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881.
The September 11, 2001, attack on New York City was the largest human-made disaster in United States history. In the first few days after the attack, it became clear that the scope of the attacks (including loss of life, property damage, and financial strain) was unprecedented and that the attacks could result in substantial psychological sequelae in the city population. Researchers at the Center for Urban Epidemiologic Studies at the New York Academy of Medicine designed and implemented an assessment of the mental health of New Yorkers 5-8 weeks after the attacks. To implement this research in the immediate postdisaster period, researchers at the center had to develop, in a compressed time interval, new academic collaborations, links with potential funders, and unique safeguards for study respondents who may have been suffering from acute psychological distress. Results of the assessment contributed to a New York state mental health needs assessment that secured Federal Emergency Management Agency funding for mental health programs in New York City. This experience suggests that mechanisms should be in place for rapid implementation of mental health assessments after disasters.  相似文献   
882.
Verbal declarative memory is one of the most reliably impaired cognitive functions in schizophrenia. Important issues are whether the problem is reversible, and which brain regions underlie improvement. We showed previously that glucose administration improved declarative memory in patients with schizophrenia, and sought in this pilot study to identify whether glucose affects the location or degree of activation of brain regions involved in a verbal encoding task. Seven clinically stable and medicated patients with schizophrenia or schizoaffective disorder, who showed deficits on a clinical test of memory, participated in the study. Subjects served as their own controls in a double-blind, crossover protocol that consisted of two sessions about a week apart. In each session, subjects ingested a beverage flavored with lemonade that contained 50 g of glucose on one occasion, and saccharin on the other. Blood glucose was measured before and 15, 50, and 75 min after ingestion. After ingesting the beverage, they performed a verbal encoding task while undergoing brain functional magnetic resonance imaging. The results showed significantly greater activation of the left parahippocampus during novel sentence encoding in the glucose condition, compared to the saccharin condition, despite no change in memory performance. A trend towards greater activation of the left dorsolateral prefrontal cortex (p<.07) was also evident in the glucose condition. These pilot findings emphasize the sensitivity of both the medial temporal and prefrontal regions to effects of glucose administration during encoding, and are consistent with the hypothesis that these regions also participate in declarative memory improvements following glucose administration.  相似文献   
883.
We explore the neurobiological bases of attention deficit hyperactivity disorder (ADHD) from the viewpoint of the neurochemistry and psychopharmacology of the catecholamine-based behavioural systems. The contributions of dopamine (DA) and noradrenaline (NA) neurotransmission to the motor and cognitive symptoms of ADHD (e.g. hyperactivity, variable and impulsive responses) are studied in rodent and primate models. These models represent elements of the behavioural units observed in subjects with ADHD clinically, or in laboratory settings (e.g. locomotion, changed sensitivity/responsivity to novelty/reinforcement and measures of executive processing). In particular, the models selected emphasize traits that are strongly influenced by mesocorticolimbic DA in the spontaneously hypertensive (SHR) and the Naples high excitability (NHE) rat lines. In this context, the mode of action of methylphenidate treatment is discussed. We also describe current views on the altered control by mesolimbic catecholamines of appropriate and inappropriate goal-directed behaviour, and the tolerance or intolerance of delayed reinforcement in ADHD children and animal models. Recent insights into the previously underestimated role of the NA system in the control of mesocortical DA function, and the frontal role in processing information are elaborated.  相似文献   
884.
The present study examines changes in adolescents’ body image over a 10-year period. Both satisfaction with appearance in general, and satisfaction with different aspects of appearance (e.g., face, muscle tone, and weight) are considered. We analyzed data from two general population studies of 13–19-year-old Norwegians, “Young in Norway 1992” (N = 10,460, response rate = 97.0%) and “Young in Norway 2002” (N = 11,371, response rate = 92.3%). These studies used identical sampling procedures, data collection procedures, and measures of body image. The analyses showed a polarization in adolescents’ body image — concurrent with an increase in the proportion of adolescents with a very negative body image, there was an increase in the proportion of adolescents with a very positive body image. The greater proportion of adolescents with a very negative body image could partly be explained statistically by the increased body mass index (BMI) in the same period. Girls had a more problematic body image than boys, both in 1992 and in 2002. Whether the strength of this gender difference changed or not depended on the aspect of appearance considered.  相似文献   
885.
