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201.
The reliability and validity of the Parent's Observations of Social Interactions (POSI), a new, seven‐item screening instrument for autism spectrum disorders (ASD), is examined in two substudies. In Study 1, parents of 217 children (18–48 months) evaluated at a developmental clinic completed intake questionnaires that included the POSI and the Modified Checklist for Autism in Toddlers (M‐CHAT) checklist. POSI and M‐CHAT scores were compared to clinical evaluation results to assess reliability and validity. In Study 2, parents of 232 children (16–36 months) from both primary care and subspecialty settings completed the POSI, the M‐CHAT, and a report of their child's diagnoses. POSI and M‐CHAT scores were compared to reported diagnoses to assess reliability and validity. In both studies, the POSI demonstrated adequate internal reliability (Cronbach α = 0.83 and 0.86, respectively). In Study 1, POSI sensitivity (89%) was higher than that for the M‐CHAT (71%; p < .05); specificities were not significantly different (POSI: 54%, M‐CHAT: 62%). In Study 2, sensitivity (83%) compared favorably to that for the M‐CHAT (50%), although specificity was lower (75 vs. 84%). Despite its brevity, the POSI demonstrated good internal reliability and comparable sensitivity/specificity to the M‐CHAT checklist in two independent populations. If results are reproduced in larger, more diverse samples, the POSI may provide an efficient method for ASD screening in young children.  相似文献   
202.
Bayesian rationality is the paradigm of rational behavior in neoclassical economics. An economic agent is deemed rational when she maximizes her subjective expected utility and consistently revises her beliefs according to Bayes's rule. The paper raises the question of how, when and why this characterization of rationality came to be endorsed by mainstream economists. Though no definitive answer is provided, it is argued that the question is of great historiographic importance. The story begins with Abraham Wald's behaviorist approach to statistics and culminates with Leonard J. Savage's elaboration of subjective expected utility theory in his 1954 classic The Foundations of Statistics. The latter's acknowledged fiasco to achieve a reinterpretation of traditional inference techniques along subjectivist and behaviorist lines raises the puzzle of how a failed project in statistics could turn into such a big success in economics. Possible answers call into play the emphasis on consistency requirements in neoclassical theory and the impact of the postwar transformation of U.S. business schools.  相似文献   
203.
204.
In this I essay I analyse four sermons delivered at Shan festivals that celebrates the end of the Rains Retreat (Waa). I first argue that sermons in general are important sources of information about lived Buddhism. I next provide background information necessary to understand the sermon events and the sermons. In conclusion, I compare the sermons and discuss what laypeople can learn from sermons and what we, as academics, can learn from them.  相似文献   
205.
Background. Problem behaviour is common following pre‐term birth, but the underlying nature of these difficulties is not well known. Aims. We sought to establish the mechanisms underpinning behavioural difficulties in very pre‐term (VPT) children in middle childhood by comparing their performance to that of term born peers on tasks of working memory, inhibition, and processing speed, and relating these to parent and teacher assessments of their behaviour. Particular focus was given to inattention and overactive/impulsive behaviour, as these behaviours have been associated with different neuropsychological problems in term children. Samples. A group of VPT children (gestational age < 31 weeks, N= 56) aged 9–10 years and term controls (N= 22) participated in the study. Method. Children were assessed with measures of working memory, inhibition, and processing speed. Parents and teachers reported behavioural problems using the Strengths and Difficulties Questionnaire and two additional scales measuring overactive/impulsive behaviour and inattention. Results. Results revealed increased rates of problem behaviour in VPT compared to term children for parent‐rated total difficulties, hyperactivity, emotional problems, peer problems, prosocial behaviour, overactive/impulsive behaviour, and parent‐ and teacher‐rated inattention. Processing speed and working memory, but not inhibition, were significantly related to inattentive and overactive/impulsive behaviour. Conclusions. The increased rates of inattention and overactive/impulsive behaviour in VPT children may be explained by impairment in processing speed and working memory. Expected links between overactive/impulsive behaviour and inhibitory control were not identified, suggesting the nature of such difficulties may be different in VPT compared to term children.  相似文献   
206.

Background

The development of appropriate preventive measures aimed at the promotion of psychosocial capabilities and health behavior is based on the recognition that unemployment is associated with many physical, psychological and social problems.

Objective

A group program ??promotion of health and psychosocial self-efficacy in long-term unemployed?? was developed and investigated with respect to the effectiveness by a study group at the Clinic for Psychosomatic Medicine of the University of Rostock. The study was part of a project funded by the European Social Fund (ESF).

