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31.
Abstract - Family characteristics influence children's behavioral development, but so do variations in schools, neighborhoods, and communities. We documented extrafamilial environmental effects by fitting maximum likelihood models to questionnaire data collected from double dyads consisting of twins and their classmate controls. The classmate controls in each double dyad were genetic strangers living in separate households, but they shared school, neighborhood, and community environments with their yoked twin pair and with one another. At ages 11 to 12, the control classmates showed significant similarities in religious practices and smoking and drinking patterns, demonstrating that environmental influences outside the family affect children's behavioral development. Familial self-selection of residential neighborhoods may have contributed to these results, but direct effects of variation across communities, neighborhoods, and schools cannot be dismissed, and such effects warrant further study. 相似文献
32.
Lea DH 《Journal of genetic counseling》1999,8(3):175-181
Genetic counseling and the many roles a genetic counselor must assume to provide quality genetic health care are becoming increasingly complex, especially when the genetic condition is rare, and DNA testing is costly and not yet routinely used. A case study of a couple with a family history of retinoblastoma and their pursuit of DNA testing for prenatal diagnosis is presented. The case study illustrates the instrumental role of the genetic counselor in advocating for clients for genetic services such as DNA testing and in educating insurance companies in the nature and importance of such services to achieve improved client health care outcomes. 相似文献
33.
象思维是中华民族的传统思维.深深影响着中国文化.<周易>蕴含着丰富的象思维,可以分为观物取象、立象尽意、得意忘象三个层面.中国画作为中华传统文化的典型代表,深受中国哲学的影响.石涛是清初著名画家,以擅长山水画闻名于世.他的画论<苦瓜和尚画语录>和其题画诗清晰地展现了其山水画深受<周易>象思维的影响,认为"画者形天地万物"、"画者从于心者也"、"不似似之当下拜".石涛山水画创作的这个过程与<周易>象思维的三个层面是一致的. 相似文献
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Edmund J. S. Sonuga-Barke Stephen E. G. Lea Paul Webley 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1989,41(2):161-179
Three experiments examined the effects of economic constraint (time restriction—trials restriction) on adult humans' performance on concurrent chained schedules of reinforcement in which terminal links differed both in reward size and pre-reward delay levels. In the first, terminal links offered a long delay (20, 30, 40, 50 sec) followed by 2 points, or a short delay (10 sec) followed by 1 point. Initial links consisted of the same variable interval schedules for each alternative. Subjects showed a conditional sensitivity to increases in delay. Under a time constraint, there was an increasing preference for the smaller reward as the delay to the larger reward was increased, whereas under a trials constraint subjects were totally insensitive to such changes. In the second experiment, this finding was replicated using long and short periods of video game playing as large and small rewards. In the third experiment terminal link parameters remained constant (2 points after 15 sec, or 1 point immediately), but initial link parameters were manipulated (either VI 1-sec, 8-sec, or 20-sec) so that the higher relative rate of reward shifted from being associated with the small reward to being associated with the large reward. Again subjects chose differently under the two constraints. Subjects under the time constraint exhibited a preference for the small reward at all levels of initial link, but under the trials constraint subjects preferred the large reward. Subjects in the time constraint condition thus exhibited a maladaptive insensitivity to changes in the initial link duration. These findings are interpreted as supporting a miscalculation rather than a discounting interpretation of human performance on “self-control” tasks. 相似文献
36.
Stephen E.G. Lea Annette Lohmann Catriona M.E. Ryan 《The Quarterly Journal of Experimental Psychology Section B: Comparative and Physiological Psychology》1993,46(1):19-42
Pigeons were trained to discriminate between stimuli constructed using five orthogonal two-valued features. The stimuli consisted of stylized monochrome drawings of seeds. Two different training procedures (conditional and simultaneous discrimination) were used. In the first two experiments, the discrimination required was between polymorphous categories, in which a positive stimulus was defined as one in which three or more of the five features took their positive values. Discrimination in both experiments was imperfect; the pigeons' behaviour only came under the control of a subset of the available features (one to three in Experiment 1, three or four in Experiment 2). In Experiment 3, single features had to be discriminated, while the remaining features varied. It was found that all five features of the “seed” stimuli could be discriminated, but one of them was exceptionally difficult. The results show that pigeons do not reliably use all the features available to them when making category discriminations. This casts doubts on feature analysis as a basis for the excellent performance pigeons show when required to discriminate between categories of natural objects. 相似文献
37.
Behavioural flexibility allows animals to adjust their behaviours according to changing environmental demands. Such flexibility is frequently assessed by the discrimination–reversal learning task. We examined grey squirrels’ behavioural flexibility, using a simultaneous colour discrimination–reversal learning task on a touch screen. Squirrels were trained to select their non-preferred colour in the discrimination phase, and their preferred colour was rewarded in a subsequent reversal phase. We used error rates to divide learning in each phase into three stages (perseveration, chance level and ‘learned’) and examined response inhibition and head-switching during each stage. We found consistent behavioural patterns were associated with each learning stage: in the perseveration stage, at the beginning of each training phase, squirrels showed comparable response latencies to correct and incorrect stimuli, along with a low level of head-switching. They quickly overcame perseveration, typically in one to three training blocks. In the chance-level stage, response latencies to both stimuli were low, but during initial discrimination squirrels showed more head-switches than in the previous stage. This suggests that squirrels were learning the current reward contingency by responding rapidly to a stimulus, but with increased attention to both stimuli. In the learned stage, response latencies to the correct stimulus and the number of head-switches were at their highest, whereas incorrect response latencies were at their lowest, and differed significantly from correct response latencies. These results suggest increased response inhibition and attention allowed the squirrels to minimise errors. They also suggest that errors in the ‘learned’ stage were related to impulsive emission of the pre-potent or previously learned responses. 相似文献
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Jessica E. Rohlfing Laura Nota Lea Ferrari Salvatore Soresi Terence J.G. Tracey 《Journal of Vocational Behavior》2012,81(3):330-337
The relations of differential occupational knowledge with interests and competence perceptions in children as well as how these relations were moderated by gender and grade were examined in this study using an Italian sample. Data were collected from samples of elementary school and middle school children (N = 539). The Inventory of Children's Activities—Revised (ICA-R; Tracey & Ward, 1998) was used to assess children's interest and competency perceptions in various activities associated with the Holland's RIASEC types. The Occupational Knowledge Scale (OKS) was created for this study, and consisted of a representative sampling of occupational titles to which children indicated their knowledge. Hierarchical regression results indicated a relationship between knowledge, interests, and competence perceptions in children. With regard to overall knowledge, no relationship was found between general knowledge and either grade or gender. More specific examination of the type of knowledge as it varied across the dimensions of People–Things, and Data–Ideas demonstrated that there appeared to be a specific pattern relating interest, gender, and grade to knowledge of occupations. For knowledge of people relative to things occupations, higher interest, higher grade level, and being female predicts stronger knowledge of people occupations. It was also found that interest in ideas predicts stronger knowledge of ideas occupations, and being male predicts stronger knowledge of high prestige occupations. Generally, competence perceptions did not have a unique relation with one's knowledge of People–Things, Ideas–Data, or Prestige; however, girls who reported higher competence had greater knowledge of ideas occupations. 相似文献