120 resultados para Cognition distribuée
Resumo:
The apolipoprotein (APOE) epsilon4 allele is a genetic risk factor for the development of Alzheimer's disease (AD). It has also been associated with vascular dementia (VaD) in some but not all studies. Previous studies have examined the role of APOE in predicting performance on cognitive tests in both demented and non-demented populations. In cognitively intact individuals, statistically significant group differences between APOE epsilon4 carriers and non-carriers have been demonstrated for several cognitive domains. In AD studies of the impact of APOE epsilon4 on cognition have been conflicting while no previous study has assessed cognition and impact of APOE epsilon4 in VaD. In this study we investigated the impact of APOE epsilon4 on performance in neuropsychological tests including information processing speed in patients with mild-moderate AD and VaD. We incorporated both computerized and pen and paper tests to ensure a sensitive method of assessing cognition. 109 patients participated in the study (VaD=41, AD=68). Neurocognitive performance of 44 epsilon4 present AD patients was compared to 24 epsilon4absent patients and performance of 23 epsilon4 present VaD patients was compared to 18 epsilon4 absent patients. There was evidence that APOE epsilon4 conferred a risk of poorer cognitive functioning in both patient groups. In the AD group presence of epsilon4 conferred a negative impact on some measures of speed of information processing and immediate recall while in the VaD group epsilon4 present patients had evidence of poorer accuracy on tasks such as choice reaction time and spatial working memory. In AD and VaD groups epsilon4 present patients showed impairment in selective attention. These findings provide further support of the negative impact of the epsilon4 allele in cognition.
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alpha 1-antichymotrypsin (AACT) is a serine protease inhibitor that has been associated with amyloid plaques in the brains of patients with Alzheimer's disease (AD). It has been reported that AACT serum levels are higher in AD patients than in age and sex matched controls. In addition, polymorphisms in the signal peptide and 5' of the AACT gene have been reported to increase the risk of developing AD, Serum AACT has also been suggested to be associated with cognitive decline in elderly subjects. Our objective was to investigate whether a relationship existed between serum AACT levels, AACT genotypes and risk for AD in a case control association study using 108 clinically well defined late onset AD cases and 108 age and sex matched controls from Northern Ireland. We also wished to determine whether higher serum AACT affected levels of cognition as had been previously reported. Serum AACT levels were found to bet significantly raised in cases compared to controls (t = 3.8, df = 209, p
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Relevance theory (Sperber & Wilson. 1995) suggests that people expend cognitive effort when processing information in proportion to the cognitive effects to be gained from doing so. This theory has been used to explain how people apply their knowledge appropriately when evaluating category-based inductive arguments (Medin, Coley, Storms, & Hayes, 2003). In such arguments, people are told that a property is true of premise categories and are asked to evaluate the likelihood that it is also true of conclusion categories. According to the relevance framework, reasoners generate hypotheses about the relevant relation between the categories in the argument. We reasoned that premises inconsistent with early hypotheses about the relevant relation would have greater effects than consistent premises. We designed three premise garden-path arguments where the same 3rd premise was either consistent or inconsistent with likely hypotheses about the relevant relation. In Experiments 1 and 2, we showed that effort expended processing consistent premises (measured via reading times) was significantly less than effort expended on inconsistent premises. In Experiment 2 and 3, we demonstrated a direct relation between cognitive effect and cognitive effort. For garden-path arguments, belief change given inconsistent 3rd premises was significantly correlated with Premise 3 (Experiment 3) and conclusion (Experiments 2 and 3) reading times. For consistent arguments, the correlation between belief change and reading times did not approach significance. These results support the relevance framework for induction but are difficult to accommodate under other approaches.
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In this article, we discuss the range of concerns people weigh when evaluating the acceptability of harmful actions and propose a new perspective on the relationship between harm and morality. With this aim, we examine Kelly, Stich, Haley, Eng and Fessler’s (2007) recent claim that, contrary to Turiel and associates, people do not judge harm to be authority independent and general in scope in the context of complex harmful scenarios (e.g., prisoner interrogation, military training). In a modified replication of their study, we examined participants’ judgments of harmful actions in these contexts by taking into account their explanations for their judgments. We claim that both in terms of participants’ judgments and rationales, the results largely confirm our hypothesis that actions involving harm and injustice or rights violation are judged to be authority independent and general in scope, which is a modification of Turiel’s traditional hypothesis.
