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991.
Four experiments explored how readers use temporal information to construct and update situation models and retrieve them from memory. In Experiment 1, readers spontaneously constructed temporal and spatial situation models of single sentences. In Experiment 2, temporal inconsistencies caused problems in updating situation models similar to those observed previously for other dimensions of situation models. In Experiment 3, merely implied temporal order information was inferred from narratives, affecting comprehension of later sentences like explicitly stated order information. Moreover, inconsistent temporal order information prevented the creation and storage in memory of an integrated situation model. In Experiment 4, a temporal inconsistency increased processing time even if readers were unable to report the inconsistency. These results confirm the significance of the temporal dimension of situation models.  相似文献   
992.
Novice (Experiment 1) and experienced (Experiment 2) young, middle-aged, and older adults learned a new word-processing application in keystrokes, menus, or menus-plus-icons interface conditions. Novices showed strong age differences in the time to complete the 3-day tutorial and in declarative and procedural tests of word-processing knowledge. Menus and menus-plus-icons were superior to keystrokes condition. though interface did not interact with age. Experienced users showed age-related slowing in learning rate but minimal age differences in test performance when retrained on a new word-processing program. Age and computer experience accounted for much of the variance in both learning time and word-processing performance; interface type, speed of processing, and spatial generation ability made additional contributions. Experience interacted with age to predict performance. Implications for training and retraining older workers are discussed.  相似文献   
993.
Heritable influences on cognitive functioning were investigated in a sample of 403 pairs of like-sex Danish twins aged 75 years and older. Twins completed the Mini-Mental State Examination and 3 other cognitive tests. Genetic factors accounted for 26-54% of the variance on these measures, with the balance being due to environmental factors that create differences rather than similarities among reared-together relatives. Deleting twins with severe cognitive impairment had little effect on the results, indicating that the heritability of cognitive functioning was not due entirely to genes affecting dementia. Neither age nor gender moderated twin similarity, and differential social contact could not account for correlation differences between monozygotic and dizygotic twins. These results replicate G. E. McClearn et al.'s (1997) study in indicating substantial genetic influences on late-life cognitive functioning.  相似文献   
994.
The authors investigate two competing hypotheses about how chronic vividness of imagery interacts with the vividness and salience of information in decision making. Results from four studies, covering a variety of decision domains, indicate that chronic imagery vividness rarely amplifies the effects of vivid and salient information. Imagery vividness may, in fact, attenuate the effects of vivid and salient information. This is because, relative to nonvivid imagers, vivid imagers rely less on information that appears obvious and rely more on information that seems less obvious. This tendency is so robust that vividness of imagery may amplify the effects of vivid information only when this information is the only information available in the decision field. The findings seem to reflect vivid imagers' tendency to totally immerse themselves in a decision problem and scrutinize the available information creatively.  相似文献   
995.
Our current understanding into the role of stress in unexplained recurrent miscarriages comes from two different research strategies. The majority of research has examined the role of psychological support within this patient population. This support has been provided in a number of ways ranging from weekly interviews with a psychiatrist or gynaecologist and or visual re-assurance in the form of ultrasound scans. A comparison of psychological support with an absence of such intervention has found differences in successful pregnancy outcome varying from as great as 84 versus 26%, respectively. It has been assumed that psychological support reduces the miscarriage rate by reducing “stress”within this patient population. In addition it provides indirect support for a role of stress in the aetiology of unexplained recurrent miscarriage. Other studies have attempted to directly assess the effect of personality characteristics on miscarriage rate; these studies have yielded conflicting results.The mechanism by which stress may be causal in the aetiology of unexplained recurrent miscarriage has not been examined in humans. Animal studies, however, have found that psychological distress can alter immune parameters that may be intricately involved with implantation. These parameters include an elevation of the “abortive” cytokine TNF-a and a reduction in the “anti-abortive” cytokine TGF-P2. Cells that are involved in the release of TNF-a at the feto-maternal interface include T cells, macrophages and mast cells.Mechanisms through which stress may act on these cells are explored and an integrated model is postulated.  相似文献   
996.
Field T  Diego M  Sanders C 《Adolescence》2001,36(143):491-498
Seventy-nine high school seniors were administered the Center for Epidemiological Studies Depression Scale (CES-D), as well as a questionnaire on parent relationships, peer relationships, positive and negative feelings including suicidal thoughts, and lifestyle variables including academic performance, exercise, and drug use. The group of adolescents who scored above the clinical cutoff for depression on the CES-D (n = 29) had poorer relations with parents. Further, the incidence of paternal depression in that group was greater. The depressed adolescents also had less optimal peer relationships, fewer friends, and were less popular. They experienced less happiness and more frequent suicidal thoughts. They spent less time doing homework, had a lower grade point average, and spent less time exercising. The depressed group also reported more use of marijuana and cocaine. A stepwise regression indicated that physical affection with parents, homework, well-being, exercise, happiness, and parent relations explained 55% of the variance.  相似文献   
997.
The present research examines the role of optimism on time preferences for both losses and gains. It is argued that optimism has asymmetric effects on time preferences for gains versus losses: one reason why decision makers prefer immediate gains is because they are optimistic that these gains will be followed by additional gains in future. In contrast, decision makers prefer to delay losses because they are optimistic that losses are avoidable in the future. Optimism about outcomes affects time preferences for both gains and losses, such that low optimism reduces the discount rates while increased optimism is associated with higher discount rates. This prediction was supported in two different domains: monetary outcomes (Study 1), and health (Study 2). Implications of these results for both research practice and time preferences in the real world are discussed.  相似文献   
998.
This article illustrates how creativity is constituted by forces beyond the innovating individual, drawing examples from the career of the eminent chemist Linus Pauling. From a systems perspective, a scientific theory or other product is creative only if the innovation gains the acceptance of a field of experts and so transforms the culture. In addition to this crucial selective function vis-à-vis the completed work, the social field can play a catalytic role, fostering productive interactions between person and domain throughout a career. Pauling's case yields examples of how variously the social field contributes to creativity, shaping the individual's standards of judgment and providing opportunities, incentives, and critical evaluation. A formidable set of strengths suited Pauling for his scientific achievements, but examination of his career qualifies the notion of a lone genius whose brilliance carries the day.  相似文献   
999.
Rorschach protocols from children and adolescents with Asperger's disorder   总被引:2,自引:0,他引:2  
Rorschach protocols from 24 boys with Asperger's Disorder matched by age to 24 boys with other emotional or behavioral disorders (the contrast group) were compared to each other and to Exner' s (1995) normative data. Eight variables based on Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) criteria and a review of the literature for Asperger's Disorder were predicted to discriminate between groups with the Asperger's group having more extreme scores. Five variables (COP, CDI, H, M, and EA) were significantly different from the contrast group and T and WSumC were significantly different from the normative data in both the Asperger's group and the contrast group.  相似文献   
1000.
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