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51.
Little is known about how a prey species' cognitive limitations might shape a predator's prey-capture strategy. A specific hypothesis is investigated: predators take advantage of times when the prey's attention is focussed on its own prey. Portia fimbriata, an araneophagic jumping spider (Salticidae) from Queensland, is shown in a series of 11 experiments to exploit opportunistically a situation in which a web-building spider on which it preys, Zosis genicularis (Uloboridae), is preoccupied with wrapping up its own prey. Experimental evidence supports three conclusions: (1) while relying on optical cues alone, P. fimbriata perceives when Z. genicularis is wrapping up prey; (2) when busy wrapping up prey, the responsiveness of Z. genicularis to cues from potential predators is diminished; and (3) P. fimbriata moves primarily during intervals when Z. genicularis is busy wrapping up prey. P. fimbriata's strategy is effective partly because the wrapping behaviour of Z. genicularis masks the web signals generated by the advancing P. fimbriata's footsteps and also because, while wrapping, Z. genicularis' attention is diverted away from predator-revealing cues. Electronic Publication  相似文献   
52.
While obsessive–compulsive disorder is widely recognized to have a strong genetic component, psychosocial factors are also acknowledged to be important. The primary focus of this paper is on familial factors associated with OCD in children and adolescents. It explores the family context as a possible risk factor in the development and maintenance of the disorder, including parental modeling, expressed emotion, parenting style, and family accommodation of the child's symptoms. The involvement of the family in the treatment of the disorder is also reviewed. Finally, future directions for research investigating familial factors in childhood OCD are presented.  相似文献   
53.
Relations between adult anxiety and mood disorders and retrospective reports of excessive childhood shyness were investigated in the US National Comorbidity, Survey (n=5877). Results indicated that 26% of women and 19% of men described themselves as 'very shy' when they were growing up. Of these shy individuals, 53% of women and 40% of men met criteria for a lifetime diagnosis of one or more anxiety or mood disorders. Relations between excessive shyness and each of the anxiety and mood disorders were examined after adjusting for elevated neuroticism, self-criticism, and low maternal care. The largest odds ratios were found for social phobia in both men and women, particularly for the complex subtype of this disorder. Significant associations also emerged for posttraumatic stress disorder in women and for major depressive disorder in men. Childhood shyness remained significantly associated with a lifetime history of social phobia when individuals with current (past year) social phobia were excluded from the analysis. The results of this study suggest that childhood shyness is strongly related to the complex subtype of social phobia in the general population. Excessive shyness does not appear to be strongly associated with other anxiety and mood disorders when related psychosocial and developmental dimensions are statistically controlled. Finally, many individuals who report excessive childhood shyness do not meet criteria for any anxiety or mood disorder. In a similar fashion, approximately 50% of individuals with a lifetime history of complex social phobia did not view themselves as very shy when growing up.  相似文献   
54.
This research examined the concept of power in Japan, France, Germany, and the United States, as well as beliefs about the emotions persons in power tend to elicit in others and about powerful people's regulation (specifically, inhibition) of certain emotions. Definitions of power were assessed by examining the importance of two main components: control over self versus other and freedom of action vis-à-vis social norms. Beliefs about both positive (pride, admiration) and negative (jealousy, contempt) emotions were measured. Analyses revealed that the concept of power differed across countries and that the definitions of power as well as country of origin significantly predicted beliefs about the emotions that are elicited in others by powerful people and also the regulation of expression of emotion by powerful people.  相似文献   
55.
The aim of this study was to examine differences in responses to the Caregiver Strain Questionnaire (CGSQ) between African American and White caregivers of children with emotional and behavioral challenges. Significant item- and scale-level differences were detected across groups with African Americans consistently reporting less strain. We examined whether these differences were more likely due to nonequivalent measurement than to real differences in the experience of caregiver strain. Confirmatory factor analysis showed that the model fit the data well for both racial groups, but there were some differences in structural components. Internal consistency was equivalent across the groups. In an examination of criterion validity, regression analyses showed that African American caregivers experienced a slower rate of increase in objective caregiver strain at a given increase in child internalizing problems. No other race differences were found in the regression analyses. In general, we conclude that the CGSQ can be useful for detecting caregiver strain and identifying family support needs for both White and African American caregivers. Differences across groups in reports of caregiver strain, however, call for more research on racial differences in the impact on the family of caring for a child with emotional and behavioral disorders.  相似文献   
56.
Four principal arguments have been offered in support of requiring public and private third-party payers to help fund medical research: (1) many of the costs associated with clinical trial participation are for routine care that would be reimbursed if delivered outside of a trial; (2) there is a need to promote scientific research and medical progress and lack of coverage is an impediment to enrollment; (3) to cover the costs of trials expands health care and treatment options for the sick; and (4) it is beneficial for private insurers to cover the costs associated with cancer clinical trials because doing so makes such companies more attractive to consumers. Although many see third-party-payer coverage as a victory for patients and for the future of research, requiring coverage of services provided in a trial beyond those that would be provided to a comparable patient outside the research context raises a number of concerns.  相似文献   
57.
