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971.
Depression After Traumatic Brain Injury: A Review of Evidence for Clinical Heterogeneity 总被引:3,自引:0,他引:3
Depression represents a major source of disability among individuals who have suffered a traumatic brain injury (TBI), with estimates of prevalence in this population ranging over 50%. In comparison with other sequelae of TBI, depression is often poorly conceptualized and treated among acute care and rehabilitation professionals. One reason for this is the lack of clear etiological models for the development of depression following TBI. This paper argues that post-TBI depression actually represents a heterogeneous category, with multiple etiologic pathways and clinical implications. The literature in this area is reviewed, with an emphasis on an appreciation of the diversity within this clinical population. Conclusions focus on suggestions for differential diagnosis and treatment options. 相似文献
972.
Recently, several researchers and philosophers argued that clinical research trials are not therapy. Their position is based on foundational research ethics documents, such as the Belmont Report, on conceptual analysis, and on the general way clinical trials are conducted. After examining and rejecting these arguments, we claim that good research is consistent with good therapy; that often trials are good therapy; and that a blanket attack on clinical trials as non-therapeutic creates a research misconception. This misconception is potentially harmful because it could weaken trial recruitment, could adversely affect funding for trials, and could overturn needed moral safeguards on therapeutic trials. Our more careful and accurate analysis of the nature of clinical trials can avoid such problems. 相似文献
973.
Family context is thought to influence chronic disease management but few studies have longitudinally examined these relationships. Research on families and chronic illness has focused almost exclusively on European American families. In this prospective study we tested a multidimensional model of family influence on disease management in type 2 diabetes in a bi-ethnic sample of European Americans and Latinos. Specifically, we tested how baseline family characteristics (structure, world view, and emotion management) predicted change in disease management over one year in 104 European American and 57 Latino patients with type 2 diabetes. We found that emotion management predicted change in disease management in both groups of patients as hypothesized, while family world view predicted change in both ethnic groups but in the predicted direction only for European Americans. Examining family context within ethnic groups is required to elucidate unique cultural patterns. Attending to culturally unique interpretations of constructs and measures is warranted. The import of family emotion management, specifically conflict resolution, in disease management deserves further study to support clinical intervention development. Examining multiple domains of family life and multidimensional health outcomes strengthens our capacity to develop theory about family contexts and individual health. 相似文献
974.
Histidine-decarboxylase knockout mice show deficient nonreinforced episodic object memory, improved negatively reinforced water-maze performance, and increased neo- and ventro-striatal dopamine turnover
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Dere E De Souza-Silva MA Topic B Spieler RE Haas HL Huston JP 《Learning & memory (Cold Spring Harbor, N.Y.)》2003,10(6):510-519
The brain's histaminergic system has been implicated in hippocampal synaptic plasticity, learning, and memory, as well as brain reward and reinforcement. Our past pharmacological and lesion studies indicated that the brain's histamine system exerts inhibitory effects on the brain's reinforcement respective reward system reciprocal to mesolimbic dopamine systems, thereby modulating learning and memory performance. Given the close functional relationship between brain reinforcement and memory processes, the total disruption of brain histamine synthesis via genetic disruption of its synthesizing enzyme, histidine decarboxylase (HDC), in the mouse might have differential effects on learning dependent on the task-inherent reinforcement contingencies. Here, we investigated the effects of an HDC gene disruption in the mouse in a nonreinforced object exploration task and a negatively reinforced water-maze task as well as on neo- and ventro-striatal dopamine systems known to be involved in brain reward and reinforcement. Histidine decarboxylase knockout (HDC-KO) mice had higher dihydrophenylacetic acid concentrations and a higher dihydrophenylacetic acid/dopamine ratio in the neostriatum. In the ventral striatum, dihydrophenylacetic acid/dopamine and 3-methoxytyramine/dopamine ratios were higher in HDC-KO mice. Furthermore, the HDC-KO mice showed improved water-maze performance during both hidden and cued platform tasks, but deficient object discrimination based on temporal relationships. Our data imply that disruption of brain histamine synthesis can have both memory promoting and suppressive effects via distinct and independent mechanisms and further indicate that these opposed effects are related to the task-inherent reinforcement contingencies. 相似文献
975.
