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891.
Over repeated exposure to particular visual search displays, subjects are able to implicitly extract regularities that then make search more efficient-a phenomenon known as contextual cueing. Here we explore how the learning involved in contextual cueing is formed, maintained, and updated over experience. During an initial training phase, a group of signal first subjects searched through a series of predictive displays (where distractor locations were perfectly correlated with the target location), followed with no overt break by a series of unpredictive displays (where repeated contexts were uncorrelated with target locations). A second noise first group of subjects encountered the unpredictive displays followed by the predictive displays. Despite the fact that both groups had the same overall exposure to signal and noise, only the signal first group demonstrated subsequent contextual cueing. This primacy effect indicates that initial experience can result in hypotheses about regularities in displays-or the lack thereof-which then become resistant to updating. The absence of regularities in early stages of training even blocked observers from learning predictive regularities later on.  相似文献   
892.
893.
Although Directive 2001/20/EC of the European Parliament and of Council of 4 April 2001 on the approximation of the laws regulations and administrative provisions of the Member States relating to the implementation of good clinical practice in the conduct of clinical trials on medicinal products for human use does not contain an exception for emergency situations, and requires the informed consent of a legal representative in all cases where research is conducted on legally competent individuals who are unable to give informed consent, in Poland, emergency research can be conducted without consent. Polish regulations on emergency research can hardly be treated as a result of intentional legislative policy. Our provisions arise from multiple and sophisticated interpretations of different regulations that govern medical experiments on human subjects and clinical trials. These interpretations can be summarized as follows: (1) There are two categories of medical experiments: therapeutic and non-therapeutic experiments. Emergency research without consent may be conducted in the category of therapeutic experiment only (therapeutic experiment consists of the introduction by the physician of new or only partially proven diagnostic, therapeutic or preventive methods in order to achieve direct benefit to the health of the patients, and it can be carried out when hitherto applied methods were ineffective or their effectiveness was insufficient). (2). Emergency research may be conducted without consent if there is a situation of great urgency in which the research subject's life is in danger and there is no possibility of obtaining immediate consent from the research subject him or herself, or from his or her legal representative or guardianship court, and the research subject has not refused to give consent for the participation in an emergency therapeutic experiment. The legal representative or guardianship court shall be provided with all the relevant information concerning subject's participation in an experiment as soon as possible. All projects of emergency research with intent to be done without the research subject's consent must be approved by an independent bioethics committee. Because these five requirements seem to provide insufficient protection for a subject's autonomy and rights it is necessary to add to them two other conditions: (1) the emergency research could not be conducted using other research participants capable of giving informed consent; and (2) informed consent for continued participation in the emergency research shall be obtained from either the participant him or herself or the legally authorized representative as soon as possible (requirement of obtaining deferred consent). A consolidated single Act that will govern all aspects of medical experiments on human subjects, including emergency research, should be prepared and enacted as soon as possible.  相似文献   
894.
The anterior cingulate cortex (ACC) participates in evaluating actions and outcomes. Little is known on how action-reward values are processed in ACC and if the context in which actions are performed influences this processing. In the present article, we report ACC unit activity of monkeys performing two tasks. The first task tested whether the encoding of reward values is context dependent—that is, dependent on the size of the other rewards that are available in the current block of trials. The second task tested whether unexpected events signaling a change in reward are represented. We show that the context created by a block design (i.e., the context of possible alternative rewards) influences the encoding of reward values, even if no decision or choice is required. ACC activity encodes the relative and not absolute expected reward values. Moreover, cingulate activity signals and evaluates when reward expectations are violated by unexpected stimuli, indicating reward gains or losses.  相似文献   
895.
