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811.
812.
Several studies have found that Hispanic Americans have higher rates of posttraumatic stress disorder (PTSD) than non-Hispanic Caucasian and Black Americans. The authors identified predictors of PTSD symptom severity that distinguished Hispanic police officers (n=189) from their non-Hispanic Caucasian (n=317) and Black (n=162) counterparts and modeled them to explain the elevated Hispanic risk for PTSD. The authors found that greater peritraumatic dissociation, greater wishful thinking and self-blame coping, lower social support, and greater perceived racism were important variables in explaining the elevated PTSD symptoms among Hispanics. Results are discussed in the context of Hispanic culture and may be important for prevention of mental illness in the fastest growing ethnic group in the United States.  相似文献   
813.
The Role of Temperament in the Etiology of Child Psychopathology   总被引:16,自引:0,他引:16  
A substantial proportion of children and adolescents come to suffer from psychological disorders. This article focuses on the temperament factors that are involved in the pathogenesis of child psychopathology. It is argued that besides the reactive temperament factor of emotionality/neuroticism, the regulative process of effortful control also plays an important role in the etiology and maintenance of internalizing and externalizing problems in youths. More specifically, vulnerability to child psychopathology is determined by a temperament that is characterized by high levels of emotionality/neuroticism and low levels of effortful control. Models are hypothesized in which reactive and regulative temperament factors either have interactive or additive effects on the development of psychological disorders in children, and conceptualized in terms of a developmental psychopathology perspective. Directions for future research and clinical implications of this temperamental view on psychopathology are discussed.  相似文献   
814.
The history of drug/vaccine development has included major advances guided primarily by risk/benefit analyses concerning the innovative agent, not by evidence-based clinical trials (Phase I–IV). Because the approval for new drugs is hindered under the present process, the system requires restructuring. The Phase I/II study period should be more flexible, using the “environment of knowledge” about the new agent, plus risk/benefit assessments. Phase III, as presently constructed, does not add new adverse events data, it provides a narrower profile of drug efficacy than properly done Phase II studies, and placebo-controlled trials continue to raise unresolved ethical and social issues. Phase III studies should be abandoned for most drugs, and substituted with properly powered Phase II doseranging studies plus careful post-marketing surveillance. Phase III should be a penalty for poor drug development, not a regulatory requirement. To accomplish efficient drug development, greater cooperation between pharmaceutical companies and governments in developing clinical trials is needed rather than over-regulation. These changes will synchronize the drug development and regulatory process with the current rapid drug discovery process, reduce drug development time and cost, and improve patient care. The author is Adjunct Professor of Medicine, Weill Medical College of Cornell University, New York, New York, USA.  相似文献   
815.
Before accepting a configural or holistic account of visual perception, one should be sure that an analytic (elemental) account does not provide an equal or better explanation of the results. I suggest that when one forms a compound of a color and a line orientation with one element previously trained as an S+ and the other as an S–, the resulting transfer found will depend on the relative salience of the two elements, and most important, the similarity of the compound to each of the training stimuli. Thus, if a line orientation is placed on a colored background (a separable compound), it will appear more like the colored field used in training, and color will control responding. However, if the line itself is colored (an integral compound), the compound will appear more like the line used in training, and line orientation will control responding. Not only does this account do a better job of explaining the data but it is simpler and it is testable.  相似文献   
816.
Studies of great apes have revealed that they use manual gestures and other signals to communicate about distal objects. There is also evidence that chimpanzees modify the types of communicative signals they use depending on the attentional state of a human communicative partner. The majority of previous studies have involved chimpanzees requesting food items from a human experimenter. Here, these same communicative behaviors are reported in chimpanzees requesting a tool from a human observer. In this study, captive chimpanzees were found to gesture, vocalize, and display more often when the experimenter had a tool than when she did not. It was also found that chimpanzees responded differentially based on the attentional state of a human experimenter, and when given the wrong tool persisted in their communicative efforts. Implications for the referential and intentional nature of chimpanzee communicative signaling are discussed.  相似文献   
817.
818.
819.
An apparatus is described that accurately measures response times and video records hand movements during haptic object recognition using complex three-dimensional (3-D) forms. The apparatus was used for training participants to become expert at perceptual judgments of 3-D objects (Greebles) using only their sense of touch. Inspiration came from previous visual experiments, and therefore training and testing protocols that were similar to the earlier visual procedures were used. Two sets of Greebles were created. One set (clay Greebles) was hand crafted from clay, and the other (plastic Greebles) was machine created using rapid prototyping technology. Differences between these object creation techniques and their impact on perceptual expertise training are discussed. The full set of these stimuli may be downloaded from www.psychonomic.org/archive/.  相似文献   
820.
Although task switching is often considered one of the fundamental abilities underlying executive functioning and general intelligence, there is little evidence that switching is a unitary construct and little evidence regarding the relationship between brain activity and switching performance. We examined individual differences in multiple types of attention shifting in order to determine whether behavioral performance and fMRI activity are correlated across different types of shifting. The participants (n=39) switched between objects and attributes both when stimuli were perceptually available (external) and when stimuli were stored in memory (internal). We found that there were more switchrelated activations in many regions associated with executive control—including the dorsolateral and medial prefrontal and parietal cortices—when behavioral switch costs were higher (poor performance). Conversely, activation in the ventromedial prefrontal cortex (VMPFC) and the rostral anterior cingulate was consistently correlated with good performance, suggesting a general role for these areas in efficient attention shifting. We discuss these findings in terms of a model of cognitive-emotional interaction in attention shifting, in which reward-related signals in the VMPFC guide efficient selection of tasks in the lateral prefrontal and parietal cortices.  相似文献   
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