Current theories of confidence in human judgment assume that confidence and the decision it is based on are inextricably tied
to the same process (decisional locus theories) or that confidence processing begins only once the primary decision has been
completed (postdecisional locus theories). In the absence of auxiliary assumptions, however, neither class of theory permits
the judgment of confidence to affect primary decision processing. In the present study, we examined the effect of rendering
confidence judgments on the properties of the decision process in a sensory discrimination task. An examination of the properties
of the time taken to determine confidence (i.e., the time taken to render the judgment of confidence) revealed clear evidence
of postdecisional confidence processing. Concomitantly, the requirement of confidence judgments was found to substantially
increase decisional response times, suggesting that some confidence processing occurs during the primary decision process.
We discuss the implications of these findings for contemporary models of confidence in human judgment. 相似文献
976.
People with Williams syndrome process faces holistically 总被引:4,自引:0,他引:4
This study compared the performance of 47 adolescents and adults with Williams syndrome to 39 age-matched controls on a face recognition task. Using the whole-part paradigm developed by Tanaka and his colleagues, we found that although performance overall was lower in the participants with Williams syndrome, both groups showed similar patterns of performance across the different conditions. Both groups performed significantly better in the whole-face than in the isolated-part test condition for upright faces, but not for inverted faces. The whole-face advantage only in the upright condition provides strong evidence that people with Williams syndrome encode and recognize faces holistically in the same way as normal controls, suggesting the use of similar underlying neurocognitive mechanisms. These findings contradict earlier reports in the literature that people with Williams syndrome process faces abnormally. 相似文献
977.
Two experiments investigated the effect of test modality (visual or auditory) on source memory and event-related potentials (ERPs). Test modality influenced source monitoring such that source memory was better when the source and test modalities were congruent. Test modality had less of an influence when alternative information (i.e., cognitive operations) could be used to inform source judgments in Experiment 2. Test modality also affected ERP activity. Variation in parietal ERPs suggested that this activity reflects activation of sensory information, which can be attenuated when the sensory information is misleading. Changes in frontal ERPs support the hypothesis that frontal systems are used to evaluate source-specifying information present in the memory trace. 相似文献
978.
Leynes PA Marsh RL Hicks JL Allen JD Mayhorn CB 《Consciousness and cognition》2003,12(1):1-18; discussion 19-24; author reply 25-30
Strong evidence exists in the literature that remembering to complete intentions involves executive processing subserved by the frontal lobes. Event-related potentials were measured during the encoding of actions with the intention to perform versus more neutral material about which there was no such intentionality. Event-related potentials were also measured in a two-alternative discrimination task requiring identification of the to-be-performed actions and to-be-memorized actions. The results suggest that formation and retrieval of intentions differs from encoding and retrieval of similar material committed to memory. Additionally, the results suggest that right frontal areas may play an important role in the formation of prospective actions and that intentions are kept active in memory by processing mediated by the left frontal pole. 相似文献
979.
Two studies explored how domestic violence may be implicitly or explicitly sanctioned and reinforced in cultures where honor is a salient organizing theme. Three general predictions were supported: (a) female infidelity damages a man's reputation, particularly in honor cultures; (b) this reputation can be partially restored through the use of violence; and (c) women in honor cultures are expected to remain loyal in the face of jealousy-related violence. Study 1 involved participants from Brazil (an honor culture) and the United States responding to written vignettes involving infidelity and violence in response to infidelity. Study 2 involved southern Anglo, Latino, and northern Anglo participants witnessing a "live" incident of aggression against a woman (actually a confederate) and subsequently interacting with her. 相似文献
980.
Studies have shown that task sets could be configured endogenously (i.e., on the basis of memory) according to an explicit
sequence or exogenously according to a task cue. In two experiments, we examined whether an implicitly learned sequence could
facilitate task set configuration without participants’ intention. These experiments led to opposite conclusions regarding
this question, but their methodology made it impossible to distinguish between the interpretations. We altered the task-switching
paradigm by embedding a hidden task sequence, while randomizing all other aspects, including perceptual (i.e., task cues)
and motor elements. We found that a sequence of tasks, proper, was learned implicitly and that the memory of that sequence
endogenously facilitated task decision processes without the participants’ explicit knowledge. 相似文献