The extent to which the Comprehensive System for the Rorschach is reliably scored has been a topic of some controversy. Although several studies have concluded it can be scored reliably in research settings, little is known about its reliability in field settings. This study evaluated the reliability of both response-level codes and protocol-level scores among 84 adolescent psychiatric inpatients in a clinical setting. Rorschachs were originally administered and scored for clinical purposes. Among response codes, 87% demonstrated acceptable reliability(> .60), and most coefficients exceeded .80. Results were similar for protocol-level scores, with only one score demonstrating less than adequate reliability. The findings are consistent with previous evidence, indicating reliable scoring is possible even in field settings.  相似文献   
58.
The World Wide Web (WWW) poses a distinct capability to offer interventions tailored to the individual's characteristics. To fine tune the tailoring process, studies are needed to explore how Internet accessibility and usage are related to demographic, psychosocial, behavioral, and other health related characteristics. This study was based on a cross-sectional survey conducted on 2373 7th grade students of various ethnic groups in Southern California. Measures of Internet use included Internet use at school or at home, Email use, chat-room use, and Internet favoring. Logistic regressions were conducted to assess the associations between Internet uses with selected demographic, psychosocial, behavioral variables and self-reported health statuses. The proportion of students who could access the Internet at school or home was 90% and 40%, separately. Nearly all (99%) of the respondents could access the Internet either at school or at home. Higher SES and Asian ethnicity were associated with higher internet use. Among those who could access the Internet and after adjusting for the selected demographic and psychosocial variables, depression was positively related with chat-room use and using the Internet longer than 1 hour per day at home, and hostility was positively related with Internet favoring (All ORs = 1.2 for +1 STD, p < 0.05). Less parental monitoring and more unsupervised time were positively related to email use, chat-room use, and at home Internet use (ORs for +1 STD ranged from 1.2 to 2.0, all p < 0.05), but not related to at school Internet use. Substance use was positively related to email use, chat-room use, and at home Internet use (OR for "used" vs. "not used" ranged from 1.2 to 4.0, p < 0.05). Self-reported health problems were associated with higher levels of Internet use at home but lower levels of Internet use at school. More physical activity was related to more email use (OR = 1.3 for +1 STD), chat room use (OR = 1.2 for +1 STD), and at school ever Internet use (OR = 1.2 for +1 STD, all p < 0.05). Body mass index was not related to any of the Internet use-related measures. In this ethnically diverse sample of Southern California 7(th) grade students, 99% could access the Internet at school and/or at home. This suggests that the Internet is already a potential venue for large scale health communication studies. Adolescents with more psychosocial risk factors or detrimental health behaviors were more likely to use the Internet. Therefore, if used properly, Internet interventions could effectively address the high risk populations. Additional research is needed to gain a more complete understanding of the positive and negative consequences of Internet use among adolescents.  相似文献   
59.
The transmission of tool use is a rare event in monkeys. Such an event arose in a group of semi-free-ranging Tonkean macaques (Macaca tonkeana) in which leaning a pole against the parks fence (branch leaning) appeared and spread to several males. This prompted us to test individual and social learning of this behavior in seven young males. In the first experiment, three males learned individually to obtain a food reward using a wooden pole as a climbing tool. They began using the pole to retrieve the reward only when they could alternatively experience acting on the object and reaching the target. In a second experiment, we first tested whether four other subjects could learn branch leaning after having observed a group-mate performing the task. Despite repeated opportunities to observe the demonstrator, they did not learn to use the pole as a tool. Hence we exposed the latter subjects to individual learning trials and they succeeded in the task. Tool use was not transmitted in the experimental situation, which contrasts with observations in the park. We can conclude that the subjects were not able to recognize the target as such. It is possible that they recognized it and learned the task individually when we alternated the opportunity to act upon the object and to reach the reward. This suggests that these macaques could then have associated the action they exercised upon the pole and the use of the pole as a means to reach the reward.  相似文献   
60.
Seven different laboratory measures of impulsivity were administered to a group of 165 school-aged boys. Parents' and teachers' ratings of Attention Deficit and Hyperactivity Disorder and Oppositional/Defiant Disorder were also obtained. Factor analyses of impulsivity measures revealed the existence of a strong Inhibitory Control Factor including measures derived from Stop Task, the Continuous Performance Test, the Matching Familiar Figures Test, and the Circle Tracing Task. Other forms of impulsivity like resistance to interference, the Wisconsin Card Sorting Test and efficiency in the DRL Task loaded on a second independent factor. The Inhibitory Control factor was correlated with ADHD ratings, whereas the second factor was slightly related to the presence of ODD symptoms. Discussion is focused on the relevance of inhibitory control in impulsivity and ADHD research.  相似文献   
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