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This theoretical paper discusses the role of pretend play and games with rules in fostering children's self-regulation. It proposes several pathways through which play facilitates self-regulation processes. First, in play, children learn to inhibit their impulsive behaviour and follow rules which transform their behaviour from impulsive and spontaneous to mediated and voluntary. Second, play liberates children from situational constraints as children begin to act upon the meanings of objects as opposed to their immediate motivational valence. Third, children develop internal representations which guide their behaviour. Finally, play promotes verbal self-regulation as children are engaged in an ongoing dialogue with their partners in order to resolve differences in perspectives, to reach an agreement about roles, and to invent play rules. The paper further reviews empirical studies which explore the effect of play on inhibition, working memory, and private speech. The current status of play and implications for practice are discussed.  相似文献   
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This study assessed long-lasting consequences of repeated ethanol exposure during two different periods of adolescence on 1) baseline levels of social investigation, play fighting, and social preference and 2) sensitivity to the social consequences of acute ethanol challenge. Adult male and female Sprague-Dawley rats were tested 25 days after repeated exposure to ethanol (3.5 g/kg intragastrically [i.g.], every other day for a total of 11 exposures) in a modified social interaction test. Early-mid adolescent intermittent exposure (e-AIE) occurred between postnatal days (P) 25 and 45, whereas late adolescent intermittent exposure (l-AIE) was conducted between P45 and P65. Significant decreases in social investigation and social preference were evident in adult male rats, but not their female counterparts following e-AIE, whereas neither males nor females demonstrated these alterations following l-AIE. In contrast, both e-AIE and l-AIE produced alterations in sensitivity to acute ethanol challenge in males tested 25 days after adolescent exposure. Ethanol-induced facilitation of social investigation and play fighting, reminiscent of that normally seen during adolescence, was evident in adult males after e-AIE, whereas control males showed an age-typical inhibition of social behavior. Males after l-AIE were found to be insensitive to the socially suppressing effects of acute ethanol challenge, suggesting the development of chronic tolerance in these animals. In contrast, females showed little evidence for alterations in sensitivity to acute ethanol challenge following either early or late AIE. The results of the present study demonstrate a particular vulnerability of young adolescent males to long-lasting detrimental effects of repeated ethanol. Retention of adolescent-typical sensitivity to the socially facilitating effects of ethanol could potentially make ethanol especially appealing to these males, therefore promoting relatively high levels of ethanol intake later in life.  相似文献   
994.
Nutrition labels on pre-packaged foods have been widely used as a medium to foster healthier eating habits in the general population, to contribute to a reduction in the incidence and prevalence of diet-related conditions. Yet, there is no convincing evidence that food labels are an effective means to achieve the desired effect at population level. Several factors have been suggested to account for this decoupling of efficacy, e.g. difficulties in understanding the information on food-labels. The present article presents the results of a survey on Europeans’ understanding of nutritional labels and evaluation on the communication tools for their diffusion. A total of 7550 phone interviews were conducted in 16 European Countries: Austria, Belgium, Denmark, France, Germany, Greece, Italy, the Netherlands, Poland, Portugal, Czech Republic, Slovenia, Spain, Sweden, United Kingdom and Hungary. Consumers were asked about their opinion on nutritional information provided at different levels and their commitment to healthy behaviour.  相似文献   
995.
Determining the minimum image resolution needed for clinical assessment is crucial for computational efficiency, image standardization, and storage needs alleviation. In this paper, we explore the image resolution requirements for the assessment of alopecia by analyzing how clinicians detect the presence of characteristics needed to quantify the disorder in the clinic. By setting the image resolution as a function of width of the patient’s head, we mimicked experiments conducted in the computer vision field to understand human perception in the context of scene recognition and object detection and asked 6 clinicians to identify the regions of interest on a set of retrospectively collected de-identified images at different resolutions. The experts were able to detect the presence of alopecia at very low resolutions, while significantly higher resolution was required to identify the presence of vellus-like hair. Furthermore, the accuracy with which alopecia was detected as a function of resolution followed the same trend as the one obtained when we classified normal versus abnormal hair density using a standard neural network architecture, hinting that the resolution needed by an expert human observer may also provide an upper bound for future image processing algorithms.  相似文献   
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The Val158Met rs4680 single-nucleotide polymorphism (SNP) at the catechol-O-methyltransferase (COMT) gene, primarily involved in dopamine breakdown within prefrontal cortex, has shown relations with inhibitory control (IC) in both adults and children. However, little is known about how COMT genotype relates to developmental trajectories of IC throughout childhood. Here, our study explored the effects of the COMT genotype (Val/Val, Val/Met, and Met/Met) on IC trajectories between the ages of 5 and 10 years. Children (n = 222) completed a Go/Nogo task at ages 5, 7, and 10; IC was characterized using signal detection theory to examine IC performance (d′) and response strategy (RS) (criterion). COMT genotype was not related to initial levels of IC performance and RS at age 5 or change in RS from ages 5 to 10. In contrast, COMT genotype was related to change in IC performance between 5 and 10 years. While Val/Val children did not differ from Val/Met children in development of IC performance, children with the Met/Met genotype exhibited more rapid development of IC performance when compared with Val/Met peers. These results suggest that COMT genotype modulates the development of IC performance in middle childhood.  相似文献   
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