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991.
Science policy mandates across the industrialized world insinuate more active roles for publics, their earlier participation in policy decisions, and expanded notions of science and technology governance. In response to these policies, engaged scholars in science studies have sought to design and conduct exercises aimed at better attuning science to its public contexts. As demand increases for innovative and potentially democratic forms of public engagement with science and technology, so also do the prospects for insights from science studies to contribute to policy agendas and institutional capabilities. This collection brings together an international set of scholars in science, technology and society who inquire into the meaning, efficacy and responsibility of engaged science studies scholarship as a public matter.  相似文献   
992.
Functional magnetic resonance imaging was used to examine functional anatomy of attention to social (eye gaze) and nonsocial (arrow) communicative stimuli in late childhood and in a disorder defined by atypical processing of social stimuli, Autism Spectrum Disorders (ASD). Children responded to a target word ('LEFT'/'RIGHT') in the context of a distracting arrow or averted gaze pointing in a direction that was congruent, incongruent, or neutral (bar without arrowheads, central gaze) relative to the target word. Despite being irrelevant to the target task, both arrow and averted gaze facilitated responses (Congruent vs. Neutral trials) to the same extent in the two groups and led to interference (Incongruent vs. Congruent trials), which was greater from arrows in ASD than control children. In the brain, interaction between group and distracter-domain was observed in frontal-temporal regions during facilitation and frontal-striatal regions during interference. During facilitation, regions associated with attention to gaze in control children (left superior temporal sulcus, premotor) were associated with attention to arrows in ASD children; gaze was associated with medial temporal involvement in ASD children. During interference, regions associated with arrows in control children (anterior cingulate, right caudate) were activated in response to gaze in ASD children; further, left dorsolateral prefrontal cortex, a region not observed in control children, was activated during gaze-interference in ASD children. Thus, functional anatomy was atypical in ASD children during spontaneous processing of social and nonsocial communicative cues.  相似文献   
993.
Whereas positive emotions and feeling unequivocally good may be at the heart of well-being among Westerners, positive emotions often carry negative associations within many Asian cultures. Based on a review of East-West cultural differences in dialectical emotions, or co-occurring positive and negative feelings, we predicted culture to influence the association between positive emotions and depression, but not the association between negative emotions and depression. As predicted, in a survey of over 600 European-, immigrant Asian-, and Asian American college students, positive emotions were associated with depression symptoms among European Americans and Asian Americans, but not immigrant Asians. Negative emotions were associated with depression symptoms among all three groups. We also found initial evidence that acculturation (i.e., nativity) may influence the role of positive emotions in depression: Asian Americans fell "in between" the two other groups. These findings suggest the importance of studying the role of culture in positive emotions and in positive psychology. The use of interventions based on promoting positive emotions in clinical psychology among Asian clients is briefly discussed.  相似文献   
994.
995.
Previous studies examining event-related potentials and evaluative priming have been mixed; some find evidence that evaluative priming influences the N400, whereas others find evidence that it affects the late positive potential (LPP). Three experiments were conducted using either affective pictures (Experiments 1 and 2) or words (Experiment 3) in a sequential evaluative priming paradigm. In line with previous behavioral findings, participants responded slower to targets that were evaluatively incongruent with the preceding prime (e.g., negative preceded by positive) compared to evaluatively congruent targets (e.g., negative preceded by negative). In all three studies, the LPP was larger to evaluatively incongruent targets compared to evaluatively congruent ones, and there was no evidence that evaluative incongruity influenced the N400 component. Thus, the present results provide additional support for the notion that evaluative priming influences the LPP and not the N400. We discuss possible reasons for the inconsistent findings in prior research and the theoretical implications of the findings for both evaluative and semantic priming.  相似文献   
996.