Recently academic freedom and academic tenure have been in the media spotlight because of concerns that academic freedom is being misused and that academic tenure provides job security to a select few. First, this paper provides a brief history of these two institutions and follow with an analysis using Stone’s (2002) policy analysis format. Second, this paper examines the university through two lenses: (a) an economic market lens; and (b) a community lens. These two lenses offer contrasting views of the university and help explain the different views of academic freedom and tenure. The authors suggest that faculty make use of the economic model to increase their chances of maintaining tenure in a university atmosphere frequently characterized by a business approach rather than a collegial one. Recommendations for future research are also provided.  相似文献   
896.
This study examined the effect of a self-esteem threat combined with exposure to thin images on body image (BI) satisfaction and investment. Female participants (N = 94) received a self-esteem threat consisting of false failure feedback or received false success feedback on an intellectual task allegedly highly predictive of academic and professional success. They then viewed media images featuring thin models or products. After viewing thin models, women who had received failure feedback declared themselves more satisfied about their appearance and less invested in it than did women who had received success feedback. These results suggest that exposure to the thin ideal may inspire women experiencing self-esteem threats to use appearance as an alternative source of worth, thus maintaining their global esteem through BI compensatory self-enhancement. Potential long-term implications of this strategy, such as a paradoxical increase in BI investment and the development of eating pathology, are discussed.  相似文献   
897.
OBJECTIVE: To investigate loss of control over eating in a sample of obese youngsters seeking treatment. METHOD: Obese youngsters (aged 10-16) were categorized into those having experienced loss of control (LC) and those who had not (NoLC) using the child version of the Eating Disorder Examination. Furthermore, the LC group was subdivided into an objective binge eating (OBE) and a subjective binge eating (SBE) group. The groups were compared on psychological measures. RESULTS: LC subjects (17.9%) showed more concern about eating, weight and shape. They also reported more emotional and external eating behaviors and more depression. Youngsters who report SBE show resemblances to both NoLC and OBE subjects. DISCUSSION: LC subjects are characterized by more eating-related psychopathology and higher levels of depression. Especially obese youngsters with OBE turned out to be a pathological group.  相似文献   
898.
This study examined the impact of applicant ethnicity, job type, and prejudice on evaluation biases and intentions to interview in an experimental simulation. We suggest that bias and discrimination are more likely when foreign applicants who belong to disliked ethnic groups apply for jobs that require high interpersonal skills, and when raters are prejudiced against immigrants. Subjects were Swiss university students who evaluated Swiss, Spanish, and Kosovo Albanian fictitious applicants. Foreign applicants were second‐generation immigrants, i.e., Swiss‐born descendants of immigrants. Thus, all applicants had similar schooling and language proficiencies but differed with respect to ethnicity. As predicted, discrimination was only observed for members of the disliked ethnic group (Kosovo Albanian) and not for members of the well‐accepted group (Spanish). Moreover, this discrimination was only apparent when applying for a job requiring high interpersonal skills and not when applying for a job requiring high technical skills. Symbolic prejudice towards second‐generation immigrants interacted with applicant ethnicity and job type to affect evaluations of foreign applicants: Persons high in symbolic prejudice devalued foreign applicants belonging to the disliked group but only when applying for a job requiring high interpersonal skills. Overt prejudice was unrelated to evaluations and intentions to interview. These results suggest that discrimination against immigrants is highly specific, targeting only members of certain ethnic groups who apply for certain types of jobs. Moreover, evaluation biases may be more apparent in raters who are prejudiced. Thus, our results support the notion that discrimination for employment results from a complex interaction between characteristics of the applicant, the job, and the rater.  相似文献   
899.
900.
The lack of programs to train people in practical problem-solving is one of the challenges that professionals who attend people with mental deficiency must cope with. The main goal of this study is to assess the effects of a program designed to improve these skills, aimed at people with intellectual discapacity. The sample was made up of 66 subjects, aged between 17 and 36 years old. The program was based on the use of examples of fictitious characters who undergo situations that are similar to those of the subjects to whom the program is administered, and techniques to improve skills were generated from these situations. In order to achieve the goal, a classic pre- posttest design was used, with an experimental and a control group. The results show positive effects in most of the variables considered as a consequence of the administration of the program.  相似文献   
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