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951.
The Category Test (CT) is a neuropsychological measure that taps into multiple domains of complex reasoning but yields a single error score, limiting the use of the test. In this study, three new CT scales were developed to assess specific aspects of executive dysfunction: Perseveration, Failure to Maintain Cognitive Set, and Inability to Recall and Re-Initiate Past Behavior. The relationship of these scales to well-established neuropsychological measures was examined in head-injured individuals and schizophrenia patients. The CT Perseveration score was correlated with the Wisconsin Card Sorting Test (WCST) Perseverative Responses score, but also with measures from the Wechsler Memory Scale-Revised and the California Verbal Learning Test. The CT Memory score correlated with other memory measures, but also with the WCST Perseveration measure. Although future studies designed to test discriminant and convergent validity are warranted, these scales may be useful in determining specific aspects of impaired CT performance.  相似文献   
952.
Involvement of BDNF receptor TrkB in spatial memory formation   总被引:11,自引:0,他引:11       下载免费PDF全文
The N-methyl-D-aspartate (NMDA) receptors are involved in long-term potentiation (LTP), and are phosphorylated by several tyrosine kinases including a Src-family tyrosine kinase Fyn. Brain-derived neurotrophic factor (BDNF) is a neurotrophin, which also enhances hippocampal synaptic transmission and efficacy by increasing NMDA receptor activity. Here, we show that Fyn is a key molecule linking the BDNF receptor TrkB with NMDA receptors, which play an important role in spatial memory formation in a radial arm maze. Spatial learning induced phosphorylation of TrkB, Fyn, and NR2B, but not NR2A, in the hippocampus. Fyn was coimmunoprecipitated with TrkB and NR2B, and this association was increased in well-trained rats compared with control animals. Continuous intracerebroventricular infusion of PP2, a tyrosine kinase inhibitor, in rats delayed memory acquisition in the radial arm maze, but PP2-treated animals reached the same level of learning as the controls. The phosphorylation of Fyn and NR2B, but not TrkB, was diminished by PP2 treatment. Our findings suggest the importance of interaction between BDNF/TrkB signaling and NMDA receptors for spatial memory in the hippocampus.  相似文献   
953.
Evered L  Ruff R  Baldo J  Isomura A 《Assessment》2003,10(4):420-427
Emotional risk factors were examined in 129 litigant and nonlitigant patients diagnosed with Postconcussional Disorder (PCD) following Mild Traumatic Brain Injury (MTBI). According to Millon Clinical Multiaxial Inventory (MCMI) criteria, four subgroups emerged: (a) 14.7% met criteria for an Axis I disorder, (b) 24.8% for an Axis II disorder, (c) 24.0% for bout Axis I and II disorders, and (d) 36.4% fell below threshold for psychopathology. Thus, 63.5% endorsed emotional pathology. Of the four groups, those with both Axis I and II psychopathology presented the greatest number of emotional complaints in a clinical interview and manifested the lowest neurocognitive test scores. Motor skills, verbal abilities, memory functioning, and IQ were primarily affected. With the exception of post-morbid emotional complaints, no significant differences were identified between litigants and nonlitigants. Our analysis suggests that the combination of both Axis I and II psychopathology is associated with greater impairment following MTBI.  相似文献   
954.
When people use a computer application, they have the opportunity to adapt the methods or strategies that they deploy to better fit the demands of the task. In Experiment 1, we demonstrated that the generation of methods is limited by, but not entirely prevented by, the reduced opportunity that is associated with the iterative nature of typical computer-based tasks. In Experiment 2, we demonstrated that the cognitive demands associated with task-related problem solving delay, but do not prevent, the generation of more efficient device strategies. We argue that people are rather good at adapting device strategies to task demands and that previously reported arguments to the contrary are premature.  相似文献   
955.
