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81.
A grandmaster and an international chess master were compared with a group of novices in a memory task with chess and non-chess stimuli, varying the structure and familiarity of the stimuli, while functional magnetic resonance images were acquired. The pattern of brain activity in the masters was different from that of the novices. Masters showed no differences in brain activity when different degrees of structure and familiarity where compared; however, novices did show differences in brain activity in such contrasts. The most important differences were found in the contrast of stimulus familiarity with chess positions. In this contrast, there was an extended brain activity in bilateral frontal areas such as the anterior cingulate and the superior, middle, and inferior frontal gyri; furthermore, posterior areas, such as posterior cingulate and cerebellum, showed great bilateral activation. These results strengthen the hypothesis that when performing a domain-specific task, experts activate different brain systems from that of novices. The use of the experts-versus-novices paradigm in brain imaging contributes towards the search for brain systems involved in cognitive processes.  相似文献   
82.
We are often aware of the content of distracting sound, although typically remain unaware of the processes by which that sound is disruptive. Disruption can occur even when the sound is ignored and unrelated to the task being performed. In a recent major development, Gisselg?rd et al. have used positron emission tomography to reveal how distracting sounds recruit the involvement of dorsolateral prefrontal cortex.  相似文献   
83.
Non-invasive mapping of brain structure and function with magnetic resonance imaging (MRI) has opened up unprecedented opportunities for studying the neural substrates underlying cognitive development. There is an emerging consensus of a continuous increase throughout adolescence in the volume of white matter, both global and local. There is less agreement on the meaning of asynchronous age-related decreases in the volume of grey matter in different cortical regions; these might equally represent loss ("pruning") or gain (intra-cortical myelination) of tissue. Functional MRI studies have so far focused mostly on executive functions, such as working memory and behavioural inhibition, with very few addressing questions regarding the maturation of social cognition. Future directions for research in this area are discussed in the context of processing biological motion and matching perceptions and actions.  相似文献   
84.
Some children living with life-shortening medical conditions may wish to attend school without the threat of having resuscitation attempted in the event of cardiopulmonary arrest on the school premises. Despite recent attention to in-school do-not-attempt-resuscitation (DNAR) orders, no assessment of state laws or school policies has yet been made. We therefore sought to survey a national sample of prominent school districts and situate their policies in the context of relevant state laws. Most (80%) school districts sampled did not have policies, regulations, or protocols for dealing with student DNARs. A similar majority (76%) either would not honor student DNARs or were uncertain about whether they could. Frequent contradictions between school policies and state laws also exist. Consequently, children living with life-shortening conditions who have DNARs may not have these orders honored if cardiopulmonary arrest were to occur on school premises. Coordinated efforts are needed to harmonize school district, state, and federal approaches in order to support children and families' right to have important medical decisions honored.  相似文献   
85.
Declining communication skills in dementia threaten a person's sense of self. Building on enduring capabilities, pastoral visitors can significantly enhance spiritual well-being through the use of individualized, person-centered strategies. This article outlines the primary spiritual needs of older adults with dementia and some general strategies to improve communication based on enduring abilities. Detailed examples illustrate how these personhood-centered strategies can meet spiritual needs by connecting with individuals with dementia through life stories and through helping them to participate in religious life.  相似文献   
86.
87.
The mental number line: exact and approximate   总被引:1,自引:0,他引:1  
Fias W  Verguts T 《Trends in cognitive sciences》2004,8(10):447-8; author reply 448-9
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88.
The endowment effect occurs when ownership of a good leads consumers to value the good more than its market value. Students who were given College of Business Administration insignia mugs to keep valued them significantly more than students who were given the same mugs to examine and return (nonendowment condition). The endowment effect also occurred for plain white mugs. Students who were given plain white mugs to keep valued them more than students who were given the same mugs to examine and return. Ownership of insignia mugs not only resulted in the endowment effect but also resulted in an institutional affinity effect: Students provided higher satisfaction ratings with the College of Business Administration than did students endowed with plain white mugs and students in nonendowed conditions. This study demonstrates the impact of the endowment effect on institutional affinity for insignia goods. However, the tandem endowment-affinity effect occurs at the attitude formation stage, not when an attitude has already been formed.  相似文献   
89.
Relations of overt and relational aggression with perceived popularity among children and early adolescents were examined in 2 studies (Ns = 607 and 1,049). Among older youths, positive concurrent relations found between overt aggression and perceived popularity became nonsignificant when relational aggression was controlled, whereas positive associations found between relational aggression and perceived popularity held when overt aggression was controlled. Aggression and perceived popularity were not positively related for the younger participants. The 2nd study also examined the temporal ordering of these relations over 6 months. For older girls, positive relations between relational aggression and perceived popularity were bidirectional. For older boys, relational aggression did not predict increased perceived popularity, but perceived popularity predicted increased relational aggression. Implications for intervention are discussed.  相似文献   
90.
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