Students were taught an algorithm for solving a new class of mathematical problems. Occasionally in the sequence of problems, they encountered exception problems that required that they extend the algorithm. Regular and exception problems were associated with different patterns of brain activation. Some regions showed a Cognitive pattern of being active only until the problem was solved and no difference between regular or exception problems. Other regions showed a Metacognitive pattern of greater activity for exception problems and activity that extended into the post-solution period, particularly when an error was made. The Cognitive regions included some of parietal and prefrontal regions associated with the triple-code theory of (Dehaene, S., Piazza, M., Pinel, P., & Cohen, L. (2003). Three parietal circuits for number processing. Cognitive Neuropsychology, 20, 487–506) and associated with algebra equation solving in the ACT-R theory (Anderson, J. R. (2005). Human symbol manipulation within an 911 integrated cognitive architecture. Cognitive science, 29, 313–342. Metacognitive regions included the superior prefrontal gyrus, the angular gyrus of the triple-code theory, and frontopolar regions.  相似文献   
997.
A chronic tendency to avoid novelty is often the result of a temperamental bias called inhibited temperament, and is associated with increased risk for anxiety disorders. Neuroimaging studies have demonstrated that an inhibited temperament is associated with increased amygdalar blood-oxygenation-level-dependent (BOLD) response to unfamiliar faces that were not expected; however, the effects of variations in expectancy remain unknown. Using functional magnetic resonance imaging (fMRI), we studied BOLD response to infrequently encountered fear faces that were either expected or not expected in 42 adults with an inhibited or an uninhibited temperament. Individuals with an inhibited temperament had greater amygdala, but less dorsal anterior cingulate cortex (dACC), BOLD response when the stimuli were expected. In contrast, those with an uninhibited temperament had a smaller amygdala but larger dorsal anterior cingulate cortex BOLD response when expecting to see fear faces. These findings demonstrate temperament differences in expectancy effects and provide preliminary evidence for the dACC as a neural substrate mediating differences in inhibited temperament. Enhanced amygdala sensitivity coupled with weak inhibitory control from the dACC may form a neural circuit mediating behaviors characteristic of inhibited temperament and risk for anxiety disorders.  相似文献   
998.
Autonomous agents are not so difficult to construct. Constructing autonomous agents that will work as required is much harder. A clear way in which we can design and analyse autonomous systems so that we can be more confident that their behaviour is as required is to use formal methods. These can, in principle, allow us to exactly specify the behaviour of the agent, and verify that any implementation has the properties required. In addition to using a more formal approach, it is clear that problems of conceptualisation and analysis can be aided by the use of an appropriate abstraction.In this article we tackle one particular aspect of formal methods for agent-based systems, namely the formal representation and implementation of deliberation within agents. The key aspect here is simplicity. Agents are specified using a relatively simple temporal logic and are executed by directly interpreting such temporal formulae. Deliberation is captured by modifying the way in which execution handles its temporal goals. Thus, in this article we provide motivations, theoretical underpinnings, implementation details, correctness arguments, and comparisons with related work.  相似文献   
999.
1000.
As the United States becomes increasingly diverse, interracial contact will become considerably less rare. Much research has suggested that interracial interactions are often stressful and uncomfortable for both Whites and racial minorities. Bringing together several bodies of research, the present article outlines a motivational perspective on the dynamics of intergroup contact. To this end, we consider the roles of three motivational mindsets that have the potential to shape interactions to be less cognitively depleting and more enjoyable for both interactants. In particular, we consider the effects of (i) approach and avoidance motivation (Handbook of Motivation and Cognition: Foundation of Social Behavior, 1990, New York: Guilford Press), (ii) promotion and prevention regulatory focus (American Psychologist, 52 , 1997, 1280), and (iii) learning and performance goals (Psychological Review, 95 , 1988, 256) in shaping the dynamics of interracial contact. We suggest that investigations into these motivational mindsets will offer further insight into how and why interracial interactions go awry and will assist in the development of strategies and interventions that facilitate more smooth and enjoyable contact experiences.  相似文献   
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