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Many theoretical claims about the folk concept of moral responsibility coming from the current literature are indeterminate because researchers do not clearly specify the folk concept of moral responsibility in question. The article pursues a cognitive approach to folk concepts that pays special attention to this indeterminacy problem. After addressing the problem, the article provides evidence on folk attributions of moral responsibility in the case a failed attempt to kill that goes against a specific claim coming from the current literature—that the dimension of causation is part of the structure of the folk concept of moral responsibility.
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Objective
To examine the extent to which the illness perceptions of Oesophageal cancer survivors and the illness perceptions of their carers explain the survivors' levels of psychological distress (in terms of anxiety and depression symptoms) relative to demographic and biomedical variables and patients' coping strategies.
Method
Everyone registered with the Oesophageal Patients' Association in the UK was mailed a questionnaire booklet containing questions about medical and demographic variables, the Illness Perception Questionnaire-Revised, the Cancer Coping Questionnaire, and the Hospital Anxiety and Depression Scale. Patients were asked to pass a modified version of the Illness Perception Questionnaire-Revised to someone they identified as a carer. Complete responses were received from 317 dyads.
Results
Regression models indicated that the variables measured could explain 56% of the variance in anxiety and 54% of the variance in depression. Patients' illness perceptions explained the majority of this variance. Positive focus coping strategies were also found to be important in explaining psychological well-being. Some of the carers' illness perceptions made a significant contribution to the explanation of the patients' levels of psychological distress, and in some instances, carer perceptions were found to moderate the relationship between patients' perceptions and psychological distress.
Conclusion
The findings suggest that cognition-based interventions could potentially be most effective in minimizing emotional distress among survivors of Oesophageal cancer. This study also shows that these interventions could usefully be delivered at the level of the patient–carer dyad.
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Background: This is an update of a Cochrane review first published in 2001. At that stage there was insufficient evidence to recommend statins for the prevention of Alzheimer's disease (AD). The scope of this review has been expanded to include all forms of dementia.
Objectives: To assess the effects of statins in the prevention of dementia.
Search strategy: The Specialized Register of the Cochrane Dementia and Cognitive Improvement Group, The Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL and LILACS were searched on 10 October 2007 using the terms statin*, lovastatin*, pravastatin*, simvastatin*, fluvastatin*, atorvastatin* and rosuvastatin*. The CDCIG Register contains records from many healthcare databases, SIGLE, LILACS as well as many trials databases and is updated regularly.
Selection criteria: Double-blind randomized placebo-controlled trials of statins in people at risk of AD and dementia.
Data collection and analysis: Two independent reviewers extracted and assessed data independently and agreement was reached after discussion. Adverse effects were noted.
Main results: Two trials were identified with 26,340 participants; HPS 2002 and PROSPER 2002. Age range was 40-82 years across the two studies, PROSPER 2002 included 5804 patients aged 70-82 years and HPS included 20,536 patients with 5806 at least 70 years old at study entry. Mean total cholesterol 5.9 mmol/l, LDL cholesterol 3.4 mmol/l at study entry with mean reduction in LDL cholesterol of 1.0mmol/l in simvastatin treated patients compared to placebo in HPS 2002. Mean total cholesterol 5.7 mmol/l, LDL cholesterol 3.8 mmol/l at study entry with mean reduction in LDL cholesterol of 1.02 mmol/l in pravastatin treated patients compared to placebo in PROSPER 2002. Mean follow-up 3.2 years in PROSPER, 5 years in HPS 2002. Cognition was measured at different times and with different scales so could not be combined in a meta-analysis. There was no difference in incidence of dementia in HPS 2002 (31 cases in simvastatin group, 31 cases in placebo group) nor in performance on the modified Telephone Interview for Cognitive Status at final follow-up (23.7% simvastatin group cognitively impaired vs 24.2% in placebo group). There was no difference in cognition between groups either in relation to age at study entry or previous history of cerebrovascular disease. Cognitive function declined at the same rate in both treatment groups in PROSPER 2002, there was no significant difference between pravastatin treated and placebo groups in performance on letter digit codes, picture word learning test, Stroop and Mini Mental State Examination. There was no evidence that statins were detrimental to cognition.
