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961.
The debate continues with regard to whether degradation of semantic knowledge or deficits in information processing lead to impaired memory performance in patients with Alzheimer's disease (AD). This study examined the effects of semantic content and working memory demands on the recall and recognition abilities of patients with mild AD. Nineteen patients with probable AD and 19 demographically matched normal control participants were asked to remember prose passages that varied in semantic content (high, medium, and low level of idea importance) and working memory demands (narrative and expository passages). Compared to the controls, patients with mild AD lost the ability to recall prose in a manner consistent with the semantic structure of the passages as the demands on working memory increased. Furthermore, as the demands on working memory increased, patients recognized information in a manner that suggested their initial processing was of isolated details rather than by semantic structure. This study provides support for the hypothesis that information processing deficits contribute to impaired semantic processing in patients with mild AD.  相似文献   
962.
This paper reviews research from the longitudinal Einstein Aging Studies (EAS) that has focused on modeling intraindividual cognitive change in aging adults. We describe how to separate models of intraindividual change at the within-person level from models of individual differences in change at the between-person level. We illustrate this distinction by analyzing new data from the EAS to test the speed hypothesis at the intraindividual level of analyses. The present findings replicate those of Sliwinski and Buschke (1999) by showing that within-person changes in speed predict within-person changes in cognition, but that speed does not substantially attenuate estimates of within-person cognitive decline. We conclude that correct measurement and explanatory modeling of intraindividual change should be the primary focus of longitudinal aging research, and that the more common practice of modeling individual differences in change should be a secondary focus.  相似文献   
963.
This paper summarizes and expands research on cognitive aging from the Berlin Aging Study (BASE), a longitudinal, multidisciplinary, and population-based investigation of old and very old individuals. First, we describe previously reported research on five key themes: (a) experimental and mortality-associated components of longitudinal selectivity; (b) comparisons between cross-sectional and cross-sectional/longitudinal convergence age gradients; (c) old-age dedifferentiation of inter-individual differences; (d) possible reasons for the age-based increase in the link between intellectual and sensory domains; and (e) limits to cognitive plasticity in very old age. Second, we make use of multilevel modeling to determine the magnitude and direction of retest effects. Retest effects are classified as either flat (step function from the first to the second measurement occasion) or growing (linear increase after the first measurement occasion). Five of the eight longitudinally administered cognitive tests are found to display significant retest effects of either or both types. Retest adjustment increased the linear negative and decreased the quadratic negative component of cross-sectional/longitudinal convergence gradients in measures of intellectual abilities.  相似文献   
964.
Feedback-based learning declines with age. Because older adults are generally biased toward positive information (“positivity effect”), learning from positive feedback may be less impaired than learning from negative outcomes. The literature documents mixed results, due possibly to variability between studies in task design. In the current series of studies, we investigated the influence of feedback valence on reinforcement learning in young and older adults. We used nonprobabilistic learning tasks, to more systematically study the effects of feedback magnitude, learning of stimulus–response (S–R) versus stimulus–outcome (S–O) associations, and working-memory capacity. In most experiments, older adults benefitted more from positive than negative feedback, but only with large feedback magnitudes. Positivity effects were pronounced for S–O learning, whereas S–R learning correlated with working-memory capacity in both age groups. These results underline the context dependence of positivity effects in learning and suggest that older adults focus on high gains when these are informative for behavior.  相似文献   
965.
966.
ABSTRACT

Objective: To examine whether emotional memory (EM) of objects with self-reference in Alzheimer's disease (AD) can be modeled with binomial logistic regression in a free recall and an object recognition test to predict EM enhancement.?Method: Twenty patients with AD and twenty healthy controls were studied. Six objects (three presented as gifts) were shown to each participant. Ten minutes later, a free recall and a recognition test were applied. The recognition test had target–objects mixed with six similar distracter objects. Participants were asked to name any object in the recall test and identify each object in the recognition test as known or unknown.?Results: The total of gift objects recalled in AD patients (41.6%) was larger than neutral objects (13.3%) and a significant EM recall effect for gifts was found (Wilcoxon: p < .003). EM was not found for recognition in AD patients due to a ceiling effect. Healthy older adults scored overall higher in recall and recognition but showed no EM enhancement due to a ceiling effect. A logistic regression showed that likelihood of emotional recall memory can be modeled as a function of MMSE score (p < .014) and object status (p < .0001) as gift or non-gift.?Conclusion: Recall memory was enhanced in AD patients for emotional objects indicating that EM in mild to moderate AD although impaired can be provoked with strong emotional load. The logistic regression model suggests that EM declines with the progression of AD rather than disrupts and may be a useful tool for evaluating magnitude of emotional load.  相似文献   
967.
There are two distinct views on how to formulate an objective consequentialist account of the deontic status of actions, actualism and possibilism. On an actualist account, what matters to the deontic status of actions is only the value of the outcome an action would have, if performed. By contrast, a possibilist account also takes into account the value of the outcomes that an action could have. These two views come apart in their deontic verdicts when an agent is imperfect in an avoidable way, viz., when agent brings about less good than she could. In this paper, I offer an argument against actualism that draws on the connection between moral obligation and practical reasons.  相似文献   
968.
Conducted within the Canadian Forces (N=652), this study explores the role of self-determined motivation and affective commitment in relation to personnel retention within the military. Three groupings of variables are used in order to shed light on the mechanisms underlying personnel retention: a) distal antecedents (i.e. leadership styles), b) proximal antecedents (i.e. group cohesion and work climate) and c) mediators (i.e. self-determined motivation and affective commitment). Illustrated through a structural model, results demonstrate the existence of a partial mediator effect from affective commitment in the relationship between self-determined motivation and intention to stay. These findings are discussed in regards of their implications from theoretical and practical perspectives.  相似文献   
969.
Sexual abuse of adolescents can have detrimental effects on their perceptions of their different future life-roles. We investigated such perceptions of students with a history of sexual abuse (n=163) as well as typically developing others (n=237). Participants completed the Life-role Inventory of the then called Human Sciences Research Council (Langley, 1990). Between-group comparisons were carried out. Adolescents with a history of sexual abuse reported negative perceptions of themselves fulfilling some of their roles in the future, being committed to these roles and attaching value to them, compared to typically developing others.  相似文献   
970.
This study piloted the efficacy of a short-term intervention program for socio-emotional development in pre-schoolers.in a South African setting. Participants were 48 learners, aged between 5 and 6 years (22 boys, 26 girls). A proportion of the participants (n=26) took the socio-emotional competence development intervention. Programme effects were measured using the Social Competence and Behavioural Evaluation, Preschool Edition (SCBE) and the Griffiths Developmental Scales—Extended Revised (GMDS-ER). Between group comparisons showed significant gains in internalization and social competence skills in favour of the intervention group as compared to the control group.  相似文献   
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