Beginning with the assumption that implicit theories of personality are crucial tools for understanding social behavior, the authors tested the hypothesis that perceivers would process person information that violated their predominant theory in a biased manner. Using an attentional probe paradigm (Experiment 1) and a recognition memory paradigm (Experiment 2), the authors presented entity theorists (who believe that human attributes are fixed) and incremental theorists (who believe that human attributes are malleable) with stereotype-relevant information about a target person that supported or violated their respective theory. Both groups of participants showed evidence of motivated, selective processing only with respect to theory-violating information. In Experiment 3, the authors found that after exposure to theory-violating information, participants felt greater anxiety and worked harder to reestablish their sense of prediction and control mastery. The authors discuss the epistemic functions of implicit theories of personality and the impact of violated assumptions.  相似文献   
886.
This article examines the impact of the school-based smoking-prevention program "BE smokeFREE" on adolescent smoking. A national representative sample of 99 schools (195 classes, 4,441 students) was used when the intervention started in November 1994. Schools were allocated to one of four groups: a comparison group (A) and three intervention groups (B, C, and D). Group B received the most comprehensive intervention. A baseline (autumn 1994) and three follow-up data collections (1995, 1996, and 1997) were conducted. There were no significant differences in smoking habits among the four groups at baseline. The smoking habits in the group that was involved in the most comprehensive intervention (group B) changed more favourably than those of students in the comparison schools over the three follow-up data collections. At the third follow-up, the proportion of students smoking weekly or more in the comparison group was 29.2%, compared with 19.6% in the model intervention group. The two less comprehensive interventions (no teacher in-service courses in group C, and no involvement of parents in group D) appeared to be less effective than the model intervention. Multilevel multiple logistic regression analyses, comparing changes in smoking habits between students in group B with those among students in the comparison schools, confirm the conclusion that the comprehensive intervention was the most effective. This school-based intervention, based on a social influence approach, proved to be effective at reducing smoking rates among participants.  相似文献   
887.
This article examines the human face as a transmitter of expression signals and the brain as a decoder of these expression signals. If the face has evolved to optimize transmission of such signals, the basic facial expressions should have minimal overlap in their information. If the brain has evolved to optimize categorization of expressions, it should be efficient with the information available from the transmitter for the task. In this article, we characterize the information underlying the recognition of the six basic facial expression signals and evaluate how efficiently each expression is decoded by the underlying brain structures.  相似文献   
888.
The relationships between exposure to violence at work, sense of coherence, and stress reactions were analysed in a large sample of the Danish workforce. The results showed that employees subjected to violence have a weaker sense of coherence than the rest of the respondents. Sense of coherence acted as a mediator and not as a moderator of relationships between exposure to violence and psychological, psychosomatic and cognitive stress reactions. The stability of the sense of coherence construct is discussed. With respect to the relation between sense of coherence and violence, preventative measures at the individual and organizational level are suggested.  相似文献   
889.
The present study examined the relations between indicators of emotional processing (e.g. trauma narratives), posttraumatic stress symptoms, and psychological distress in two military samples (N = 120) exposed to significant training accidents. Trauma narratives were collected at 2-3 weeks, while outcome measures (e.g. IES-15, PTSS-10, and GHQ-30) were collected at 2-3 weeks, and 4 months after the accidents. Emotional processing was indexed by the content of positive and negative emotional expressions in the trauma narratives. The results showed that positive emotional expressions were associated with lower levels of psychological distress, whereas negative emotional expressions were linked to trauma specific symptoms and psychological distress at 2-3 weeks. Negative emotional expressions explained between 6-8% of the variance in trauma specific symptoms at 2-3 weeks, and 11% of the variance in psychological distress symptoms at 4 months after the traumatic event.  相似文献   
890.
The authors trained pigeons to discriminate images of human faces that displayed: (a) a happy or a neutral expression or (b) a man or a woman. After training the pigeons, the authors used a new procedure called Bubbles to pinpoint the features of the faces that were used to make these discriminations. Bubbles revealed that the features used to discriminate happy from neutral faces were different from those used to discriminate male from female faces. Furthermore, the features that pigeons used to make each of these discriminations overlapped those used by human observers in a companion study (F. Gosselin & P.G. Schyns, 2001). These results show that the Bubbles technique can be effectively applied to nonhuman animals to isolate the functional features of complex visual stimuli.  相似文献   
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