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861.
It is proposed that memory is organized into event-based, knowledge-based, and rule-based memory systems. Furthermore, each system is composed of the same set of multiple attributes and characterized by a set of process oriented operating characteristics that are mapped onto multiple neural regions and interconnected neural circuits. Based on this theoretical model of memory, it is possible to investigate the independence and interaction among brain regions between any two systems for any of the proposed attributes or processes. This applies also to the investigation of independence and interactions between any two attributes within a system and between processes associated with a system for any of the proposed attributes. In this article, research evidence is presented to suggest that there are both dissociations and interactions between the hippocampus and caudate nucleus in mediating spatial and response attributes within the event-based memory system, between the hippocampus and the parietal cortex in subserving the spatial attribute within the event-based and knowledge-based memory systems, and between the hippocampus and the prefrontal cortex in subserving the spatial attribute within the event-based and rule-based memory systems.  相似文献   
862.
Since the identification of the FMR1 gene basic research has been focused on the molecular characterization of the FMR1 gene product, the fragile X mental retardation protein (FMRP). Recent developments in fragile X research have provided new insights and knowledge about the physiological function of FMRP in the cell and the nerve cell in particular. Currently, compelling evidence suggests a role for FMRP in the transport/translation of dendritically localized mRNAs. In addition, the identification of some of the target mRNAs of FMRP have led to an increased interest in the neurobiology of the syndrome. This review highlights the role of FMRP in dendritic mRNA transport/translation in relation to synaptic plasticity, a molecular mechanism implicated in learning and memory.  相似文献   
863.
In recent years, considerable discussion has occurred about stigma surrounding the name given to an illness currently known as chronic fatigue syndrome (CFS). Although patients and medical personnel have expressed varying opinions on this issue, no studies have evaluated how beliefs about the illness change based upon the type of name used for diagnostic purposes. Proposals have been put forth to rename the illness with an eponym (a famous patient's or researcher's name) or with a less trivial sounding, more medically based type of name. In this study, attributions about CFS were measured in three groups of medical trainees. All groups read the same case study of a person with classic symptoms of chronic fatigue syndrome, with the only difference being in the type of name given. Trainees then were asked to provide attributions about certain aspects of the illness, including its cause, severity, and prognosis. Results suggested that, across name conditions, most trainees appeared to consider the symptom complex of CFS a serious illness resulting in poor quality of life. In addition, findings indicated that the name, chronic fatigue syndrome, may be regarded less seriously than the Myalgic Encephalopathy name with respect to some important aspects of the illness. In this study, specialty of medical trainee also played a role in how the illness was perceived.  相似文献   
864.
The incremental contribution of the MMPI-A (Butcher et al., 1992) content scales to the prediction of scores on self-report measures of psychopathology was examined in a sample of 62 adolescents in inpatient treatment and 59 adolescents from the community. All participants completed the MMPI-A and a battery of criterion measures. A series of hierarchical regression analyses was conducted in which the MMPI-A clinical and content scales served as the independent variables and the criterion measures as the dependent variables. The content scales were found to have incremental validity beyond the clinical scales in predicting variance in the criterion measures. Similarly, the clinical scales also demonstrated incremental validity over the content scales in making these predictions. Both sets of scales made independent contributions to the prediction of sample membership (clinical vs. nonclinical). Findings suggest that both the clinical and content scales of the MMPI-A make significant contributions to the assessment of adolescents' psychological functioning.  相似文献   
865.
Previous studies of event-based prospective memory have demonstrated that the character of an ongoing task can affect cue detection. By contrast, this study demonstrated that there is a reciprocal relationship insofar as cue-verification and response-retrieval processes interfered with making a response in the ongoing task. The amount of interference was determined by the type of intention, which was manipulated to affect the complexity of verification and retrospective response retrieval. These relationships were true even when the interference caused by cue detection was separated from a more general effect to ongoing-task performance caused by shifts in attentional allocation policies. The results have theoretical implications for models that attempt to specify the cognitive microstructure of event-based prospective memory.  相似文献   
866.
Cognitive aspects of chronic depression   总被引:3,自引:0,他引:3  
Previous research on chronic depression has focused on its link with other mood disorders and Axis II personality disorders. However, there are few data examining whether the cognitive perspective applies to this condition. In this cross-sectional study, 42 outpatients with chronic depression were compared with 27 outpatients with nonchronic major depressive disorder and 24 never psychiatrically ill controls on cognitive variables thought to be related to vulnerability to depression (e.g., dysfunctional attitudes, attributional style, a ruminative response style, and maladaptive core beliefs). Both depressed groups were more elevated than a never-ill comparison group. However, chronically depressed individuals were generally more elevated on measures of cognitive variables than those with major depressive disorders even after controlling for mood state and personality disorder symptoms.  相似文献   
867.
The experiences of older care recipients have received far less theoretical and empirical attention than those of their family caregivers. In this study of 91 care recipients, the authors assessed perceptions of the amount, timing, and manner of spousal assistance; the amount of strain experienced from receiving care; and psychological well-being. Although female care recipients were more likely to report dissatisfaction with the manner in which assistance was provided, there were few gender differences in perceptions of care overall. In a stringent test of the hypothesis that perceived quality of spousal care affects recipient well-being, the authors found that poorer quality of care was related to increased depressive symptoms and a decreased sense of mastery 1 year later. These longitudinal effects were independent of the recipient's physical disability, marital quality, and care-receiving strain as well as the caregiver's well-being. These findings argue for a comprehensive assessment of the care-receiving experience that includes both care-recipient and caregiver perspectives.  相似文献   
868.
This paper critically examines the biology of species identity and the morality of crossing species boundaries in the context of emerging research that involves combining human and nonhuman animals at the genetic or cellular level. We begin with the notion of species identity, particularly focusing on the ostensible fixity of species boundaries, and we explore the general biological and philosophical problem of defining species. Against this backdrop, we survey and criticize earlier attempts to forbid crossing species boundaries in the creation of novel beings. We do not attempt to establish the immorality of crossing species boundaries, but we conclude with some thoughts about such crossings, alluding to the notion of moral confusion regarding social and ethical obligations to novel interspecies beings.  相似文献   
869.
The two experiments reported examine the role of temporal contiguity on judgments of contingency in a human analogue of the Pavlovian task. The data show that the effect of the actual delay on contingency judgment depends on the observer’s expectation regarding the delay. for a fixed contingency between the cue and the outcome, ratings of the contingency are higher when the actual delay is congruent with the observer’s expectation than when it is incongruent. We argue that our data can be understood within the context of the temporal coding hypothesis.  相似文献   
870.
The purpose of this study was to evaluate the immediate and subsequent effects of fixed-time (FT) food presentations on mouthing. The effects of FT food presentations were analyzed within a three-component multiple schedule in which baseline conditions were implemented during the first and third components and treatment conditions were implemented during the second component. Results indicated that FT food reduced mouthing and that levels of mouthing during post-FT components were reliably lower than pre-FT components. Behavioral mechanisms responsible for treatment effects are discussed.  相似文献   
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