Authors' conclusions : There is good evidence from RCTs that statins given in late life to individuals at risk of vascular disease have no effect in preventing AD or dementia. Biologically it seems feasible that statins could prevent dementia due to their role in cholesterol reduction and initial evidence from observational studies was very promising. Indication bias may have been a factor in these studies however and the evidence from subsequent RCTs has been negative.
Resumo:
Objective: The research aimed to determine the extent to which illness cognitions and coping explain psychological distress (fear of cancer recurrence, anxiety and depression symptoms) among family carers of survivors of oesophageal cancer.
Methods: Carers of patients registered with the Oesophageal Patients' Association in the UK were mailed a questionnaire booklet containing questions about medical and demographic variables, the Illness Perception Questionnaire-Revised, the Cancer Coping Questionnaire, the Concerns about Recurrence Scale and the Hospital Anxiety and Depression Scale.
Results: Complete responses were received from 382 family carers (75% male; mean (SD) age=62 (10.91) years). Regression models indicated that the variables measured could explain between 35 and 49% of the variance in psychological distress among carers. Illness cognitions (particularly perceptions of the cause of, consequences of and personal control over oesophageal cancer and the carer's understanding of the condition) explained the majority of this variance. Positive focus coping strategies were also found to be important in explaining psychological distress.
Conclusion: The results of this study are consistent with previous research demonstrating that illness cognitions are significant correlates of adaptive outcomes, thereby suggesting that cognition-based interventions could potentially be effective in minimizing emotional distress among family carers of oesophageal cancer survivors.
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Leventhal's common sense model has provided a useful framework for explaining psychological distress in several chronic illnesses. The model indicates that a person's perception of their illness and their coping strategies are the key determinants of their experience of psychological distress. The present research examines whether illness perceptions and coping strategies are related to levels of psychological distress among survivors of esophageal cancer. Everyone registered with the Oesophageal Patients' Association in the UK was mailed a questionnaire booklet, which included the Illness Perception Questionnaire-Revised, the Cancer Coping Questionnaire, and the Hospital Anxiety and Depression Scale. Complete responses were received from 484 people. Regression models indicated that the variables measured could explain 51% of the variance in anxiety and 42% of the variance in depression. Perceptions of esophageal cancer explained the majority of this variance. Positive focus coping strategies were also found to be important in explaining psychological distress. The results of this study are consistent with previous research demonstrating that illness perceptions are stronger correlates of adaptive outcomes than coping strategies. The findings suggest that cognition-based interventions could potentially be most effective in minimizing emotional distress among survivors of esophageal cancer.
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The capacity to attribute beliefs to others in order to understand action is one of the mainstays of human cognition. Yet it is debatable whether children attribute beliefs in the same way to all agents. In this paper, we present the results of a false-belief task concerning humans and God run with a sample of Maya children aged 4–7, and place them in the context of several psychological theories of cognitive development. Children were found to attribute beliefs in different ways to humans and God. The evidence also speaks to the debate concerning the universality and uniformity of the development of folk-psychological reasoning.
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Experimental results in reference to Brazilian children and adults are presented in the context of current discussions about essentialism and folkbiology. Using an adoption paradigm, we replicate the basic findings of a previous article in this journal concerning the early emergence in children of a birth-parent bias (Atran et al. 2001). This cognitive bias supports the claim that causal essentialism cross-culturally constrains the reasoning about the origin, development and maintenance of the characteristics and identity of living kinds. We also report some intriguing differences with earlier findings that speak to theoretical and methodological issues of cultural relativity.