Methods

During the period from October 2009 to April 2010 the group program was implemented in 5 different groups and the sample included a total of 35 persons. To examine the effectiveness of the program the participants had to complete standardized questionnaires at the beginning and at the end of the program. Information as to what extent the unemployed suffer from mental stress was collected via the brief symptom inventory (BSI; Franke 2000). The questionnaire on resources and self-management skills (FERUS; Jack 2007) was applied to analyze the capabilities and the self-management skills of the participants.

Results

The unemployed subjects reported lower levels of aggressiveness and paranoid thinking (distrust) after their participation in the program. Regarding the self-management skills the participants improved their coping skills, self-instructions skills and also felt more hopeful with regard to their current environment and the future.

Conclusions

A systematic support of unemployed people regarding coping with the psychosocial problems associated with unemployment seemed to be important. The use of low structured group programs is a good possibility to implement them in different contexts with relatively few resources.  相似文献   
207.
Mutations in the amyloid precursor protein (APP) gene inducing abnormal processing and deposition of beta-amyloid protein in the brain have been implicated in the pathogenesis of Alzheimer's disease (AD). Although Tg2576 mice with the Swedish mutation (hAPPswe) exhibit age-related Abeta-plaque formation in brain regions like the hippocampus, the amygdala, and the cortex, these mice show a rather specific deficit in hippocampal-dependent learning and memory tasks. In view of recent findings showing that neural systems subserving different forms of learning are not simply independent but that depressing or enhancing one system affects learning in another system, we decided to investigate fronto-striatal synaptic plasticity and related procedural learning in these mutants. Fronto-striatal long-term depression (LTD) induced by tetanic stimulation of the cortico-striatal input was similar in Tg2576 and wild-type control mice. Behavioral data, however, pointed to an enhancement of procedural learning in the mutants that showed robust motor-based learning in the cross maze and higher active avoidance scores. Thus, in this mouse model of AD, an intact striatal function associated with an impaired hippocampal function seems to provide neural conditions favorable to procedural learning. Our results suggest that focusing on preserved or enhanced forms of learning in AD patients might be of interest to describe the functional reorganization of the brain when one memory system is selectively compromised by neurological disease.  相似文献   
208.
In Studies 1 and 2, the authors evaluated deliberate practice theory through analyses of the relationship between practice and performance for 2 populations of athletes: triathletes and swimmers, respectively. In Study 3, the authors obtained evaluations of practice from athletes' diaries. Across athletes, length of time involved in fitness activities was not related to performance. For the triathletes, a significant percentage of variance in performance was captured by practice. This was not so for sprint events for the swimmers, in which gender was a significant predictor. In the diaries, physical activities were perceived as enjoyable. In contrast to the results obtained from questionnaires, enjoyment did not covary with an activity's relevance to improving performance. Although these findings highlight the importance of sport-specific practice, the authors question a domain-independent account of expertise based on deliberate practice.  相似文献   
209.
Conditioned behavior as observed during classical conditioning in a group of identically treated animals provides insights into the physiological process of learning and memory formation. However, several studies in vertebrates found a remarkable difference between the group-average behavioral performance and the behavioral characteristics of individual animals. Here, we analyzed a large number of data (1640 animals) on olfactory conditioning in the honeybee (Apis mellifera). The data acquired during absolute and differential classical conditioning differed with respect to the number of conditioning trials, the conditioned odors, the intertrial intervals, and the time of retention tests. We further investigated data in which animals were tested for spontaneous recovery from extinction. In all data sets we found that the gradually increasing group-average learning curve did not adequately represent the behavior of individual animals. Individual behavior was characterized by a rapid and stable acquisition of the conditioned response (CR), as well as by a rapid and stable cessation of the CR following unrewarded stimuli. In addition, we present and evaluate different model hypotheses on how honeybees form associations during classical conditioning by implementing a gradual learning process on the one hand and an all-or-none learning process on the other hand. In summary, our findings advise that individual behavior should be recognized as a meaningful predictor for the internal state of a honeybee--irrespective of the group-average behavioral performance.  相似文献   
210.
If people are shown a dynamic movie of an action such as kicking a soccer ball or hitting a tennis ball, they will respond to it faster if it requires the same effector. This standard congruency effect was reported to reverse when participants viewed static images of famous athletes not actually performing an action. It was suggested that the congruent response was inhibited because of a social contrast effect, based on an implied action, whereby responders viewed themselves as comparatively worse than the professional athlete. The present study recorded hand and foot responses when identifying static images of both famous and novice athletes in soccer and tennis. The action was either explicit or implied. In Experiment 1, a standard congruency effect was found for all images. In Experiment 2, when a response was based on the identity of the athlete rather than their expertise, the standard congruency effect was enhanced for images of novice athletes, but was eliminated for experts, suggesting a social contrast effect. Our study is the first to show that embodiment effects can be seen for implied and explicit action images of both novices and experts, and that static images are capable of eliciting priming effects associated with sport-relevant effector pairings.  相似文献   
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