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The authors tested effects of a 10-week group cognitive-behavioral stress management intervention among 100 women newly treated for Stage 0-II breast cancer. The intervention reduced prevalence of moderate depression (which remained relatively stable in the control condition) but did not affect other measures of emotional distress. The intervention also increased participants' reports that having breast cancer had made positive contributions to their lives, and it increased generalized optimism. Both remained significantly elevated at a 3-month follow-up of the intervention. Further analysis revealed that the intervention had its greatest impact on these 2 variables among women who were lowest in optimism at baseline. Discussion centers on the importance of examining positive responses to traumatic events--growth, appreciation of life, shift in priorities, and positive affect-as well as negative responses.  相似文献   
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Cognitive neuropsychology provides a theoretical framework and methods that can be of value in the study of developmental disorders, but the "dissociation" logic at the centre of this approach is not well suited to the developmental context. This is illustrated with examples from specific language impairment. Within the developing language system there is ample evidence for interaction between levels of representation, with modularity emerging in the course of development. This means that one typically is seeking to explain a complex pattern of associated impairments, rather than highly selective deficits. For instance, a selective impairment in auditory processing can have repercussions through the language system and may lead to distinctive syntactic deficits that are seen in written as well as spoken language. Changes in the nature of representations and in the relationships between components of a developing system mean that cross-sectional data at a single point in development may be misleading indicators of the primary deficit. Furthermore, traditional cognitive neuropsychology places a disproportionate emphasis on representational (competence) deficits, with processing (performance) deficits being relatively neglected. Methods for distinguishing these two kinds of impairment are discussed, as well as other approaches for elucidating the underlying nature of developmental disorders.  相似文献   
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Previous research demonstrates that older adults are poor at dual tasking, but there is less agreement on whether their decrement is worse than that predicted from single-task performance. This study investigated whether task domain moderates dual-task costs in old age. In two experiments, young and older adults retrieved either previously learned associates (episodic retrieval) or overlearned category members (semantic retrieval) under single or working-memory load conditions, using cued recall (Experiment 1) and recognition (Experiment 2) procedures. In both experiments the proportional costs of dual tasking were age invariant for semantic retrieval but were particularly marked for episodic retrieval, although the size of the age effect was reduced in recognition compared to cued recall. The data suggest that age effects in dual tasking may be domain specific.  相似文献   
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Three experiments, each using a single group of pigeons, are reported. In Experiment 1 subjects were initially trained with two stimuli, one of which was always followed by food, the other being reinforced according to a 50% partial reinforcement schedule. Subsequently a serial procedure was adopted in which an additional stimulus, C, was consistently followed by the partially reinforced CS. A second additional stimulus, A, was followed on half of its occurrences by the continuously reinforced CS, its remaining presentations being followed by nothing. The rate of autoshaped keypecking was substantially greater during A than during C. In the remaining experiments subjects received first-order conditioning with a single stimulus that was either partially (Experiment 2) or continuously (Experiment 3) reinforced. The stimuli A and C were then again introduced for serial autoshaping. Stimulus A was occasionally paired with the CS and occasionally followed by nothing, whereas stimulus C was always followed by the CS. As in Experiment 1, the rate of responding during A was greater than during C. It is proposed that one influence on the rate of autoshaped keypecking during a CS is the accuracy with which the immediate consequences of that CS are predicted.  相似文献   
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Brain mapping studies using dynamic imaging methods demonstrate areas regional cerebral blood flow (rCBF) decreases, as well as areas where increases, during performance of various experimental tasks. Task holds for both sets of cerebral blood flow changes (CBF), providing the opportunity to investigate areas that become and “activated” in the experimental condition relative to control state. Such data yield the intriguing observation that in areas in emotional processing, such as the amygdala, the posteromedial cortex, and the ventral anterior cingulate cortex, although flow as expected during specific emotion-related tasks, flow decreases performance of some attentionally demanding, cognitive tasks. Conversely, in some of the areas that appear to subserve cognitive functions, as the dorsal anterior cingulate and the dorsolateral prefrontal cortices, increases while performing attentionally demanding cognitive tasks, but during some experimentally induced and pathological emotional Although the specific nature of such reciprocal patterns of regional remains unclear, they may reflect an important cross-modal interaction during mental operations. The possibility that neural activity is less in areas required in emotional processing during some higher cognitive processes holds implications for the mechanisms underlying interactions cognition and emotion. Furthermore, the possibility that neural in some cognitive-processing areas is suppressed during intense states suggests mechanisms by which extreme fear or severe may interfere with cognitive performance.  相似文献   
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