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701.
In the present study, the authors examined somatosensory processing in 30 biological relatives of persons with schizophrenia (hereafter called "schizophrenia relatives"), 30 biological relatives of persons with bipolar affective disorder (psychiatric family control subjects), and 30 healthy control subjects with no family history of psychopathology. All 3 groups completed a weight discrimination task, a 2-point discrimination task, and a complex cognitive somatosensory task (i.e., graphesthesia). The schizophrenia relatives performed significantly worse on all 3 somatosensory tasks compared with both the healthy control subjects and the bipolar relatives. The healthy control subjects and psychiatric family control subjects showed no significant differences on any of the somatosensory tasks. Within the weight discrimination and 2-point discrimination tasks, schizophrenia relatives showed group differences on the d' index, the measure of sensitivity, whereas all 3 groups did not differ on lnbeta, the measure of response bias, suggesting a genuine difference in weight and touch sensitivity. The d' value of the weight discrimination task was significantly associated with both the cognitive-perceptual factor and negative symptom factor of the clinical questionnaire (e.g., Schizotypal Personality Questionnaire; SPQ), whereas the 2-point discrimination d' value and graphesthesia scores were significantly associated only with the cognitive-perceptual factor of the SPQ. Implications for the possible relation between somatosensory task performance and schizophrenia liability are discussed.  相似文献   
702.
We administered the Tower of Hanoi to demographically comparable samples of control participants (n = 34) and children with the Combined (n = 22) and Inattentive subtypes (n = 19) of Attention-Deficit/Hyperactivity Disorder (ADHD). Controls excelled over children with the Inattentive subtype, who outperformed patients with the Combined subtype. These results replicated findings of greater executive deficits in the Combined than in the Inattentive type of ADHD. Double-blind administration of methylphenidate improved task performance only for patients with the Inattentive subtype. In a drug-free Baseline session, children with both subtypes of ADHD made more private verbalizations than controls, particularly when failing puzzles. In later sessions, regardless of drug condition, the inattentive sample exhibited a smaller increase in self-regulatory utterances under failure. In contrast, the combined sample decreased self-regulatory verbalizations under failure only under methylphenidate. The results support some differences between the two subtypes of ADHD in executive functioning and in their response to stimulant therapy. Portions of these results were submitted as part of H. Theresa Chang's PhD dissertation (Chang, 2000) and Helena Kopecky's unpublished master's research, both conducted at the University of Rochester and supervised by Rafael Klorman.  相似文献   
703.
Liu CH  Chaudhuri A 《Cognition》2002,83(1):31-48
It is generally accepted that unfamiliar faces are better recognized if presented in 3/4 view. A common interpretation of this result is that the 3/4 view represents a canonical view for faces. This article presents a critical review of this claim. Two kinds of advantage, in which a 3/4 view either generalizes better to a different view or produces better recognition in the same view, are discussed. Our analysis of the literature shows that the first effect almost invariably depended on different amounts of angular rotation that was present between learning and test views. The advantage usually vanished when angular rotation was equalized between conditions. Reports in favor of the second effect are scant and can be countered by studies reporting negative findings. To clarify this ambiguity, we conducted a recognition experiment. Subjects were trained and tested on the same three views (full-face, 3/4 and profile). The results showed no difference between the three view conditions. Our analysis of the literature, along with the new results, shows that the evidence for a 3/4 view advantage in both categories is weak at best. We suggest that a better predictor of performance for recognition in different views is the angular difference between learning and test views. For recognition in the same view, there may be a wide range of views whose effectiveness is comparable to the 3/4 view.  相似文献   
704.
学校危险和保护因素与初中生偏差行为的关系   总被引:9,自引:0,他引:9       下载免费PDF全文
学校危险因素和保护因素对初中生的偏差行为有重要影响.本研究以1739名初中学生为被试,考察了学校危险因素和保护因素及其与青少年偏差行为的关系.结果表明:(1)学校危险因素和保护因素分别与初中生偏差行为有显著的正相关和负相关;(2)学校危险因素得分随年级升高而增长,保护因素得分随年级升高而降低;(3)“偏差行为榜样”、“教师的支持”、“知觉到积极期望”是对初中生偏差行为有重要影响的三个学校环境因素.  相似文献   
705.
Many factors influence the development of body image, one of which is the perception we have of our body. Perception can refer to actual visual input or the interpretation of vision; in other words, cognitive appraisal. The goal of this preliminary study is to determine if three groups (body dysmorphic disorder, obsessive-compulsive disorder, and a non-psychiatric control group) differed in the perception of their faces. Thirty individuals, 10 in each group, were asked to make changes to a computerized image of their face. In addition, affective and perceptual tests were administered. The groups did not differ on affective and perceptual organizational measures, although the obsessive-compulsive disorder group reported a higher level of anxiety than the body dysmorphic disorder group. Imaging software showed that facial features were modified by patients with body dysmorphic disorder and obsessive-compulsive disorder in about 50% of cases. No modifications were made in the control group. Future studies need to investigate the possible causes of these differences.  相似文献   
706.