Social psychologists have shown a profound interest in intergroup relationships, but there are very few papers focusing on the developmental aspects that explain the psychological mechanisms involved in the construction of group and cultural identity. Our research aims to explore how the self-categorization of Andalusian children evolves. We tried to assess the degree to which they self-identify as Andalusian, Spanish, and European, and how this identification changes with age. We were also interested in the affective evaluation of different groups (French, Italian, English, German, Spanish, Catalonian, and Andalusian) made by Andalusian children. Furthermore, we analyzed the relationship between self-categorization and the evaluation of these groups. Results show that the development of national (autonomous community) identity in these children is influenced by their cognitive development, as well as by the relationships among the regional communities of Spain and the relationships between Spain and other countries. The peculiarity of Andalusians as a group is that they assume both identities: Spanish and Andalusian, from a very early age. In-group favoritism is an extended phenomenon at all ages, and Andalusian children have a negative stereotype of the other Spanish groups and other European communities.  相似文献   
956.
Previous research has revealed a persistent association between social structure and mental health. However, most researchers have focused only on the psychological and psychosocial aspects of that relationship. The present paper indicates the need to include the social and structural bases of distress in our theoretical models. Starting from a general social and psychological model, our research considered the role of several social, environmental, and structural variables (social position, social stressors, and social integration), psychological factors (self-esteem), and psychosocial variables (perceived social support). The theoretical model was tested working with a group of Spanish participants (N = 401) that covered a range of social positions. The results obtained using structural equation modeling support our model, showing the relevant role played by psychosocial, psychological and social, and structural factors. Implications for theory and intervention are discussed.  相似文献   
957.
The objective was to investigate intentional and unintentional nonadherence to anti-HIV treatment regimens from a decision-making perspective. The participants (n?=?117) being treated with anti-HIV medication completed a questionnaire asking about nonadherence; reasons for and against taking the medication; and medical consultation style. Thirty-three participants (29%) reported intentionally missing or altering doses of medication at least 5% of the time; 59 participants (50%) reported forgetting to take medication at least 5% of the time. Intentional nonadherence was associated with the balance of the perceived benefits and losses of taking medication, and extent to which participants were 'prepared for the effects of the medication'. Unintentional nonadherence was associated with demographic and clinical variables. The research highlights the importance of (i) treating intentional and unintentional nonadherence as separate entities; (ii) assessing individuals' idiosyncratic beliefs and internal logic when considering intentional nonadherence; and (iii) ensuring that individuals feel prepared for the effects of their medications.  相似文献   
958.
The aim of the present study was to investigate whether coping resources mediated the changes in Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) specific salivary antibodies caused by academic stress. Fifty-four first-year female students of nursing and physiotherapy completed pencil and paper written questionnaires and concurrently donated saliva samples. The instrument included the short version of the Sense of Coherence (SOC) scale, measures of social support, current health, health practices, the scale of psychological distress, and state anxiety questionnaire. Data and saliva samples were collected one month after the beginning of the first semester, during term examinations period and a month into the second semester. Statistically significant changes in the level of specific salivary EBV and HCMV antibodies were observed between the four study points. State anxiety and psychological distress were significantly associated with HCMV-specific salivary antibody level increase during examinations and its decrease after the stress was over. Coping resources, however, were not associated with changes in any of the antibodies studied.  相似文献   
959.
The accuracy of perceptions about self-harm that are presented in the psychological and psychiatric literature was assessed with a sample of self-harmers. A list of 20 statements containing ten myths and ten accurate statements about self-harm behaviour was incorporated into an internet-based questionnaire. Respondents (n?=?243) rated their extent of agreement with each statement. Factor analysis confirmed the a priori classification of statements as being accurate. Only one item, regarding the relationship of self-harm to previous sexual abuse, did not confirm a priori classification; this statement was considered by self-harmers to be an accurate perception of self-harm. It was concluded that this questionnaire could be a useful aid for group-work training with professionals who are involved in working with people who engage in self-harm.  相似文献   
960.
Joint attention to an external object at the end of the first year is typically believed to herald the infant's discovery of other people's attention. I will argue that mutual attention in the first months of life already involves an awareness of the directedness of attention. The self is experienced as the first object of this directedness followed by gradually more distal 'objects'. This view explains early infant affective self-consciousness within mutual attention as emotionally meaningful, rather than as bearing only a spurious similarity to that in the second and third years of life. Such engagements precede and must inform, rather than derive from, conceptual representations of self and other, and can be better described as self-other conscious affects.  相似文献   
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