single or non-attempters. The three groups showed significant differences in ten health risk domains, on factors such as depressed mood, sexual assault, weight problems, and drug and alcohol use (ORs: 3.26-13.57). Repeated suicide attempts appear to be related to increased vulnerability and likelihood of harm in multiple domains of health risk.  相似文献   
993.
The present study explored how European American women in midlife transition think about their changing bodies and related sociocultural discourses. The work was informed by theory that illuminates a process in which middle-aged individuals critically evaluate the meaning structures used to make sense of the world and self and transform these schemes for personal relevance. In-depth interviews were conducted with 20 women transitioning into their middle-aged years. Data were analyzed using constant comparison processes. Analyses revealed two major ideological adjustments in participants' thinking, including (a) the shift from an emphasis upon external to internal aspects of the self and (b) the questioning of dominant social discourses about the female body. Although these ideological shifts seemingly contributed to participants' acceptance of their bodies at midlife, participants also expressed ambivalence about their appearances and related social discourses.  相似文献   
994.
This article focuses on two possible missions for a national bioethics commission. The first is handling differences of worldview, political orientation, and discipline. Recent work in political philosophy emphasizes regard for the dignity of difference manifested in "conversation" that seeks understanding rather than agreement. The President's Council on Bioethics gets a mixed review in this area. The second is experimenting with prophetic bioethics. "Prophetic bioethics" is a term coined by Daniel Callahan to describe an alternative to compromise-seeking "regulatory bioethics." It involves a critique of modern medicine. In the contemporary context, the areas of biotechnology and access to health care cry out for prophetic attention. The Council has addressed biotechnology; unfortunately, that experience suggests that the kind of prophecy that it practices poses risks to conversation. With regard to access issues, the article proposes an effort that unites themes of human dignity, solidarity, and limits in support of reform, while highlighting, rather than papering over, differences.  相似文献   
995.
996.
This study compared investigator ratings of ADHD symptoms based on interviews with parents and teachers during a doubleblind, placebo-controlled study of atomoxetine. Investigators completed the ADHD Rating Scale: Investigator (ADHDRS-I) based on separate semistructured interviews with the primary caretaker and teacher of the participant. Interviews were conducted at Visits 2 to 7 during a double-blind treatment protocol comparing atomoxetine (N= 10) and placebo (N= 6). Both parent and teacher-based ratings were sensitive to change in ADHD symptoms with atomoxetine treatment. Parent-based assessment differentiated significantly between treatment with atomoxetine and placebo, whereas teacher-based assessment was less sensitive to change. Parents and teachers showed good agreement on change in ADHDRS-I scores. Investigator ratings based on parent- and teacher-report were sensitive to change in symptoms of ADHD during treatment with atomoxetine. Despite good agreement between parent- and teacher-based ratings of symptom change, parent-based ADHD symptom ratings are more sensitive to symptom change.  相似文献   
997.
Temporal ventriloquism: sound modulates the flash-lag effect   总被引:3,自引:0,他引:3  
A sound presented in close temporal proximity to a visual stimulus can alter the perceived temporal dimensions of the visual stimulus (temporal ventriloquism). In this article, the authors demonstrate temporal ventriloquism in the flash-lag effect (FLE), a visual illusion in which a flash appears to lag relative to a moving object. In Experiment 1, the magnitude and the variability of the FLE were reduced, relative to a silent condition, when a noise burst was synchronized with the flash. In Experiment 2, the sound was presented before, at, or after the flash (+/- approximately 100 ms), and the size of the FLE varied linearly with the delay of the sound. These findings demonstrate that an isolated sound can sharpen the temporal boundaries of a flash and attract its temporal occurrence.  相似文献   
998.
Four chimpanzees were highly accurate in selecting the larger of two concurrent accumulations of bananas in two opaque containers over a span of 20 min. One at a time, bananas were placed into the containers, which were outside the chimpanzees' cages. The chimpanzees never saw more than one banana at a time, and there were no cues indicating the locations of the bananas after they were placed into the containers. The performance of these animals matched that of human infants and young children in similar tests. The chimpanzees were successful even when the sets to be compared were sufficiently large (5 vs. 8, 5 vs. 10, and 6 vs. 10) to cast doubt on the possibility that the chimpanzees were using an object file mechanism. These chimpanzees are the first nonhuman animals to demonstrate extended memory for accumulated quantity.  相似文献   
999.
In a previous study, search for a notched-disk target abutting a square among complete-disk nontargets and squares was inefficient in 250-ms exposures, but relatively efficient in 100-ms exposures. This finding was interpreted as evidence that amodal completion proceeds through a mosaic and then a completion stage, with the latter preempting the former. We used the same target but changed its context: Nontargets were instead notched disks near squares. Task set was also different: Participants searched for a complete disk. Contrary to the prediction of the preemption model, search was efficient in the 100-ms condition and inefficient in the 250-ms condition. We propose that in both the present and the previous studies, the target was ambiguous, and task set and context affected how it was perceived. In both experiments, set effects were evident for 100-ms exposures; context effects were evident for 250-ms exposures.  相似文献   
1000.
Images of faces manipulated to make their shapes closer to the average are perceived as more attractive. The influences of symmetry and averageness are often confounded in studies based on full-face views of faces. Two experiments are reported that compared the effect of manipulating the averageness of female faces in profile and full-face views. Use of a profile view allows a face to be ”morphed“ toward an average shape without creating an image that becomes more symmetrical. Faces morphed toward the average were perceived as more attractive in both views, but the effect was significantly stronger for full-face views. Both full-face and profile views morphed away from the average shape were perceived as less attractive. It is concluded that the effect of averageness is independent of any effect of symmetry on the perceived attractiveness of female faces.  相似文献   
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