This study attempted to address limitations in the understanding of optimism and pessimism among middle-aged adults. Specifically, a model of affectivity as a mediator of the link between outcome expectancies and psychological adjustment (life satisfaction and depressive symptoms) was presented and examined in a sample of 237 middle-aged adults. Consistent with a mediation model, results of path analyses indicated that optimism and pessimism (particularly the former) had significant direct and indirect links (by means of positive and negative affectivity) with depressive symptoms and life satisfaction. These results add to the small but growing literature identifying optimism and pessimism as important concomitants of psychological adjustment in more mature adults.  相似文献   
707.
In the marine mollusk Aplysia, the CCAAT/enhancer-binding protein, ApC/EBP, serves as an immediate early gene in the consolidation of long-term facilitation in the synaptic connection between the sensory and motor neurons of the gill-withdrawal reflex. To further examine the role of ApC/EBP as a molecular switch of a stable form of long-term memory, we cloned the full-length coding regions of two alternatively spliced forms, the short and long form of ApC/EBP. Overexpression of each isoform by DNA microinjection resulted in a l6-fold increase in the expression of the coinjected luciferase reporter gene driven by an ERE promoter. In addition, when we overexpressed ApC/EBP in Aplysia sensory neurons, we found that the application of a single pulse of 5-HT that normally induced only short-term facilitation now induced long-term facilitation. Conversely, when we attempted to block the synthesis of native ApC/EBP by microinjecting double-strand RNA or antisense RNA, we blocked long-term facilitation in a sequence-specific manner. These data support the idea that ApC/EBP is both necessary and sufficient to consolidate short-term memory into long-term memory. Furthermore, our results suggest that this double-strand RNA interference provides a powerful tool in the study of the genes functioning in learning and memory in Aplysia by specifically inhibiting both the constitutive and induced expression of the genes.  相似文献   
708.
Community-based participatory research (CBPR) is increasingly being used to better understand and improve the health of diverse communities. A key strength of this research orientation is its adaptability to community contexts and characteristics. To date, however, few studies explicitly discuss adaptations made to CBPR principles and processes in response to community context and partners’ needs. Using data from our CBPR study, the San Francisco Chinatown Restaurant Worker Health and Safety Project, and drawing from literature on immigrant political incorporation, we examine the links between the contexts of the Chinese immigrant worker community, adaptations made by our collaborative, and study outcomes. In particular, we explore the concepts of contexts of reception and participatory starting points, which may be especially relevant for partnerships with immigrant communities whose members have historically had lower rates of civic and political participation in the US. We discuss contextual findings such as worker partner accounts of language barriers, economic and social marginalization, and civic skills and participation, as well as subsequent adaptations made by the partnership. We also describe the relative effectiveness of these adaptations in yielding equitable participation and building partners’ capacity. We conclude by sharing lessons learned and their implications for CBPR and partnerships with immigrant communities more broadly.  相似文献   
709.
It is usually difficult to undercool Ti–Al alloys on account of their high reactivity in the liquid state. This results in a serious scarcity of information on their thermophysical properties in the metastable state. Here, we report on the surface tension of a liquid Ti–Al alloy under high undercooling condition. By using the electromagnetic levitation technique, a maximum undercooling of 324 K (0.19 T L) was achieved for liquid Ti-51 at.% Al alloy. The surface tension of this alloy, which was determined over a broad temperature range 1429–2040 K, increases linearly with the enhancement of undercooling. The experimental value of the surface tension at the liquidus temperature of 1753 K is 1.094 N m?1 and its temperature coefficient is ?1.422 × 10?4 N m?1 K?1. The viscosity, solute diffusion coefficient and Marangoni number of this liquid Ti–Al alloy are also derived from the measured surface tension.  相似文献   
710.
Abstract

Since the early 1990s the Singapore government has been taking a more liberal stance on controversial issues such as gay rights, embryonic stem cell research and the gaming industry. My paper analyses the Singapore state's utilitarian justification and its authoritarian enactment of these liberal policies. The first part looks at the underlying motivation for the cultural makeover. I frame my analysis around the reaction of the Singapore Christian community to these developments. I focus on the criticisms of the state's ‘liberal’ agenda made by Evangelicals, and describe how the People's Action Party (PAP) regime has defended these policies on utilitarian grounds. The first part ends with a comparative analysis of how the ‘cultural war’ debate was played out in Singapore and the USA. In the second part I examine the procedural aspects of this cultural experimentation. I start with a review of Singapore's political reform. I show that civil society in Singapore has attained a new openness. Yet there remain constraints, leading critics to label the PAP-led government as a ‘soft-authoritarian’ democracy. Singapore's cultural policies, I explain, are essentially an ‘elitist’ state-engineered top-down development. This is in contrast to the experience in the USA, where grassroots activists exercise tangible bottom-up influence on how cultural contests are resolved. My main thesis is to argue that Singapore's recent cultural liberalisation is guided by social–economic expediency notwithstanding the alleged moral risks, and that these are state-commanded liberal experimentations, imposed by the ruling elite upon a constituency that is still largely conservative in moral outlook.  相似文献   
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